# Endangered and Threatened Wildlife and Plants; Determination of Threatened Species Status for the Georgetown Salamander and Salado Salamander Throughout Their Ranges

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/fr%3A2014-03717

## Record

- **Collection:** Federal Register
- **Document type:** Rule
- **Published:** February 24, 2014
- **Citation:** 79 FR 10236

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R2-ES-2012-0035; 4500030113]
RIN 1018-AY22
Endangered and Threatened Wildlife and Plants; Determination of Threatened Species Status for the Georgetown Salamander and Salado Salamander Throughout Their Ranges

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Final rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), determine threatened status for the Georgetown salamander (
Eurycea naufragia
) and the Salado salamander (
Eurycea chisholmensis
) under the Endangered Species Act of 1973 (Act), as amended. The effect of this regulation is to conserve the two salamander species and their habitats under the Act. This final rule implements the Federal protections provided by the Act for these species. We are also notifying the public that, in addition to this final listing determination, today we publish a proposed special rule under the Act for the Georgetown salamander.

DATES:

This rule becomes effective March 26, 2014.

ADDRESSES:

This final rule is available on the Internet at
http://www.regulations.gov
and
http://www.fws.gov/southwest/es/AustinTexas
/. Comments and materials received, as well as supporting documentation used in preparing this final rule, are available for public inspection, by appointment, during normal business hours, at U.S. Fish and Wildlife Service, Austin Ecological Services Field Office (see
FOR FURTHER INFORMATION CONTACT
).

FOR FURTHER INFORMATION CONTACT:

Adam Zerrenner, Field Supervisor, U.S. Fish and Wildlife Service, Austin Ecological Services Field Office, 10711 Burnet Rd, Suite 200, Austin, TX 78758; by telephone 512-490-0057; or by facsimile 512-490-0974. Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

Why we need to publish a rule.
Under the Act, a species may warrant protection through listing if it is endangered or threatened throughout all or a significant portion of its range. Listing a species as an endangered or threatened species can only be completed by issuing a rule.

This rule lists the Georgetown and Salado salamanders as threatened species under the Act.

The basis for our action.
Under the Act, we can determine that a species is an endangered or threatened species based on any of five factors: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) Overutilization for commercial, recreational, scientific, or educational purposes; (C) Disease or predation; (D) The inadequacy of existing regulatory mechanisms; or (E) Other natural or manmade factors affecting its continued existence. We have determined that the Georgetown and Salado salamanders are threatened under the Act due to threats faced by the species both now and in the future from Factors A, D, and E.

Peer review and public comment.
We sought comments from independent specialists to ensure that our designation is based on scientifically sound data, assumptions, and analyses. We invited these peer reviewers to comment on our listing proposal. We also considered all comments and information received during the comment period (see Summary of Comments and Recommendations section below).

Background

Previous Federal Action

The Georgetown salamander was included in 10 Candidate Notices of Review:

• 66 FR 54808, October 30, 2001;

• 67 FR 40657, June 13, 2002;

• 69 FR 24876, May 4, 2004;

• 70 FR 24870, May 11, 2005;

• 71 FR 53756, September 12, 2006;

• 72 FR 69034, December 6, 2007;

• 73 FR 75176, December 10, 2008;

• 74 FR 57804, November 9, 2009;

• 75 FR 69222, November 10, 2010; and

• 76 FR 66370, October 26, 2011.

In the 2008 review, the listing priority number was lowered from 2 to 8, indicating that threats to the species were imminent, but moderate to low in magnitude. This reduction in listing priority number was primarily due to the land acquisition and conservation efforts of the Williamson County Conservation Foundation. In addition, we were petitioned by the Center for Biological Diversity to list the Georgetown salamander as an endangered species on May 11, 2004, but at that time, it was already a candidate species whose listing was precluded by higher priority actions.

The Salado salamander was included in nine Candidate Notices of Review:

• 67 FR 40657, June 13, 2002;

• 69 FR 24876, May 4, 2004;

• 70 FR 24870, May 11, 2005;

• 71 FR 53756, September 12, 2006;

• 72 FR 69034, December 6, 2007;

• 73 FR 75176, December 10, 2008;

• 74 FR 57804, November 9, 2009;

• 75 FR 69222, November 10, 2010; and

• 76 FR 66370, October 26, 2011.

The listing priority number has remained at 2 throughout the reviews, indicating that threats to the species were both imminent and high in magnitude. In addition, on May 11, 2004, the Service received a petition from the Center for Biological Diversity to list 225 species we previously had identified as candidates for listing in accordance with section 4 of the Act, including the Salado salamander.

On August 22, 2012, we published a proposed rule to list as endangered and designate critical habitat for the Austin blind salamander (
Eurycea waterlooensis
), Jollyville Plateau salamander (
Eurycea tonkawae
), Georgetown salamander, and Salado salamanders (77 FR 50768). That proposal had a 60-day comment period, ending October 22, 2012. We held a public meeting and hearing in Round Rock, Texas, on September 5, 2012, and a second public meeting and hearing in Austin, Texas, on September 6, 2012. On January 25, 2013, we reopened the public comment period on the August 22, 2012, proposed listing and critical habitat designation; announced the availability of a draft economic analysis; and an amended required determinations section of the proposal (78 FR 5385). On August 20, 2013, we extended the final determination for the Georgetown and Salado salamanders by 6 months due to substantial disagreement regarding: (1) The short- and long-term population trends of these two species; (2) the interpretation of water quality and quantity degradation information as it relates to the status of these two species; and (3) the effectiveness of conservation practices and regulatory mechanisms (78 FR 51129). That comment period closed on September 19, 2013.

Since that time, the City of Georgetown, Texas, prepared and finalized ordinances for the Georgetown salamander. All 17 of the known Georgetown salamander locations are within the City of Georgetown's jurisdiction for residential and commercial development. The enacted

ordinances were directed at alleviating threats to the Georgetown salamander from urban development by requiring geologic assessments prior to construction, establishing occupied site protections through stream buffers, maintaining water quality through best management practices, developing a water quality management plan for the City of Georgetown, and monitoring occupied spring sites by an adaptive management working group. In order to consider the ordinances in our final listing determination, on January 7, 2014 (79 FR 800), we reopened the comment period for 15 days on the proposed listing rule to allow the public an opportunity to provide comment on the application of the City of Georgetown's ordinances to our status determination under section 4(a)(1) of the Act.

This rule constitutes our final determination to list the Georgetown and Salado salamanders as threatened species.

Species Information

Taxonomy

The Georgetown and Salado salamanders are neotenic (do not transform into a terrestrial form) members of the family Plethodontidae. Plethodontid salamanders comprise the largest family of salamanders within the Order Caudata, and are characterized by an absence of lungs (Petranka 1998, pp. 157-158). The Jollyville Plateau (
Eurycea tonkawae
), Georgetown, and Salado salamanders have very similar external morphology. Because of this, they were previously believed to be the same species; however, molecular evidence strongly supports that there is a high level of divergence between the three groups (Chippindale
et al.
2000, pp. 15-16; Chippindale 2010, p. 2).

Morphological Characteristics

As neotenic salamanders, the Georgetown and Salado salamanders retain external feathery gills and inhabit aquatic habitats (springs, spring-runs, wet caves, and groundwater) throughout their lives (Chippindale
et al.
2000, p. 1). In other words, these salamanders are aquatic and respire through gills and permeable skin (Duellman and Trueb 1986, p. 217). Also, adult salamanders of these species are about 2 inches (in) (5 centimeters (cm)) long (Chippindale
et al.
2000, pp. 32-42; Hillis
et al.
2001, p. 268).

Habitat

Both species inhabit water of high quality with a narrow range of conditions (for example, temperature, pH, and alkalinity) maintained by groundwater from various sources. The Georgetown and Salado salamanders depend on high-quality water in sufficient quantity and quality to meet their life-history requirements for survival, growth, and reproduction. Much of this water is sourced from the Northern Segment of the Edwards Aquifer, which is a karst aquifer characterized by open chambers such as caves, fractures, and other cavities that were formed either directly or indirectly by dissolution of subsurface rock formations. Water for the salamanders is provided by infiltration of surface water through the soil or recharge features (caves, faults, fractures, sinkholes, or other open cavities) into the Edwards Aquifer, which discharges from springs as groundwater (Schram 1995, p. 91).

The Georgetown and Salado salamanders spend varying portions of their life within their surface habitats (the wetted top layer of substrate in or near spring openings and pools as well as spring runs) and subsurface habitats (within caves or other underground areas of the underlying groundwater source). Although surface and subsurface habitats are often discussed separately within this final rule, it is important to note the interconnectedness of these areas. Subsurface habitat does not necessarily refer to an expansive cave underground. Rather, it may be described as the water-filled rock matrix below the stream bed. As such, subsurface habitats are impacted by the same threats that impact surface habitat, as the two exist as a continuum (Bendik 2012, City of Austin (COA), pers. comm.).

Salamanders move an unknown depth into interstitial spaces (empty voids between rocks) within the spring or streambed substrate that provide foraging habitat and protection from predators and drought conditions (Cole 1995, p. 24; Pierce and Wall 2011, pp. 16-17). They may also use deeper passages of the aquifer that connect to the spring opening (Dries 2011, COA, pers. comm.). This behavior makes it difficult to accurately estimate population sizes, as only salamanders on the surface can be regularly monitored. However, techniques have been developed for marking individual salamanders, which allows for better estimating population numbers using “mark and recapture” data analysis techniques. These techniques have been used by the COA on the Jollyville Plateau salamander (Bendik
et al.
2013, pp. 2-7) and by Dr. Benjamin Pierce at Southwestern University on the Georgetown salamander (Pierce 2011, pp. 5-7).

Range

The habitats of the Georgetown and Salado salamanders occur in the Northern Segment of the Edwards Aquifer. The recharge and contributing zones of this segment of the Edwards Aquifer are found in portions of Travis, Williamson, and Bell Counties, Texas (Jones 2003, p. 3).

Diet

Although we are unaware of detailed dietary studies for Georgetown and Salado salamanders, their diets are presumed to be similar to other
Eurycea
species, which consist of small aquatic invertebrates such as amphipods, copepods, isopods, and insect larvae (COA 2001, pp. 5-6). A stomach content analysis by the City of Austin demonstrated that the Jollyville Plateau salamander preys on varying proportions of aquatic invertebrates, such as ostracods, copepods, mayfly larvae, fly larvae, snails, water mites, aquatic beetles, and stone fly larvae, depending on the location of the site (Bendik 2011b, pers. comm.). The feces of one wild-caught Austin blind salamander (
Eurycea waterlooensis
) contained amphipods, ostracods, copepods, and plant material (Hillis
et al.
2001, p. 273). Gillespie (2013, pp. 5-9) also found that the diet of the closely related Barton Springs salamanders (
Eurycea sosorum
) consisted primarily of planarians or chironomids (flatworms or nonbiting midge flies), depending on which was more abundant, and amphipods (when planarians and chironomids were rare).

Predation

The Georgetown and Salado salamanders share similar predators, which include centrarchid fish (carnivorous freshwater fish belonging to the sunfish family), crayfish (
Cambarus
sp.), and large aquatic insects (Cole 1995, p. 26; Bowles
et al.
2006, p. 117; Pierce and Wall 2011, pp. 18-20).

Reproduction

The detection of juveniles in all seasons suggests that reproduction occurs year-round (Bendik 2011a, p. 26; Hillis
et al.
2001, p. 273). However, juvenile abundance of Georgetown salamanders typically increases in spring and summer, indicating that there may be relatively more reproduction occurring in winter and early spring compared to other seasons (Pierce 2012, pp. 10-11, 18, 20). In addition, most gravid (egg-bearing) females of the Georgetown salamander are found from October through April (Pierce 2012, p. 8; Pierce and McEntire

2013, p. 6). Because eggs are very rarely found on the surface, these salamanders likely deposit their eggs underground for protection (O'Donnell
et al.
2005, p. 18).

Population Connectivity

More study is needed to determine the nature and extent of the dispersal capabilities of the Georgetown and Salado salamanders. It has been suggested that they may be able to travel some distance through subsurface aquifer conduits. For example, it has been thought that Austin blind salamander can occur underground throughout the entire Barton Springs complex (Dries 2011, COA, pers. comm.). The spring habitats used by salamanders of the Barton Springs complex are not connected on the surface, so the Austin blind salamander population could extend a horizontal distance of at least 984 feet (ft) (300 meters (m)) underground, as this is the approximate distance between the farthest two outlets within the Barton Springs complex known to be occupied by the species. However, a mark-and-recapture study failed to document the movement of endangered Barton Springs salamanders (
Eurycea sosorum
) between any of the springs in the Barton Springs complex (Dries 2012, COA, pers. comm.). This finding could indicate that individual salamanders are not moving the distances between spring openings. Alternatively, this finding could mean that the study simply failed to capture the movement of salamanders. This study has only recently begun and is relatively small in scope.

Due to the similar life history of the Austin blind salamander to the Georgetown and Salado salamanders, it is plausible that populations of these latter two species could also extend 984 ft (300 m) through subterranean habitat, assuming the Austin blind salamander is capable of moving between springs in the Barton Springs complex. However, subsurface movement is likely to be limited by the highly dissected nature of the aquifer system, where spring sites can be separated from other spring sites by large canyons or other physical barriers to movement. Surface movement is similarly inhibited by geologic, hydrologic, physical, and biological barriers (for example, predatory fish commonly found in impoundments along urbanized tributaries (Bendik 2012, COA, pers. comm.). Dye-trace studies have demonstrated that some Jollyville Plateau salamander sites located 2.9 miles (mi) (4.7 kilometers (km)) apart are connected hydrologically (Whitewater Cave to R-Bar-B Spring and Hideaway Cave to R-Bar-B Spring) (Hauwert and Warton 1997, pp. 12-13), but it remains unclear if salamanders are travelling between those sites. Also, in Salado, a large underground conduit that conveys groundwater from the area under the Stagecoach Hotel to Big Boiling Spring is large enough to support salamander movement (Texas Parks and Wildlife Department [TPWD] 2011a, pers. comm.; Mahler 2012, U.S. Geological Survey [USGS], pers. comm.; Yelderman Jr.
et al.
2013, p. 1). In conclusion, some data indicate that some populations could be connected through subterranean water-filled spaces. However, we are unaware of any information available on the frequency of movements and the actual nature of connectivity among populations.

Population Persistence

A population's persistence (ability to survive and avoid extirpation) is influenced by a population's demographic factors (such as survival and reproductive rates) as well as its environment. The population needs of the Georgetown and Salado salamanders are the factors that provide for a high probability of population persistence over the long term at a given site (for example, low degree of threats and high survival and reproduction rates). We are unaware of detailed studies that describe all of the demographic factors that could affect the population persistence of the Georgetown and Salado salamanders; however, we have assessed their probability of persistence by evaluating environmental factors (threats to their surface habitats) and using the available information we know about the number of salamanders that occur at each site.

To estimate the probability of persistence of each population involves considering the predictable responses of the population to various environmental factors (such as the amount of food available or the presence of a toxic substance), as well as the stochasticity. Stochasticity refers to the random, chance, or probabilistic nature of the demographic and environmental processes (Van Dyke 2008, pp. 217-218). Generally, the larger the population, the more likely it is to survive stochastic events in both demographic and environmental factors (Van Dyke 2008, p. 217). Conversely, the smaller the population, the higher its chances are of extirpation when experiencing this demographic and environmental stochasticity.

Rangewide Needs

We used the conservation principles of redundancy, representation, and resiliency (Shaffer and Stein 2000, pp. 307, 309-310) to better inform our view of what contributes to these species' probability of persistence and how best to conserve them. “Resiliency” is the ability of a species to persist through severe hardships or stochastic events (Tear
et al.
2005, p. 841). “Redundancy” means a sufficient number of populations to provide a margin of safety to reduce the risk of losing a species or certain representation (variation) within a species, particularly from catastrophic or other events. “Representation” means conserving “some of everything” with regard to genetic and ecological diversity to allow for future adaptation and maintenance of evolutionary potential. Representation can be measured through the breadth of genetic diversity within and among populations and ecological diversity (also called environmental variation or diversity) occupied by populations across the species range.

A variety of factors contribute to a species' resiliency. These can include how sensitive the species is to disturbances or stressors in its environment, how often they reproduce and how many young they have, how specific or narrow their habitat needs are. A species' resiliency can also be affected by the resiliency of individual populations and the number of populations and their distribution across the landscape. Protecting multiple populations and variation of a species across its range may contribute to its resiliency, especially if some populations or habitats are more susceptible or better adapted to certain threats than others (Service and NOAA 2011, p. 76994). The ability of individuals from populations to disperse and recolonize an area that has been extirpated may also influence their resiliency. As population size and habitat quality increase, the population's ability to persist through periodic hardships also increases.

A minimal level of redundancy is essential for long-term viability (Shaffer and Stein 2000, pp. 307, 309-310; Groves
et al.
2002, p. 506). This provides a margin of safety for a species to withstand catastrophic events (Service and NOAA 2011, p. 76994) by decreasing the chance of any one event affecting the entire species.

Representation and the adaptive capabilities (Service and NOAA 2011, p. 76994) of both the Georgetown and Salado salamanders are also important

for long-term viability. Because a species' genetic makeup is shaped through natural selection by the environments it has experienced (Shaffer and Stein 2000, p. 308), populations should be protected in the array of different environments in which the salamanders occur (surface and subsurface) as a strategy to ensure genetic representation, adaptive capability, and conservation of the species.

To increase the probability of persistence of each species, populations of the Georgetown and Salado salamanders should be conserved in a manner that ensures their variation and representation. This result can be achieved by conserving salamander populations in a diversity of environments (throughout their ranges), including: (1) Both spring and cave locations, (2) habitats with groundwater sources from various aquifers and geologic formations, and (3) at sites with different hydrogeological characteristics, including sites where water flows come from artesian pressure, a perched aquifer, or resurgence through alluvial deposits.

Information for each of the salamander species is discussed in more detail below.

Georgetown Salamander

The Georgetown salamander is characterized by a broad, relatively short head with three pairs of bright-red gills on each side behind the jaws, a rounded and short snout, and large eyes with a gold iris. The upper body is generally grayish with varying patterns of melanophores (cells containing brown or black pigments called melanin) and iridophores (cells filled with iridescent pigments called guanine), while the underside is pale and translucent. The tail tends to be long with poorly developed dorsal and ventral fins that are golden-yellow at the base, cream-colored to translucent toward the outer margin, and mottled with melanophores and iridophores. Unlike the closely related Jollyville Plateau salamander, the Georgetown salamander has a distinct dark border along the lateral margins of the tail fin (Chippindale
et al.
2000, p. 38). As with the Jollyville Plateau salamander, the Georgetown salamander has recently discovered cave-adapted forms with reduced eyes and pale coloration (TPWD 2011, p. 8).

The Georgetown salamander is known from springs along five tributaries (South, Middle, and North Forks; Cowan Creek; and Berry Creek) to the San Gabriel River (Pierce 2011a, p. 2) and from two caves (aquatic, subterranean locations) in Williamson County, Texas. A groundwater divide between the South Fork of the San Gabriel River and Brushy Creek to the south likely creates the division between the ranges of the Jollyville Plateau and Georgetown salamanders (Williamson County 2008, p. 3-34).

The Service is currently aware of 17 Georgetown salamander localities (15 in or around a spring opening and 2 in caves). We have recently received confirmation that Georgetown salamanders occur at two additional spring sites (Hogg Hollow II Spring and Garey Ranch Spring) (Covey 2013, pers. comm., Covey 2014, pers. comm.) This species has not been observed in more than 20 years at San Gabriel Spring and more than 10 years at Buford Hollow Spring, despite several survey efforts to find it (Chippindale
et al.
2000, p. 40, Pierce 2011b, c, Southwestern University, pers. comm.). We are unaware of any population surveys in the last 10 years from a number of sites (such as Cedar Breaks Hiking Trail, Shadow Canyon, and Bat Well). Georgetown salamanders continue to be observed at the remaining 12 sites (Avant Spring, Swinbank Spring, Knight Spring, Twin Springs, Cowan Creek Spring, Cedar Hollow Spring, Cobbs Spring/Cobbs Well, Garey Ranch Spring, Hogg Hollow Spring, Hogg Hollow II Spring, Walnut Spring, and Water Tank Cave) (Pierce 2011c, pers. comm.; Gluesenkamp 2011a, TPWD, pers. comm.).

Recent mark-recapture studies suggest a population size of 100 to 200 adult salamanders at Twin Springs, with a similar population estimate at Swinbank Spring (Pierce 2011a, p. 18). Population sizes at other sites are unknown, but visual surface counts result in low numbers (Williamson County 2008, pp. 3-35). In fact, through a review of survey data available in our files and provided during the peer review and public comment period for the proposed rule, we found that the highest numbers observed at each of the other spring sites during the last 10 years is less than 50 (less than 5 salamanders at Avant Spring, Bat Well Cave, Cobbs Spring/CobbsWell, Shadow Canyon, and Walnut Spring; 0 salamanders at Buford Hollow Spring and San Gabriel Spring). There are other springs in Williamson County that may support Georgetown salamander populations, but access to the private lands where these springs are found has not been allowed, which has prevented surveys being done at these sites (Williamson County 2008, pp. 3-35).

Surface-dwelling Georgetown salamanders inhabit spring runs, riffles, and pools with gravel and cobble rock substrates (Pierce
et al.
2010, pp. 295-296). This species prefers larger cobble and boulders to use as cover (Pierce
et al.
2010, p. 295). Georgetown salamanders are found within 164 ft (50 m) of a spring opening (Pierce
et al.
2011a, p. 4), but they are most abundant within the first 16.4 ft (5 m) (Pierce
et al.
2010, p. 294). However, Jollyville Plateau salamanders, a closely related species, have been found farther from a spring opening in the Bull Creek drainage. A recent study using mark-recapture methods found marked individuals moved up to 262 ft (80 m) both upstream and downstream from the Lanier Spring outlet (Bendik 2013, pers. comm.). This study demonstrates that
Eurycea
salamanders in central Texas can travel greater distances from a discrete spring opening than previously thought, including upstream areas, if suitable habitat is present.

The water chemistry of Georgetown salamander habitat is constant year-round in terms of temperature and dissolved oxygen (Pierce
et al.
2010, p. 294, Biagas
et al.
2012, p. 163). Although some reproduction occurs year-round, recent data indicate that Georgetown salamanders breed mostly in winter and early spring (Pierce 2012, p. 8; Pierce and McEntire 2013, p. 6). The cave sites (Bat Well and Water Tank Cave) and the subterranean portion of Cobbs Well where this species is known to occur have been less studied than its surface habitat; therefore, the quality and extent of their subterranean habitats are not well understood.

Salado Salamander

The Salado salamander has reduced eyes compared to other spring-dwelling
Eurycea
species in north-central Texas and lacks well-defined melanophores (pigment cells that contain melanin). It has a relatively long and flat head, and a blunt and rounded snout. The upper body is generally grayish-brown with a slight cinnamon tinge and an irregular pattern of tiny, light flecks. The underside is pale and translucent. The end portion of the tail generally has a well-developed fin on top, but the bottom tail fin is weakly developed (Chippindale
et al.
2000, p. 42).

The Salado salamander is known historically from four spring sites near the village of Salado, Bell County, Texas: Big Boiling Springs (also known as Main, Salado, or Siren Springs), Lil' Bubbly Springs, Lazy Days Fish Farm Springs (also known as Critchfield Springs), and Robertson Springs (Chippindale
et al.
2000, p. 43; TPWD 2011, pp. 1-2). These springs bubble up through faults in the Northern Segment

of the Edwards Aquifer and associated limestone along Salado Creek (Brune 1975, p. 31). The four spring sites all contribute to Salado Creek. Under Brune's (1975, p. 5) definition, which identifies springs depending on flow, all sites are considered small (4.5 to 45 gallons per minute [17 to 170 liters per minute]) to medium springs (45 to 449 gallons per minute [170 to 1,1700 liters per minute]). Two other spring sites (Benedict and Anderson Springs) are located downstream from Big Boiling Springs and Robertson Springs. These springs have been surveyed by TPWD periodically since June 2009, but no salamanders have been found (Gluesenkamp 2010, TPWD, pers. comm.). In August 2009, TPWD discovered a population of salamanders at a new site (Solana Spring #1) farther upstream on Salado Creek in Bell County, Texas (TPWD 2011, p. 2). Salado salamanders were recently confirmed at two additional spring sites (Cistern and Hog Hollow Springs) on the Salado Creek in March 2010 (TPWD 2011, p. 2). In total, the Salado salamander is currently known from seven springs. A groundwater divide between Salado Creek and Berry Creek to the south likely creates a division between the ranges of the Georgetown and Salado salamander (Williamson County 2008, p. 3-34).

Of the two salamander species, Salado salamanders have been observed the least. Biologists were unable to observe this species in its type locality (location from which a specimen was first collected and identified as a species) despite over 20 visits to Big Boiling Springs that occurred between 1991 and 1998 (Chippindale
et al.
2000, p. 43). Likewise, TPWD surveyed this site weekly from June 2009 until May 2010, and found one salamander (Gluesenkamp 2010, TPWD, pers. comm.) at a spring outlet locally referred to as “Lil' Bubbly” located near Big Boiling Springs. One additional unconfirmed sighting of a Salado salamander in Big Boiling Springs was reported in 2008, by a citizen of Salado, Texas. In 2009, TPWD was granted access to Robertson Springs to survey for the Salado salamander. This species was reconfirmed at this location in February 2010 (Gluesenkamp 2010, TPWD, pers. comm.). In the fall of 2012, all of the spring outlets near the Village of Salado were thoroughly searched over a period of two months using a variety of sampling methods, and no Salado salamanders were found (Hibbitts 2013, p. 2). Salado salamander populations appear to be larger at spring sites upstream of the Village of Salado, probably due to the higher quality of the habitat (Gluesenkamp 2011b, TPWD, pers. comm.).

Summary of Comments and Recommendations

We requested comments from the public on the proposed listing for Georgetown salamander and Salado salamander during three comment periods. The first comment period associated with the publication of the proposed rule (77 FR 50768) opened on August 22, 2012, and closed on October 22, 2012, during which we held public meetings and hearings on September 5 and 6, 2012, in Round Rock and Austin, Texas, respectively. We reopened the comment period on the proposed listing rule from January 25, 2013, to March 11, 2013 (78 FR 5385). During our 6-month extension on the final determination for the Georgetown and Salado salamanders, we reopened the comment period from August 20, 2013, to September 19, 2013 (78 FR 51129). On January 7, 2014, we reopened the comment period and announced the availability of the City of Georgetown's final ordinance for water quality and urban development (79 FR 800). We reopened the comment period to allow all interested parties an opportunity to comment simultaneously on the proposed rule and the effect of the new city ordinance on the threats to the species. That comment period closed on January 22, 2014. We also contacted appropriate Federal, state, and local agencies; scientific organizations; and other interested parties and invited them to comment on the proposed rule during these comment periods.

We received a total of approximately 483 comments during the open comment periods for the proposed listing and critical habitat rules. All substantive information provided during the comment periods has been incorporated directly into the final listing rule for the salamanders and is addressed below in our response to comments. Comments from peer reviewers and state agencies are grouped separately below. Comments received are grouped into general issues specifically relating to the proposed listing for the salamander species. Beyond the comments addressed below, several commenters submitted additional reports and references for our consideration, which were reviewed and incorporated into this final listing rule as appropriate.

Peer Review

In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinions from 22 knowledgeable individuals with scientific expertise concerning the hydrology, taxonomy, and ecology that is important to these salamander species. We requested expert opinions from taxonomists specifically to review the proposed rule in light of an unpublished report by Forstner (2012, entire) that questioned the taxonomic validity of the four central Texas salamanders as separate species. We received responses from 13 of the peer reviewers.

During the first comment period, we received some contradictory public comments, and we also found new information relative to the listing determination. For these reasons, we conducted a second peer review on: (1) Salamander demographics and (2) urban development and stream habitat. During this second peer review, we solicited expert opinions from 20 knowledgeable individuals with expertise in the two areas identified above. We received responses from eight peer reviewers during this second review. The peer reviewers generally concurred with our methods and conclusions and provided additional information, clarifications, and suggestions to improve the final listing and critical habitat rule. Peer reviewer comments are addressed in the following summary and incorporated into the final rule as appropriate.

Peer Reviewer Comments

Taxonomy

(1)
Comment:
Most peer reviewers stated that the best available scientific information was used to develop the proposed rule and the Service's analysis of the available information was scientifically sound. Further, most reviewers stated that our assessment that these are four distinct species and our interpretation of literature addressing threats (including reduced habitat quality due to urbanization and increased impervious cover) to these species was well researched. However, some researchers suggested that further research would strengthen or refine our understanding of these salamanders. For example, one reviewer stated that the Jollyville Plateau salamander taxonomy was supported by weak but suggestive evidence, and therefore, it needed more study. Another reviewer thought there was evidence of missing descendants in the group that included the Jollyville Plateau and Georgetown salamanders in the enzyme analysis presented in the original species descriptions (Chippindale
et al.
2000, entire).

Our Response:
Peer reviewers' comments indicate that we used the best available science, and we correctly

interpreted that science as recognizing the central Texas salamanders as four separate species. In the final listing rule, we continue to recognize the Austin blind, Jollyville Plateau, Georgetown, and Salado salamanders as four distinct and valid species. However, we acknowledge that the understanding of the taxonomy of these salamander species can be strengthened by further research.

(2)
Comment:
Forstner (2012, pp. 3-4) used the size of geographic distributions as part of his argument for the existence of fewer species of
Eurycea
in Texas than are currently recognized. Several peer reviewers commented that they saw no reason for viewing the large number of
Eurycea
species with small distributions in Texas as problematic when compared to the larger distributions of
Eurycea
species outside of Texas. They stated that larger numbers and smaller distributions of Texas
Eurycea
species are to be expected given the isolated spring environments that they inhabit within an arid landscape. Salamander species with very small ranges are common in several families and are usually restricted to island, mountain, or cave habitats.

Our Response:
See our response to comment 1.

(3)
Comment:
Forstner (2012, pp. 15-16) used results from Harlan and Zigler (2009), indicating that levels of genetic variation within the eastern species the spotted-tail salamander (
E. lucifuga
) are similar to those among six currently recognized species of Texas
Eurycea,
as part of his argument that there are fewer species in Texas than currently recognized. Several peer reviewers said that these sorts of comparisons can be very misleading in that they fail to take into consideration differences in the ages, effective population sizes, or population structure of the units being compared. The delineation of species should be based on patterns of genetic variation that influence the separation (or lack thereof) of gene pools rather than solely on the magnitude of genetic differences, which can vary widely within and between species groups.

Our Response:
See our response to comment 1.

(4)
Comment:
Several peer reviewers stated that the taxonomic tree presented in Forstner (2012, pp. 20, 26) is difficult to evaluate because of the following reasons: (1) No locality information is given for the specimens; (2) it disagrees with all trees in other studies (which seem to be largely congruent with one another), including that in Forstner and McHenry (2010, pp. 13-16) with regard to monophyly (a group in which the members are comprised of all of the descendants from a common ancestor) of several of the currently recognized species; and (3) the tree is only a gene tree, presenting sequence data on a single gene, which provides little or no new information on species relationships of populations.

Our Response:
See our response to comment 1.

(5)
Comment:
Peer reviewers generally stated that Forstner (2012, pp. 13-14) incorrectly dismisses morphological data that have been used to recognize some of the Texas
Eurycea
species on the basis that it is prone to convergence (acquisition of the same biological trait in unrelated lineages) and, therefore, misleading. The peer reviewers commented that it is true that similarities in characters associated with cave-dwelling salamanders can be misleading when suggesting that the species possessing those characters are closely related. However, this in no way indicates that the reverse is true; that is, indicating differences in characters is not misleading in identifying separate species.

Our Response:
See our response to comment 1.

Impervious Cover

(6)
Comment:
The 10 percent impervious cover threshold may not be protective of salamander habitat based on a study by Coles
et al.
(2012, pp. 4-5), which found a loss of sensitive species due to urbanization and that there was no evidence of a resistance threshold to invertebrates that the salamanders prey upon. A vast amount of literature indicates that 1 to 2 percent impervious cover can cause habitat degradation, and, therefore, the 10 percent threshold for impervious cover will not be protective of these species.

Our Response:
We recognize that low levels of impervious cover in a watershed may have impacts on aquatic life, and we have incorporated results of these studies into the final listing rule. However, we are aware of only one peer-reviewed study that examined watershed impervious cover effects on salamanders in central Texas, and this study found impacts on salamander density in watersheds with over 10 percent impervious cover (Bowles
et al.
2006, pp. 113, 117-118). Because this impervious cover study was done locally, we are using 10 percent as a current reference point to categorize watersheds that are impacted in terms of salamander density.

(7)
Comment:
While the Service's impervious cover analysis assessed impacts on stream flows and surface habitat, it neglected to address impacts over the entire recharge zone of the contributing aquifers on spring flows in salamander habitat. Also, the surface watersheds analyzed in the proposed rule are irrelevant because these salamanders live in cave streams and spring flows that receive groundwater. Without information on the groundwater recharge areas, the rule should be clear that the surface watersheds are only an approximation of what is impacting the subsurface drainage basins.

Our Response:
We acknowledge that the impervious cover analysis is limited to impacts on the surface watershed. Because the specific groundwater recharge areas of individual springs are unknown, we cannot accurately assess the current or future impacts on these areas. However, we recognize subsurface flows as another avenue for contaminants to reach the salamander sites, and we tried to make this clearer in the final rule.

(8)
Comment:
Several of the watersheds analyzed for impervious cover in the proposed rule were overestimated. The sub-basins in these larger watersheds need to be analyzed for impervious cover impacts.

Our Response:
We have refined our impervious cover analysis in this final listing rule to clarify the surface watersheds of individual spring sites. Our final impervious cover report containing this refined analysis is available on the Internet at
http://www.regulations.gov
under Docket No. FWS-R2-ES-2012-0035 and at
http://www.fws.gov/southwest/es/AustinTexas
/.

Threats

(9)
Comment:
One peer reviewer stated that the threat to these species from over collection for scientific purposes may be understated.

Our Response:
We have reevaluated the potential threat of overutilization for scientific purposes and have incorporated a discussion of this under Factor B “
Overutilization for Commercial, Recreational, Scientific, or Educational Purposes.”
We recognize that removing individuals from small, localized populations in the wild without any proposed plans or regulations to restrict these activities could increase the population's vulnerability of extinction and decrease its resiliency and ability to withstand stochastic events. However, we do not consider overutilization from collecting salamanders in the wild to be substantial enough to be a threat by itself; however, it may cause population declines and could negatively impact

both salamander species in combination with other threats.

Salamander Demographics

(10)
Comment:
Several peer reviewers agreed that COA's salamander survey data were generally collected and analyzed appropriately and that the results are consistent with the literature on aquatic species' responses to urbanizing watersheds. Three reviewers had some suggestions on how the data analysis could be improved, but they also state that COA's analysis is the best scientific data available, and alternative methods of analysis would not likely change the conclusions.

Our Response:
Because the peer reviewers examined COA's salamander demographic data, as well as SWCA Environmental Consultants' analysis of the COA's data, and generally agreed that the COA's data was the best information available, we continue to rely upon this data set in the final listing rule.

(11)
Comment:
Two peer reviewers pointed out that water samples were collected by SWCA during a period of very low rainfall and, therefore, under represent the contribution of water influenced by urban land cover. The single sampling effort of water and sediment at the eight sites referenced in the SWCA report do not compare in scope and magnitude to the extensive studies referenced from the COA. The numerous studies conducted (and referenced) within the known ranges of the salamander species provide scientific support at the appropriate scale for recent and potential habitat degradation due to urbanization. One peer reviewer pointed out that if you sort the spring sites SWCA sampled into “urbanized” and “rural” categories, the urban sites generally have more degraded water quality than the rural sites, in terms of nitrate, nitrite,
Escherichia coli
(
E. coli
) counts, and fecal coliform bacteria counts.

Our Response:
The peer reviewers made valid arguments that the SWCA (2012, pp. 21-24) did not present convincing evidence that overall water quality at salamander sites in Williamson County is good or that urbanization is not impacting the water quality at these sites. Water quality monitoring based on one or a few samples is not necessarily reflective of conditions at the site under all circumstances that the salamanders are exposed to over time. Based on this assessment, we continued to rely upon the best scientific information available in published literature that indicate water quality will decline as urbanization within the watershed increases.

(12)
Comment:
The SWCA report indicates that increasing conductivity is related to drought. (Note: Conductivity is a measure of the ability of water to carry an electrical current and can be used to approximate the concentration of dissolved inorganic solids in water that can alter the internal water balance in aquatic organisms, affecting the salamanders' survival. Conductivity levels in the Edwards Aquifer are naturally low. As ion concentrations such as chlorides, sodium, sulfates, and nitrates rise, conductivity will increase. The stability of the measured ions makes conductivity an excellent monitoring tool for assessing the impacts of urbanization to overall water quality. High conductivity has been associated with declining salamander abundance.). While SWCA's report notes lack of rainfall as the dominant factor in increased conductivity, the confounding influence of decreases in infiltration and increases in sources of ions as factors associated with urbanization and changes in water quality in these areas is not addressed by SWCA. Higher conductivity in urban streams is well documented and was a major finding of the U.S. Geological Survey (USGS) urban land use studies (Coles
et al.
2012). Stream conductivity increased with increasing urban land cover in every metropolitan area studied.

Our Response:
While drought may result in increased conductivity, increased conductivity is also a reflection of increased urbanization. We incorporated information from the study by Coles
et al.
(2012) in the final listing rule, and we continue to include conductivity as a measure of water quality.

(13)
Comment:
One peer reviewer stated that SWCA's criticisms of COA's linear regression analysis, general additive model, and population age structure were not relevant and were unsupported. In addition, peer reviewers agreed that COA's mark-recapture estimates are robust and highly likely to be correct. Three peer reviewers agreed that SWCA misrepresented the findings of Luo (2010) and stated that this thesis does not invalidate the findings of COA.

Our Response:
Because the peer reviewers examined COA's data, as well as SWCA's analysis of the COA's data, and generally agreed that the COA's data was the best information available, we continue to rely upon this data set in the final listing rule.

(14)
Comment:
One peer reviewer stated that the long-term data collected by the COA on the Jollyville Plateau salamander were simple counts that serve as indices of relative population abundance and are not a measure of absolute abundance. This data assumes that the probability of observing salamanders remains constant over time, season, and among different observers. This assumption is often violated, which results in unknown repercussions on the assessment of population trends. Therefore, the negative trend observed in several sites could be due to a real decrease in population absolute abundance, but could also be related to a decrease in capture probabilities over time (or due to an interaction between these two factors). Absolute population abundance and capture probabilities should be estimated in urban sites using the same methods implemented at rural sites by COA. However, even in the absence of clear evidence of local population declines of Jollyville Plateau salamanders, the proposed rule was correct in its assessment because there is objective evidence that urbanization negatively impacts the density of
Eurycea
salamanders (for example, Barrett
et al.
2010).

Our Response:
We recognize that the long-term survey data of Jollyville Plateau salamanders using simple counts may not give conclusive evidence on the true population status at each site. However, based on the threats and evidence from scientifically peer-reviewed literature, we conclude that the declines in counts seen at urban Jollyville Plateau salamander sites represent the best available information on the status of the Jollyville Plateau salamander and are likely representative of real declines in the population. We expect similar responses by Georgetown and Salado salamanders.

(15)
Comment:
One peer reviewer had similar comments on COA salamander counts and relating them to populations. They stated that the conclusion of a difference in salamander counts between sites with high and low levels of impervious cover is reasonable based on COA's data. However, this conclusion is not about salamander populations, but instead about the counts. The COA's capture-mark-recapture analyses provide strong evidence of both non-detection and substantial temporary emigration, findings consistent with other studies of salamanders in the same family as the Jollyville Plateau salamander. This evidence cautions against any sort of analysis that relies on raw count data to draw inferences about populations.

Our Response:
See our response to the previous comment.

(16)
Comment:
The SWCA (2012, pp. 70-76) argues that declines in salamander counts can be attributed to declines in rainfall during the survey period and not watershed urbanization. However, one peer reviewer stated that SWCA provided no statistical analysis to validate this claim and misinterpreted the conclusions of Gillespie (2011) to support their argument. A second peer reviewer agrees that counts of salamanders are related to natural wet and dry cycles but points out that COA has taken this effect into account in their analyses. Another peer reviewer points out that this argument contradicts SWCA's (2012) earlier claim that COA's salamander counts are unreliable data. If the data were unreliable, they probably would not correlate to environmental changes.

Our Response:
Although rainfall is undoubtedly important to these strictly aquatic salamander species, the best scientific information suggests that rainfall is not the only factor driving salamander population fluctuations. In the final listing rule, we continue to rely upon this evidence as the best scientific and commercial information available, which suggests that urbanization is also a large factor influencing declines in salamander counts.

Regarding comments from SWCA on the assessment of threats, peer reviewers made the following comments:

(17)
Comment:
SWCA's (2012, pp. 84-85) summary understates what is known about the ecology of
Eurycea
species and makes too strong of a conclusion about the apparent “coexistence with long-standing human development.” Human development and urbanization is an incredibly recent stressor in the evolutionary history of the central Texas
Eurycea,
and SWCA's assertion that the
Eurycea
will be “hardy and resilient” to these new stressors is not substantiated with any evidence. In direct contradiction to this assertion, SWCA (2012, p. 83) explains how one population of Georgetown salamanders was extirpated due to municipal groundwater pumping drying the spring.

(18)
Comment:
SWCA (2012, p. 7) states that, “Small population size and restricted distribution are not among the five listing criteria and do not of themselves constitute a reason for considering a species at risk of extinction.” To the contrary, even though the salamanders may naturally occur in small isolated populations, small isolated populations and the inability to disperse between springs should be considered under listing criteria E as a natural factor affecting the species' continued existence. In direct contradiction, SWCA (2012, p. 81) later states that, “limited dispersal ability (within a spring) may increase the species' vulnerability as salamanders may not move from one part of the spring run to another when localized habitat loss or degradation occurs.” It is well known that small population size and restricted distributions make populations more susceptible to selection or extinction due to stochastic events. Small population size can also affect population density thresholds required for successful mating.

(19)
Comment:
SWCA (2012, p. v) argues that the Jollyville Plateau salamander is not in immediate danger of extinction because, “over 60 of the 90-plus known Jollyville Plateau salamander sites are permanently protected within preserve areas, and 4 of the 16 known Georgetown salamander sites are permanently protected (and establishment of additional protected sites is being considered).” This statement completely ignores the entire aquifer recharge zone, which is not included in critical habitat. Furthermore, analysis of the COA's monitoring and water quality datasets clearly demonstrate that, even within protected areas, there is deterioration of water quality and decrease in population size of salamanders.

(20)
Comment:
SWCA (2012, p. 11) criticizes the Service and the COA for not providing a direct cause and effect relationship between urbanization, nutrient levels, and salamander populations. There is, in fact, a large amount of peer-reviewed literature on the effects of pollutants and deterioration of water quality on sensitive macroinvertebrate species as well as on aquatic amphibians. In the proposed rule, the Service cites just a small sampling of the available literature regarding the effects of pollutants on the physiology and indirect effects of urbanization on aquatic macroinvertebrates and amphibians. In almost all cases, there are synergistic and indirect negative effects on these species that may not have one single direct cause. There is no ecological requirement that any stressor (be it a predator, a pollutant, or a change in the invertebrate community) must be a direct effect to threaten the stability or long-term persistence of a population or species. Indirect effects can be just as important, especially when many are combined.

Our Response to Comments 17-20:
We included SWCA's (2012) report as part of the information we asked for peer reviewers to consider. The peer reviewers generally agreed that we used the best information available in our proposed listing rule.

(21)
Comment:
One reviewer stated that, even though there is detectable gene flow between populations, it may be representative of subsurface connections in the past, rather than current population interchange. However, dispersal through the aquifer is possible even though there is currently no evidence that these species migrate. Further, they stated that there is no indication of a metapopulation structure where one population could recolonize another that had gone extinct.

Our Response:
We acknowledge that more study is needed to determine the nature and extent of the dispersal capabilities of the Georgetown and Salado salamanders. It is plausible that populations of these species could extend through subterranean habitat. However, subsurface movement is likely to be limited by the highly dissected nature of the aquifer system, where spring sites can be separated from other spring sites by large canyons or other physical barriers to movement. Dye-trace studies have demonstrated that some Jollyville Plateau salamander sites located miles apart are connected hydrologically (Whitewater Cave and Hideaway Cave) (Hauwert and Warton 1997, pp. 12-13), but it remains unclear if salamanders are travelling between those sites. We have some indication that populations could be connected through subterranean water-filled spaces, although we are unaware of any information on the frequency of movements and the actual nature of connectivity among populations.

Comments From States

Section 4(i) of the Act states, “the Secretary shall submit to the State agency a written justification for his failure to adopt regulations consistent with the agency's comments or petition.” Comments received from all State agencies and entities in Texas regarding the proposal to list the Georgetown and Salado salamanders are addressed below.

(22)
Comment:
Chippindale (2010) demonstrated that it is possible for Jollyville Plateau salamanders to move between sites in underground conduits. Close genetic affinities between populations in separate watersheds on either side of the RM 620 suggest that these populations may be connected hydrologically. Recent studies (Chippindale 2011 and 2012, in prep) indicate that gene flow among salamander populations follows groundwater flow routes in some cases and that genetic exchange occurs both

horizontally and vertically within an aquifer segment.

Our Response:
We agree that genetic evidence suggests subsurface hydrological connectivity exist between sites at some point in time, but we are unable to conclude if this connectivity occurred in the past or if it still occurs today without more hydrogeological studies or direct evidence of salamander migration from mark-recapture studies. Also, one of our peer reviewers stated that this genetic exchange is probably representative of subsurface connection in the past (see comment 21 above).

(23)
Comment:
There were insufficient data to evaluate the long-term flow patterns of the springs and creeks, and the correlation of flow, water quality, habitat, ecology, and community response. Current research in Williamson County indicates that water and sediment quality remain good with no degradation, no elevated levels of toxins, and no harmful residues in known springs.

Our Response:
We have reviewed the best available scientific and commercial information in making our final listing determination. We sought comments from independent peer reviewers to ensure that our designation is based on scientifically sound data, assumptions, and analysis. And the peer reviewers stated that our proposed rule was based on the best available scientific information. Additionally, recent research on water quality in Williamson County springs was considered in our listing rule. The peer reviewers agreed that these data did not present convincing evidence that overall water quality at salamander sites in Williamson County is good or that urbanization is not impacting the water quality at these sites (see Comment 19 above).

(24)
Comment:
The listing will have negative impacts to private development and public infrastructure.

Our Response:
In accordance with the Act, we cannot consider possible economic impacts in making a listing determination. However, Section 4(b)(2) of the Act states that the Secretary shall designate and make revisions to critical habitat on the basis of the best available scientific data after taking into consideration the economic impact, national security impact, and any other relevant impact of specifying any particular area as critical habitat. Economic impacts are not taken into consideration as part of listing determinations.

(25)
Comment:
It was suggested that there are adequate regulations in Texas to protect the Georgetown and Salado salamanders and their respective habitats. The overall programs to protect water quality—especially in the watersheds of the Edwards Aquifer region—are more robust and protective than suggested by the Service's descriptions of deficiencies. The Service overlooks the improvements in the State of Texas and local regulatory and incentive programs to protect the Edwards Aquifer and spring-dependent species over the last 20 years. Texas has extensive water quality management and protection programs that operate under state statutes and the Federal Clean Water Act. These programs include: Surface Water Quality Monitoring Program, Clean Rivers Program, Water Quality Standards, Texas Pollutant Discharge Elimination System (TPDES) Stormwater Permitting, Total Maximum Daily Load Program, Nonpoint Source Program, Edwards Aquifer Rules, and Local Ordinances and Rules (San Marcos Ordinance and COA Rules). Continuing efforts at the local, regional, and state level will provide a more focused and efficient approach for protecting these species than Federal listing.

Our Response:
Section 4(b)(1)(A) of the Act requires us to take into account those efforts being made by a state or foreign nation, or any political subdivision of a state or foreign nation, to protect such species, and we fully recognize the contributions of the state and local programs. We consider relevant Federal, state, and tribal laws and regulations when developing our threats analysis. Regulatory mechanisms may preclude the need for listing if we determine such mechanisms address the threats to the species such that listing is no longer warranted. However, the best available scientific and commercial data available at the time of the proposed rule supported our initial determination that existing regulations and local ordinances were not adequate to remove all of the threats to the Georgetown and Salado salamanders. Since that time, the City of Georgetown approved a new ordinance designed to reduce the threats to the Georgetown salamander. We have added further discussion of existing regulations and ordinances under Factor D in the final listing rule, and we have considered these new ordinances in our threats analysis below.

(26)
Comment:
The requirement in the Edwards Aquifer Rules for wastewater to be disposed of on the recharge zone by land application is an important and protective practice for aquifer recharge and a sustainable supply of groundwater. Permits for irrigation of wastewater are fully evaluated and conditioned to require suitable vegetation and sufficient acreage to protect water quality.

Our Response:
Based on the best available science, wastewater disposal on the recharge zone by land application can contribute to water quality degradation in surface waters and the underground aquifer. Previous studies have demonstrated negative impacts to water quality (increases in nitrate levels) at Barton Springs (Mahler
et al.
2011, pp. 29-35) and within streams (Ross 2011, pp. 11-21) that were likely associated with the land application of wastewater.

(27)
Comment:
A summary of surface water quality data for streams in the watersheds of the salamanders was provided, and a suggestion was made that sampling data indicated high-quality aquatic life will be maintained despite occasional instances where parameters exceeded criteria or screening levels.

Our Response:
In reviewing the 2010 and 2012 Texas Water Quality Integrated Reports prepared by the Texas Commission on Environmental Quality (TCEQ), the Service identified 3 of 7 (43 percent) and 2 of 2 (100 percent) stream segments located within surface drainage areas occupied by the Georgetown and Salado salamanders respectively, which contained measured parameters within water samples that exceeded screening level criteria. These included “screening level concerns” for parameters such as nitrate, dissolved oxygen, and impaired benthic communities. Water quality data collected and summarized in TCEQ reports supports concerns for the potential for water quality degradation within the surface drainage areas occupied by the salamanders. This information is discussed under
Summary of Factors Affecting the Species
in this final listing rule.

(28)
Comment:
The City of Georgetown ordinance reduces the threats to surface habitat conditions and water quality for the Georgetown salamander.

Our response:
The Service agrees that the City of Georgetown ordinance will reduce some of the threats to the Georgetown salamander. We have provided a discussion on the effectiveness of the City of Georgetown's ordinance in reducing the threats to the Georgetown salamander under
Summary of Factors Affecting the Species
below in the final listing rule.

Public Comments

Existing Regulatory Mechanisms

(29)
Comment:
The Service improperly discounts the value of

TCEQ's Optional Enhanced Measures by concluding that, because they are optional as to non-listed species, “take” prohibitions do not apply and they are not a regulatory mechanism. However, in February 14, 2005, the Service stated in a letter to Governor Rick Perry that implementation of the Enhanced Measures would result in “no take” of various aquatic species, including the Georgetown salamander.

Our Response:
With the listing of the Georgetown and Salado salamanders, the Act and its implementing regulations set forth a series of general prohibitions and exceptions that apply to all endangered and threatened wildlife. The prohibitions of section 9(a)(2) of the Act, codified at 50 CFR 17.21 and 50 CFR 17.31, make it illegal for any person subject to the jurisdiction of the United States to take (includes harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect; or to attempt any of these), import, export, ship in interstate commerce in the course of commercial activity, or sell or offer for sale in interstate or foreign commerce any listed species. Under the Lacey Act (18 U.S.C. 42-43; 16 U.S.C. 3371-3378), it is also illegal to possess, sell, deliver, carry, transport, or ship any such wildlife that has been taken illegally. We may issue permits to carry out otherwise prohibited activities involving endangered and threatened wildlife species under certain circumstances, but such a permit must be issued for scientific purposes, to enhance the propagation or survival of the species, and for incidental take in connection with otherwise lawful activities. The Service's 2005 and 2007 letters to Governor Rick Perry were made prior to listing of the Georgetown and Salado salamanders and do not constitute a permit that allows for take under the Act.

We have changed the wording in the final listing rule to more accurately reflect our opinion that the Optional Enhanced Measures may provide protection to the species, but do not constitute a regulatory mechanism because they are voluntary. These measures were intended to be used for the purpose of avoiding harm to the identified species from water quality impacts, not to address any of the other threats to the Georgetown salamander. TCEQ reported that only 17 Edwards Aquifer applications have been approved under the Optional Enhanced Measures between February 2005 and May 2012, and the majority of these applications were for sites in the vicinity of Dripping Springs, Texas, which would not pertain to the Georgetown salamander (Beatty 2012, TCEQ, pers. comm.).

(30)
Comment:
The Service's February 14, 2005, and September 4, 2007, letters to Governor Rick Perry concurred that non-federal landowners and other non-federal managers using the voluntary measures in Appendix A to the TCEQ technical guidance manual for the Edwards Aquifer Protection Program would have the support of the Service that “no take” under the Act would occur unless projects met specific criteria listed in the letters.

Our Response:
See our response to comment (29) above.

(31)
Comment:
Many commenters expressed concern that the Service had not adequately addressed all of the existing regulatory mechanisms and programs that provided protection to the salamanders. In addition, many of the same commenters believed there were adequate state, Federal, and local regulatory mechanisms to protect the salamanders and their aquatic habitats.

Our Response:
Section 4(b)(1)(A) of the Act requires us to take into account those efforts being made by a state or foreign nation, or any political subdivision of a state or foreign nation, to protect such species. Under
D. The Inadequacy of Existing Regulatory Mechanisms
in the final listing rule, we provide an analysis of the inadequacy of existing regulatory mechanisms. During the comment period, we sought out and were provided information on several local, state, and Federal regulatory mechanisms that we had not considered when developing the proposed rule. We have reviewed these mechanisms and have included them in our analysis under
D. The Inadequacy of Existing Regulatory Mechanisms
in the final listing rule. In addition, during the 6-month extension the City of Georgetown approved a new ordinance designed to reduce the threats to the Georgetown salamander. We have included this ordinance in our discussion under
Summary of Factors Affecting the Species
below in the final listing rule.

Protections

(32)
Comment:
The Service fails to consider existing local conservation measures and habitat conservation plans (HCPs) that benefit the salamanders. While the salamanders are not covered in most of these HCPs, some commenters believe that measures are in place to mitigate any imminent threats to the species. The Service overlooks permanent conservation actions undertaken by both public and private entities over the last two or more decades. The HCPs and water quality protection standards are sufficient to prevent significant habitat degradation.

Our Response:
In the final listing rule, we included a section titled “Conservation Efforts to Reduce Habitat Destruction, Modification, or Curtailment of Its Range” that describes existing conservation measures including the regional permit issued to the Williamson County Regional HCP. These conservation efforts and the manner in which they are helping to ameliorate threats to the species were considered in our final listing determination. The Service considered the amount and location of managed open space when analyzing impervious cover levels within each surface watershed (Service 2012, 2013). We also considered preserves when projecting how impervious cover levels within the surface watershed of each spring site would change in the future. These analyses included the benefits from open space as a result of several HCPs, including Buttercup Creek HCP, Balcones Canyonlands Conservation Plan, Lakeline Mall HCP, Concordia HCP, Four Points HCP, and Grandview Hills HCP. Of these, only the Williamson County HCP and Lakeline Mall HCP created open space within the range of the Georgetown salamander (no HCPs have established open space within the range of the Salado salamander). While these conservation lands contribute to the protection of the surface and subsurface watersheds, there are other factors contributing to the decline of the salamander's habitat. Other factors include, but are not limited to: (1) Other areas within the surface watershed that have high levels of impervious cover, which increases the overall percentage of impervious cover within the watershed; (2) potential for groundwater pollution from areas outside of the surface watershed; and (3) disturbance of the surface habitat of the spring sites themselves.

(33)
Comment:
Multiple commenters stated that the Georgetown salamander's known distribution is entirely contained within the jurisdictional boundaries of the Williamson County Regional HCP (RHCP) and is thusly already protected. The RHCP includes provisions for studying the Georgetown salamander and numerous conservation actions benefitting the species. To date, 47 entities have participated in the RHCP and the Williamson County Conservation Fund (WCCF) has permanently preserved 664 ac (269 ha) within 8 preserves. As part of the RHCP, a commitment was made to conduct a 5-year study of the Georgetown salamander and drafting of a

conservation strategy. In 2008, based on these actions, the Service reduced the listing priority category for the Georgetown salamander from a 2 to an 8.

Our Response:
We agree with the commenters that the RHCP permit area contains the entire range of the Georgetown salamander, and also includes a portion of the Jollyville Plateau salamander within its permit area. Furthermore, we agree that some of the land preserved by the RHCP as mitigation for the impacts of covered activities on endangered invertebrate species is contributing to protection of a limited amount of salamander habitat. However, the RHCP does not permit “take” of salamanders as covered species, accordingly the permit does not require mitigation for the impacts of the covered actions on any salamander species. The RHCP notes on page 4-19 that actions authorized by the RHCP for covered species “. . . may impact the Georgetown salamander by degrading water quality and quantity in springs and streams in the watersheds where the species occurs.” One of the RHCP's biological goals is to help conserve the salamanders by studying the Georgetown salamander's status, distribution, and conservation needs. In addition to a 5-year Georgetown salamander research and monitoring program, Williamson County committed to drafting a conservation strategy for the species, based on initial findings of the research, and coordinating a public education and outreach program. While this research to date has been incorporated in the final listing rule, the best available information supports our conclusion that the threats to the species are not ameliorated by the RHCP.

The listing priority number was lowered from a 2 to an 8 for the Georgetown salamander based on conservation actions by WCCF in 2008 (73 FR 75176, December 10, 2008). A listing priority of 8 indicates that there are imminent threats to the species, but the magnitude of these imminent threats is moderate to low.

(34)
Comment:
The proposed rule directly contradicts the Service's recent policy titled Expanding Incentives for Voluntary Conservation Actions Under the Act (77 FR 15352, March 15, 2012), which concerns the encouragement of voluntary conservation actions for non-listed species and is available at
http://www.gpo.gov/fdsys/pkg/FR-2012-03-15/pdf/2012-6221.pdf
.

Our Response:
The commenter did not specify how the proposed rule contradicts the Service's recent policy pronouncements concerning the encouragement of voluntary conservation actions for non-listed species. The recent policy pronouncements specifically state that voluntary conservation actions undertaken are unlikely to be sufficient to affect the need to list the species. However, if the species is listed and voluntary conservation actions are implemented, as outlined in policy pronouncements, the Service can provide assurances that if the conditions of a conservation agreement are met, the landowner will not be asked to do more, commit more resources, or be subject to further land use restrictions than agreed upon. We may also allow a prescribed level of incidental take by the landowner.

(35)
Comment:
Existing protective measures and current land-use conditions in the contributing zone of the Northern Segment of the Edwards Aquifer negate the justification for the proposed listing of the Salado salamander. It was the understanding of Bell County that the development of comprehensive conservation strategies or plans to protect species would be based on additional research that will be conducted in a cooperative effort involving state and Federal environmental agencies and local stakeholders. Consistent with the guidance of agency officials, Bell County and their partners held public hearings and entered into contractual agreements with experts. Fieldwork related to those studies is about to commence.

Our Response:
The Service appreciates the efforts of Bell County and their partners to conduct research and collect additional data to support the conservation of the Salado salamander. The Service is required to make a determination on the status of the Salado salamander based on the best available science at the time we make our listing decision. The Service looks forward to continuing to work with Bell County and all of our other partners to further the conservation of the Salado salamander. We anticipate the additional research and information being gathered by Bell County and others will be helpful in refining conservation strategies and adapting management for these species, based on this new information.

(36)
Comment:
The proposed rule cites the vested rights statute found in Chapter 245, Texas Local Government Code as a weakness in local and state regulations. Chapter 245 does not apply to state regulations. Under Chapter 245, a “regulatory agency” is defined as a political subdivision of the state such as a county, school district or municipality (Section 245.001(2) & (4), Texas Local Government Code). The Edwards Rules for the Contributing Zone revised in 1999 had a very narrow grandfathering provision from the new regulations: A project did not have to comply with the new rules if the project had all of the permits necessary to begin construction on June 1, 1999, and construction began by December 1, 1999. No projects can possibly exist that are grandfathered from the Edwards Rules for the contributing zone of the Edwards Aquifer.

Our Response:
We have revised this discussion in this final rule, as appropriate.

Listing Process and Policy

(37)
Comment:
Reducing the Listing Priority Number of the Georgetown salamander from 2 to 8 indicates no imminent threat to the species.

Our Response:
In the 2008 candidate notice of review, the listing priority number was lowered from 2 to 8. However, a listing priority of 8 indicates that there are imminent threats to the species, but the magnitude of these imminent threats is moderate to low.

(38)
Comment:
The Service is pushing these listings because of the legal settlement and not basing its decision on science and the reality of the existing salamander populations.

Our Response:
We are required by court-approved settlement agreements to remove the Georgetown and Salado salamanders from the candidate list within a specified timeframe. To remove these salamanders from the candidate list means to propose them for listing as endangered or threatened or to prepare a not-warranted finding. The Act requires us to determine whether a species warrants listing based on our assessment of the five listing factors described in the Act using the best available scientific and commercial information. We already determined, prior to the court settlement agreement, that the Georgetown and Salado salamanders warranted listing under the Act, but were precluded by the necessity to commit limited funds and staff to complete higher priority species actions. These salamanders have been included in our annual Candidate Notices of Review for multiple years, during which time scientific literature and data have and continue to indicate that these salamanders are detrimentally impacted by ongoing threats, and we continued to find that listing each species was warranted but precluded. While the settlement agreement has set a court-ordered timeline for rendering our final decision, our determination is still guided by the Act and its

implementing regulations considering the five listing factors and using the best available scientific and commercial information.

(39)
Comment:
Commenters requested that the Service extend the comment period for another 45 days after the first comment period. The commenters were concerned about the length of the proposed listing, which is very dense and fills 88 pages in the
Federal Register
, and that the public hearing was held only 2 weeks after the proposed rule was published. Commenters do not consider this enough time to read and digest how the Service is basing a listing decision that will have serious consequences for Williamson County. Furthermore, the 60-day comment period does not give the public enough time to submit written comments to such a large proposed rule.

Our Response:
The initial comment period for the proposed listing and critical habitat designation consisted of 60 days, beginning August 22, 2012, and ending on October 22, 2012. We reopened the comment period for an additional 45 days, beginning on January 25, 2013, and ending on March 11, 2013. During our 6-month extension on the final determination for the Georgetown and Salado salamanders, we reopened the comment period from August 20, 2013, to September 19, 2013 (78 FR 51129). On January 7, 2014, we reopened the comment period and announced the availability of the City of Georgetown's final ordinance for water quality and urban development (79 FR 800). We reopened the comment period to allow all interested parties an opportunity to comment simultaneously on the proposed rule and the effect of the new city ordinances on threats to the Georgetown salamander. That comment period closed on January 22, 2014. We consider the comment periods described above an adequate opportunity for public comment.

(40)
Comment:
The Service has openly disregarded a contractual agreement (RHCP) with Williamson County that provided for additional study, violating mandatory process under the Act. It was our understanding that the development of comprehensive conservation strategies or plans to protect the species would be based on additional research, which would be conducted in a cooperative effort involving state and Federal environmental agencies and local stakeholders. Williamson County has committed funds and entered into contractual agreements with respected experts to perform these additional baseline studies. The Service has violated a contractual agreement under the Act.

Our Response:
The RHCP is not a contract. By moving forward with a listing decision for the Georgetown and Salado salamanders, the Service has not violated any mandatory process under the Act or any contractual agreement with Williamson County. The RHCP was established in 2008 to provide incidental take coverage for the federally listed golden-cheeked warbler (
Dendroica chrysoparia
), black-capped vireo (
Vireo atricapilla
), Bone Cave harvestman (
Texella reyesi
), and Coffin Cave mold beetle (
Batrisodes texanus
). A number of conservation actions for the Georgetown salamander were planned in the RHCP, but the Georgetown salamander is not a covered species under the RHCP. One of the conservation actions is for WCCF to conduct a 5-year research and monitoring study for the Georgetown salamander, which was planned with the intention of preparing a Candidate Conservation Agreement with Assurances if the species was still a candidate at the end of the study. The RHCP does not include an agreement between the Service and Williamson County to delay the listing of the Georgetown salamander until the study is completed.

(41)
Comment:
One commenter expressed concern with the use of “unpublished” data in the proposed rule. It is important that the Service takes the necessary steps to ensure all data used in the listing and critical habitat designations are reliable, verifiable, and peer reviewed, as required by President Obama's 2009 directive for transparency and open government. In December of 2009, the Office of Management and Budget (OMB) issued clarification on the presentation and substance of data used by Federal agencies and required in its Information Quality Guidelines. Additionally under the OMB guidelines, all information disseminated by Federal agencies must meet the standard of “objectivity.” Additionally, relying on older studies instead of newer ones conflicts with the Information Quality Guidelines.

Our Response:
Our use of unpublished information and data does not contravene the transparency and open government directive. Under the Act, we are obligated to use the best available scientific and commercial information, including results from surveys, reports by scientists and biological consultants, various models, and expert opinion from biologists with extensive experience studying the salamanders and their habitat, whether published or unpublished. One element of the transparency and open government directive encourages executive departments and agencies to make information about operations and decisions readily available to the public. Supporting documentation used to prepare the proposed and final rules is available for public inspection, by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Austin Ecological Services Field Office, 10711 Burnet Rd., Suite 200, Austin, TX 78758.

Peer Review Process

(42)
Comment:
One commenter requested that the Service make the peer review process as transparent and objective as possible. The Service should make available the process and criteria used to identify peer reviewers. It is not appropriate for the Service to choose the peer review experts. For the peer review to be credible, the entire process including the selection of reviewers must be managed by an independent and objective party. We recommend that the peer review plan identify at least two peer reviewers per scientific discipline. Further, the peer reviewers should be identified.

Our Response:
To ensure the quality and credibility of the scientific information we use to make decisions, we have implemented a formal peer review process. Through this peer review process, we followed the guidelines for Federal agencies spelled out in the Office of Management and Budget (OMB) “Final Information Quality Bulletin for Peer Review” released December 16, 2004, and the Service's “Information Quality Guidelines and Peer Review” revised June 2012. Part of the peer review process is to provide information online about how each peer review is to be conducted. Prior to publishing the proposed listing and critical habitat rule for these salamanders, we posted a peer review plan on our Web site, which included information about the process and criteria used for selecting peer reviewers, and we posted the peer reviews on
http://www.regulations.gov
.

In regard to transparency, the OMB and Service's peer review guidelines mandate that we not conduct anonymous peer reviews. The guidelines state that we advise reviewers that their reviews, including their names and affiliations, and how we respond to their comments will be included in the official record for review, and once all the reviews are completed, their reviews will be available to the public. We followed the policies and standards for conducting

peer reviews as part of this rulemaking process.

(43)
Comment:
The results of the peer review process should be available to the public for review and comment well before the end of the public comment period on the listing decision. Will the public have an opportunity to participate in the peer review process?

Response:
As noted above, OMB and the Service's guidelines state that we make available to the public the peer reviewers' information, reviews, and how we respond to their comments once all reviews are completed. The peer reviews are completed at the time the last public comment period closes, and our responses to their comments are completed at the time the final listing decision is published in the
Federal Register
. All peer review process information is available upon request at this time and is available from the U.S. Fish and Wildlife Service, Austin Ecological Services Field Office, 10711 Burnet Rd, Suite 200, Austin, TX 78758. In addition, the peer reviews have been posted at
http://www.regulations.gov
.

(44)
Comment:
New information has been provided during the comment period. The generalized opinions of the initial peer reviewers regarding the proposed rule having the best available science is largely negated by the significant quantity of materials submitted by the public during the first two comment periods. In other words, the large quantity of additional information submitted into the record clearly demonstrates that the proposed rule did not reflect the best available scientific and commercial data. The final listing decision should be peer reviewed.

Response:
During the second public comment period, we asked peer reviewers to comment on new and substantial information that we received during the first comment period. We did not receive any new information during the second comment period that we felt rose to the level of needing peer review. Furthermore, as part of our peer review process, we asked peer reviewers not to provide comments or recommendations on the listing decision. Peer reviewers were asked to comment specifically on the quality of information and analyses used or relied on in the reviewed documents. In addition, they were asked to identify oversights, omissions, and inconsistencies; provide advice on reasonableness of judgments made from the scientific evidence; ensure that scientific uncertainties are clearly identified and characterized and that potential implications of uncertainties for the technical conclusions drawn are clear; and provide advice on the overall strengths and limitations of the scientific data used in the document.

(45)
Comment:
One commenter requested a peer review of the four central Texas salamanders' taxonomy and recommended that, to avoid any potential bias, peer reviewers not be from Texas or be authors or contributors of any works that the Service has or is relying upon to diagnose the four central Texas salamanders as four distinct species. This commenter also provided a list of four recommended scientists for the peer review on taxonomy.

Our Response:
We requested peer reviews of the central Texas salamander taxonomy from 11 scientific experts in this field. Because we considered the 4 recommended scientists to be qualified as independent experts, we included the 4 experts recommended by the commenter among the 11. Eight scientists responded to our request, and all eight scientists agreed with our recognition of four separate and distinct salamander species, as described in the
Species Information
section of the proposed and final listing rules. The commenter also provided an unpublished paper offering an alternative interpretation of the taxonomy of central Texas salamanders (Forstner 2012, entire), and that information was also provided to peer reviewers. We included two authors of the original species descriptions of the four central Texas salamander species to give them an opportunity to respond to criticisms of their work and so that we could fully understand the taxonomic questions about these species.

(46)
Comment:
One commenter requested a revision to the peer review plan to clarify whether it is a review of non-influential information or influential information.

Our Response:
We see no benefit from revising the peer review plan to clarify whether the review was of non-influential or influential information. The Service's “Information Quality Guidelines and Peer Review,” revised June 2012, defines influential information as information that we can reasonably determine the dissemination of which will have or does have a clear and substantial impact on important policy or private sector decisions. Also, we are authorized to define influential in ways appropriate for us, given the nature and multiplicity of issues for which we are responsible. As a general rule, we consider an impact clear and substantial when a specific piece of information is a principal basis for our position.

(47)
Comment:
One commenter requested clarification on what type of peer review was intended. Was it a panel review or individual review? Did peer reviewers operate in isolation to generate individual reports or did they work collaboratively to generate a single peer review document.

Our Response:
Peer reviews were requested individually. Each peer reviewer who responded generated independent comments.

(48)
Comment:
It does not seem appropriate to ask peer reviewers, who apparently do not have direct expertise on
Eurycea
or central Texas ecological systems, to provide advice on reasonableness of judgments made from generic statements or hyper-extrapolations from studies on other species. The peer review plan states that reviewers will have expertise in invertebrate ecology, conservation biology, or desert spring ecology. The disciplines of invertebrate ecology and desert spring ecology do not have any apparent relevance to the salamanders in question. The
Eurycea
are vertebrate species that spend nearly all of their life cycle underground. Central Texas is not a desert. The peer reviewers should have expertise in amphibian ecology and familiarity with how karst hydrogeology operates.

Our Response:
The peer review plan stated that we sought out peer reviewers with expertise in invertebrate ecology or desert spring ecology, but this was an error which was corrected in our correspondence with the peer reviewers. In the first comment period, we asked and received peer reviews from independent scientists with local and non-local expertise in amphibian ecology, amphibian taxonomy, and karst hydrology. In the second comment period, we sought out peer reviewers with local and non-local expertise in population ecology and watershed urbanization.

(49)
Comment:
The peer review plan appears to ask peer reviewers to consider only the scientific information reviewed by the Service. The plan should include the question of whether the scientific information reviewed constitutes the best available scientific and commercial data. The plan should be revised to clarify that the peer reviewers are not limited to the scientific information in the Service's administrative record.

Our Response:
The peer review plan states that we may ask peer reviewers to identify oversights and omissions of information as well as to consider the information reviewed by the Service. When we sent out letters to peer reviewers asking for their review, we specifically asked them to identify any oversights, omissions, and

inconsistencies with the information we presented in the proposed rule.

(50)
Comment:
The proposed peer review plan falls far short of the OMB Guidelines (2004 Office of Management and Budget promulgated its Final Information Quality Bulletin for Peer Review).

Our Response:
This commenter failed to tell us how the plan falls short of the OMB Guidelines. We adhered to the guidelines set forth for Federal agencies and in OMB's “Final Information Quality Bulletin for Peer Review,” released December 16, 2004, and the Service's “Information Quality Guidelines and Peer Review,” revised June 2012. While the draft peer review plan had some errors, we believe we satisfied the intent of the guidelines and that the errors did not affect the rigor of the actual peer review that occurred.

(51)
Comment:
One commenter stated that an additional peer review plan was not made available to the public for the second peer review.

Our Response:
We followed our peer review policy to prepare a peer review plan for our proposed rules, and we made the plan available for public review on our Web site. Both of our peer review processes followed this plan.

Salamander Populations

(52)
Comment:
A recent study by SWCA proposes that the COA's data are inadequate to assess salamander population trends and is not representative of environmental and population control factors (such as seasonal rainfall and drought). The study also states that there is very little evidence linking increased development to declining water quality.

Our Response:
We have reviewed the report by SWCA and COA's data and determined that it is reasonable to conclude that a link between increased urban development, declining water quality, and declining salamander populations exists for these species. Peer reviewers have also generally agreed with this assessment.

(53)
Comment:
The WCCF has been conducting research on salamanders of the Northern Edwards Aquifer since 2008. This included population monitoring at two Georgetown salamander sites and recently expanded to include water quality testing in both Georgetown salamander and Jollyville Plateau salamander ranges. Data indicate that populations are stable and healthy and water quality at Williamson County springs is excellent.

Our Response:
We acknowledge that two Georgetown salamander sites in Williamson County have been regularly monitored since 2008, and we have considered this data in the final listing rule. However, water quality testing by WCCF at salamander sites has only recently been initiated, and no conclusions regarding long-term trends in water quality at Georgetown salamander sites can be made. Furthermore, this salamander count dataset has not been conducted over a long enough time period to conclude that the salamander populations are stable and healthy at the two monitored sites.

(54)
Comment:
Specifically related to the Salado salamander, we note an apparent inconsistency in the proposed rule related to the locations of specific springs where the animal has been found. The section on impervious cover states, “The Salado salamander occurs within two watersheds (Buttermilk Creek and Mustang Creek).” In fact, to our knowledge the animal has been found in neither. The section discussing the specific springs identifies occurrences in springs in the Rumsey Creek and Salado Creek watersheds. The latter section appears to be correct.

Our Response:
Buttermilk Creek and Mustang Creek are the names of the 12-digit Hydrologic Unit Codes we used in our initial impervious cover analysis. They are larger watersheds that contain the smaller watersheds of Rumsey Creek and Salado Creek, which contain the springs occupied by the Salado salamander.

(55)
Comment:
The Service has no evidence that shows what the Georgetown salamander population is, or what a healthy average population would look like.

Our Response:
Although population data are lacking for most Georgetown salamander sites, population estimates of Georgetown salamanders have recently been completed at Twin Springs (118-216 adults) and Swinbank Spring (102-137 adults) (Pierce 2011a, p. 12). Part of what constitutes a healthy population is that threats have been removed or minimized. In terms of population size, it is unknown how many individuals are needed within a population to ensure its persistence over the long term.

(56)
Comment:
Given the central Texas climate and the general geology and hydrology of the Edwards Limestone formation north of the Colorado River, the description “surface-dwelling” or “surface residing” overstates the extent and frequency that the Georgetown and Salado salamanders utilize surface water. The phrase “surface dwelling population” in the proposed rule appears to be based on two undisclosed and questionable assumptions pertaining to Georgetown and Salado salamanders: (1) There are a sufficient number of these salamanders that have surface water available to them for sufficient periods of times so that the group could be called a “population”; and (2) there are surface-dwelling Jollyville Plateau salamander populations that are distinct from subsurface dwelling Jollyville Plateau salamander populations. Neither assumption can be correct unless the surface area is within a spring-fed impoundment that maintains water for a significant portion of a year.

Our Response:
In the proposed rule, we did not mean to imply or assume that “surface-dwelling populations” are restricted to surface habitat only. In fact, we made clear in the proposed rule that these populations need access to subsurface habitat. In addition, we also considered the morphology of these species in our description of their habitat use. The morphology of the Georgetown salamander and Salado salamanders serve as indicators of surface and subsurface habitat use. The Georgetown salamander surface populations have large, well-developed eyes. In addition, the Georgetown salamander has yellowish-orange tails, bright-red gills, and varying patterns of melanophores. The subterranean populations of the Georgetown salamander have reduced eyes and dullness of color, indicating adaptation to subsurface habitat. The Salado salamander has reduced eyes and lacks well-defined melanophores in comparison to other surface-dwelling
Eurycea.
However, they do possess developed eyes and some pigmentation, indicating some use of surface habitat.

(57)
Comment:
There may be uncertainty as to the number of Salado salamander populations, and how prolific the subsurface populations are. However, it is apparent that the species has historically been and currently is extremely difficult to observe and collect during low to average spring flows at the Salado Springs complex and more abundant and readily observable during above-average spring flows at the Salado Springs complex. The exception has been the spring outlets located in the Edwards outcrop upstream of the Salado Springs complex, where the salamander has been observed regularly during below-average spring flow. The consistency in observations from species surveys over the past 60 or more years is important: they do not reflect a trend downward in species population.

Our Response:
We agree that the available data on Salado salamander observations do not reflect a declining trend over time. However, these data are

also neither quantitative nor consistent enough to conclude that any Salado salamander population has been stable over time. The fact that Salado salamanders are rarely found at sites near the Village of Salado during periods of low flow suggests that this species is sensitive to threats such as drought and urbanization, as has been demonstrated for several closely related salamander species.

Threats

(58)
Comment:
The Service appears reluctant to distinguish between what are normal, baseline physical conditions (climate, geology, and hydrology) found in central Texas and those factors outside of the norm that might actually threaten the survival of the salamander species. Cyclical droughts and regular flood events are part of the normal central Texas climate and have been for thousands of years. The Service appears very tentative about accepting the obvious adaptive behaviors of the salamanders to survive floods and droughts.

Our Response:
The final listing rule acknowledges that drought conditions are common to the region, and the ability to retreat underground may be an evolutionary adaptation to such natural conditions (Bendik 2011a, pp. 31-32). However, it is important to note that although salamanders may survive a drought by retreating underground, this does not necessarily mean they are resilient to future worsening drought conditions in combination with other environmental stressors. For example, climate change, groundwater pumping, decreased water infiltration to the aquifer, potential increases in saline water encroachments in the aquifer, and increased competition for spaces and resources underground all may negatively affect their habitat (COA 2006, pp. 46-47; TPWD 2011, pp. 4-5; Bendik 2011a, p. 31; Miller
et al.
2007; p. 74; Schueler 1991, p. 114). These factors may exacerbate drought conditions to the point where salamanders cannot survive. In addition, we recognize threats to surface habitat at a given site may not extirpate populations of these salamander species in the short term, but this type of habitat degradation may severely limit population growth and increase a population's overall risk of extirpation from cumulative impacts of other stressors occurring in the surface watershed of a spring.

(59)
Comment:
There is no proof that Salado salamanders surfacing from the aquifer after spending lengthy periods subsurface are emaciated, or otherwise in a weakened state, or that they were unable to reproduce.

Our Response:
No studies have examined the biological effects of drought on Salado salamanders. However, a study on the closely related Jollyville Plateau salamander has documented decreases in body length following periods of drought (Bendik and Gluesenkamp 2013, pp. 3-4). In the absence of species-specific information, we conclude that the Salado salamander responds to drought in a similar way.

(60)
Comment:
In the proposed rule, the Service states that “Central Texas salamanders are particularly vulnerable to contaminants, because they have evolved under very stable environmental conditions.” The cycle of droughts and pulse rain events is certainly not a stable environmental condition. Drought is a stressor on all life forms in central Texas and necessitates species adaptability to survive.

Our Response:
This statement in the proposed rule refers to the presence of contaminants in the salamanders' habitat, not the occurrence of drought. Contaminants are a relatively new stressor for these species that has been introduced by human activity.

(61)
Comment:
The watershed recharging the Salado salamander occupied springs is largely undeveloped and little urbanization is occurring. There is no evidence that rapid urbanization is likely to occur in the foreseeable future in these watersheds due to lack of infrastructure. The population estimates in the proposed rule are based on countywide figures for Bell and Williamson Counties. Countywide figures grossly overstate the amount of population growth occurring in these specific watersheds. This can be confirmed by a review of census tracts data. Likewise, a significant portion of northwestern Williamson County outside of the jurisdiction of the main cities is undeveloped and lacking in available utilities to support dense development.

Our Response:
The proposed rule cites projected population growth and expected increases in demand for residential development, groundwater pumping, infrastructure, and other municipal services as a threat to the species throughout the Edwards Aquifer, including areas of Williamson and Bell Counties in the Northern Segment of the Aquifer. The estimates of growth came from multiple sources, including the Texas Water Development Board, the U.S. Census Bureau, and the Texas State Data Center. We are not aware of census tract data that project future populations at a scale lower than the county level. We maintain our conclusion that the Georgetown and Salado salamanders warrant listing partly due to projected human growth throughout their range.

(62)
Comment:
The average annual low flow of the Salado Springs complex was approximately 4.6 cubic feet per second (cfs), which occurred during the extreme drought in the mid-1950s. The low-end annual average range of spring flows from late 2011 to date exceeds and is nearly double that of the 4.6 cfs benchmark, even though the south central Texas region has been experiencing one of the worst droughts in recorded history. Clearwater Underground Water Conservation District's (CUWCD) records reflect that pumping from the Edwards aquifer within Bell County during the summer months actually decreased from 2011 to 2012 to 2013, which we believe is attributable to implementation of the drought management program. Thus, it is apparent that drought conditions, rather than some human agency, are responsible for low spring flows and that, possibly, groundwater district regulation of pumping could be having a positive effect on flows during the 2011 to 2013 drought conditions.

Our Response:
We acknowledge that drought has likely influenced spring flow for Salado salamander habitat more than groundwater pumping. Under Factor D of the final listing rule, we also acknowledge the water quantity protections afforded to Salado salamander habitat by the CUWCD. However, even under these protections, springs occupied by Salado salamanders are known to go dry for periods of time. The Service recognizes the desired future condition adopted by the CUWCD as a valuable tool for protecting groundwater; however, it is not adequate to ensure spring flow at all sites occupied by the Salado salamander.

(63)
Comment:
In regards to the Salado salamander, threats under Factor A are excessively vague and rest on certain assumptions which are clearly false. The Salado salamander has been found in springs in several locations and likely exists at others and the proposed designation of critical habitat treats every location where
Eurycea
has been identified the same. In fact, while the hydrogeologic context is generally consistent across the region, specific structural features may vary widely from one location to the next, so protective measures appropriate for one location may not be appropriate elsewhere. We can divide the springs into two basic types: (1) The Village of Salado springs, which represent the

ultimate outflow from the system as a whole, and (2) numerous lesser springs occurring at various locations up in the recharge (outcrop) zone. In either case, the springs are found in areas where extensive, structural disturbance is unlikely and where no identifiable threats related to possible changes in land use are anticipated at this time.

Because the major spring flows are moving through confined segments, bounded on their upper limit by an impervious unit, they are effectively insulated and protected from infiltration in the near vicinity of the springs. This is supported by the discussion of water temperature presented in the recently released TPWD report, A Biological and Hydrological Assessment of the Salado Springs Complex, Bell County, Texas, August 2012. Normal human activities, including typical construction, in near proximity to the springs, present little threat to the aquifer or the outflow from it. Further, the surrounding area has been fully developed for over 150 years. The lesser springs up in the recharge zone enjoy certain protections as well. Without exception, these are located in undeveloped settings that may be described as pristine. Specifically, the springs where the Salado salamander has been found are on a single, award-winning ranch, which constitutes one of the largest single land holdings in Bell County. The owners of this property have been widely recognized for their committed stewardship of the land. The ranch is operated under a management model that emphasizes low-impact grazing and recreational hunting. Habitat preservation and improvement are central components in this management model.

Our Response:
While it is possible that Salado salamanders exist at other unknown spring locations, our evaluation of the status of the species is limited to sites known to be occupied by the species at the time of the proposed listing. We agree that many site-specific variables affect both the degree of threat and potential for habitat modification at springs occupied by Salado salamanders, including land ownership, land uses in the immediate watershed, land uses in recharge areas, spring flow, level of recreation and physical disturbance, water quality, and other factors. Although we recognize the level of threat will vary across the range of the species, and recognize the strong stewardship of many landowners, we conclude that Factor A is neither vague nor based on false assumptions due to documented modifications to habitat within the very restricted range of the Salado salamander. Although construction near spring outlets may have relatively little impact on the entire aquifer, this type of development may likely have large impacts on the surface habitat of the spring. The springs within the Village of Salado have had heavy modification of the surface habitat, as described under Factor A of the proposed rule. Despite numerous field surveys over the last decade, Salado salamanders in many springs near well-developed areas, such as Big Boiling Spring, are rarely found. We consider habitat modification a significant threat, both now and in the future, due to projected growth, current land use practices, threats to water quality and quantity, as well as historical and ongoing physical disturbance to spring habitat.

(64)
Comment:
Through measuring water-borne stress hormones, researchers found that salamanders from urban sites had significantly higher corticosterone stress hormone levels than salamanders from rural sites. This finding serves as evidence that chronic stress can occur as development encroaches upon these spring habitats.

Our Response:
We are aware that researchers are pursuing this relatively new approach to evaluate salamander health based on differences in stress hormones between salamanders from urban and non-urban sites. Stress levels that are elevated due to natural or unnatural (that is, anthropogenic) environmental stressors can affect an organism's ability to meet its life-history requirements, including adequate foraging, predator avoidance, and reproductive success. We encourage continued development of this and other non-lethal scientific methods to improve our understanding of salamander health and habitat quality.

(65)
Comment:
Information in the proposed rule does not discern whether water quality degradation is due to development or natural variation in flood and rainfall events. Fundamental differences in surface counts of salamanders between sites are due to a natural dynamic of an extended period of above-average rainfall followed by recent drought.

Our Response:
We recognize that aquatic-dependent organisms such as the Georgetown and Salado salamanders will respond to local weather conditions; however, the best available science indicates that rainfall alone does not explain lower salamander densities at urban sites monitored by the COA. Furthermore, there is scientific consensus among numerous studies on the impacts of urbanization that conclude species diversity and abundance consistently declines with increasing levels of development, as described under Factor A in the final listing rule.

(66)
Comment:
Studies carried out by the Williamson County Conservation Foundation (WCCF) do not support the Service's assertions that habitat for the salamanders is threatened by declining water quality and quantity. New information from water quality studies performed at nine Georgetown and Jollyville Plateau salamander sites indicate that aquifer water is remarkably clean and that water quality protection standards already in place throughout the county are working.

Our Response:
The listing process requires the Service to consider both ongoing and future threats to the species. Williamson County has yet to experience the same level of population growth as Travis County, but is projected to have continued rapid growth in the future. Therefore, it is not surprising that some areas of Williamson County may exhibit good water quality, because threats to the Georgetown salamander or its habitat are primarily from future development. However, our peer reviewers concluded that the water quality data referenced by the commenter is not enough evidence to conclude that water quality at salamander sites in Williamson County is sufficient (see Comment 19 above). To fully assess the status of salamander populations and water quality requires long-term monitoring data. The water samples collected by the WCCF were comprised of a single sample event consisting of grab samples, so they offer limited insight into long-term trends in water quality (see Comment 19 above). The best available science indicates that water quality and species diversity consistently declines with increasing levels of urban development.

Hydrology

(67)
Comment:
The Service homogenizes ecosystem characteristics across the Austin blind, Georgetown, Jollyville Plateau, and Salado salamanders. The proposed rule often assumes that the “surface habitat” characteristics of the Barton Springs salamander and Austin blind salamander (year-round surface water in manmade impoundments) apply to the Salado, Jollyville Plateau, and Georgetown salamanders, which live in very different geologic and hydrologic habitat. The Georgetown and Salado salamanders live in water contained within a “perched” zone of the Edwards Limestone formation that is relatively thin and does not retain or recharge much water when compared to the Barton Springs segment of the Edwards Aquifer. Many of the springs where the

Georgetown and Salado salamanders are found are more ephemeral due to the relatively small drainage basins and relatively quick discharge of surplus groundwater after a rainfall event. Surface water at several of the proposed creek headwater critical habitat units is generally short lived following a rain event. The persistence of Jollyville Plateau, Georgetown, and Salado salamanders at these headwater locations demonstrates that the species are not as dependent on surface water as occupied impoundments suggest.

Our Response:
The Service recognizes that the Austin blind salamander is more subterranean than the other three species of salamander. However, the Georgetown, Jollyville Plateau, and Salado salamanders all spend large portions of their lives in subterranean habitat. Further, the Jollyville Plateau and Georgetown salamanders have cave-associated forms. There are numerous similarities among all four of these species. On page 50770 of the proposed rule, the similarities of these four salamander species are specified. They are all within the same genus, entirely aquatic throughout each portion of their life cycles, respire through gills, inhabit water of high quality with a narrow range of conditions, depend on water from the Edwards Aquifer, and have similar predators. The Barton Springs salamander shares these same similarities. Based on this information, the Service has determined that these species are suitable surrogates for each other.

Exactly how much these species depend on surface water is unclear, but the best available information suggests that the productivity of surface habitat is important for individual growth. For example, a recent study showed that Jollyville Plateau salamanders had negative growth in body length and tail width while using subsurface habitat during a drought and that growth did not become positive until surface flow returned (Bendik and Gluesenkamp 2012, pp. 3-4). In addition, the morphological variation found in these salamander populations may provide insight into how much time is spent in subsurface habitat compared to surface habitat.

(68)
Comment:
Another commenter stated that salamander use of surface habitat is entirely dependent on rainfall events large enough to generate sufficient spring and stream flow. Even after large rainfall events, stream flow decreases quickly and dissipates within days. As a result, the salamanders are predominately underground species because groundwater is far more abundant and sustainable.

Our Response:
See our response to previous comment above.

(69)
Comment:
Several commenters stated that there is insufficient data on long-term flow patterns of the springs and creek and on the correlation of flow, water quality, habitat, ecology, and community response to make a listing determination. Commenters propose that additional studies be conducted to evaluate hydrology and surface recharge area, and water quality.

Our Response:
We agree that there is a need for more study on the hydrology of salamander sites, but there are sufficient available data on the threats to these species to make a listing determination. We make our listing determinations based on the five listing factors, singly or in combination, as described in section 4(a)(1) of the Act. In making our listing determination, we considered and evaluated the best available scientific and commercial informa

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2014-03717. Public record. Not legal advice.