# Endangered and Threatened Wildlife and Plants; Final Designation of Critical Habitat for the Arroyo Toad

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## Record

- **Collection:** Federal Register
- **Document type:** Rule
- **Published:** February 7, 2001
- **Citation:** 66 FR 9414

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018—AG15
Endangered and Threatened Wildlife and Plants; Final Designation of Critical Habitat for the Arroyo Toad

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Final rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), designate critical habitat for the arroyo toad (
Bufo californicus
) pursuant to the Endangered Species Act of 1973, as amended (Act). A total of approximately 73,780 hectares (182,360 acres) in Monterey, Santa Barbara, Ventura, Los Angeles, San Bernardino, Riverside, Orange, and San Diego Counties, California, is designated as critical habitat.

Critical habitat identifies specific areas that are essential to the conservation of a listed species and, with respect to areas within the geographic range occupied by the species, that may require special management considerations or protection. The primary constituent elements for the arroyo toad are those habitat components that are essential for the primary biological needs of foraging, breeding, growth of larvae (tadpoles) and juveniles, intra-specific communication, dispersal, migration, genetic exchange, and sheltering. All areas designated as critical habitat for the arroyo toad contain one or more of the primary constituent elements.

We have not designated critical habitat on lands covered by an existing, legally operative, incidental take permit for the arroyo toad under section 10(a)(1)(B) of the Act, except for one area that has activities not covered by the habitat conservation plan (HCP). Subsection 4(b)(2) of the Act allows us to exclude from critical habitat designation areas where the benefits of exclusion outweigh the benefits of designation, provided the exclusion will not result in the extinction of the species. We believe that the benefits of excluding HCPs from the critical habitat designation for the arroyo toad will outweigh the benefits of including them.

In areas where HCPs have not yet had permits issued, we have designated critical habitat for lands essential to the survival and conservation of arroyo toads and that may require special management considerations or protections.

Section 4 of the Act requires us to consider economic and other relevant impacts of specifying any particular area as critical habitat. Section 7 of the Act prohibits destruction or adverse modification of critical habitat by any activity funded, authorized, or carried out by any Federal agency. We solicited data and comments from the public on all aspects of the proposal, including data on the economic and other impacts of designation and our approaches for handling HCPs. We revised the proposal to incorporate or address new information received during the comment periods.

We also correct the list of endangered species to account for a change in the taxonomy of the arroyo toad.

DATE:

This rule becomes effective on March 9, 2001.

FOR FURTHER INFORMATION CONTACT:

For information about Monterey, San Luis Obispo, Santa Barbara, and Ventura Counties, northern Los Angeles County and the desert portion of San Bernardino County, contact Diane Noda, Field Supervisor, Ventura Fish and Wildlife Office, 2394 Portola Road, Suite B, Ventura, California, (telephone 805/644-1766; facsimile 805/644-3958). For information about southern Los Angeles and urban and montane San Bernardino Counties, and Riverside, Orange, and San Diego Counties, contact Ken Berg, Field Supervisor, Carlsbad Fish and Wildlife Office, 2730 Loker Avenue West, Carlsbad, California 92008 (telephone 760/431-9440; facsimile 760/431-9624).

SUPPLEMENTARY INFORMATION:

Background

The following discussion is adapted from the final recovery plan for the arroyo toad (Service 1999), which is available from the addresses above. The arroyo toad
(Bufo californicus)
is one of three members of the southwestern toad
(B. microscaphus)
complex, in the family of true toads, Bufonidae. At the time it was listed, the arroyo toad was considered a subspecies of the southwestern toad,
B. microscaphus californicus.
The taxonomy of the complex has been examined recently by Gergus (1998). Based on his genetic studies, the arroyo toad should be considered a separate species,
Bufo californicus.

The arroyo toad is a small (adults: snout-urostyle (body) length 55 to 82 millimeters (mm) (2.2 to 3.2 inches (in.)), dark-spotted toad of the family Bufonidae, with females larger than males. Adult arroyo toads have a light-olive green or gray to tan dorsum (back) with dark spots and warty skin. The venter (underside) is white or buff and without dark blotches or spots. A light-colored, V-shaped stripe crosses the head and eyelids, and the anterior portion of the oval parotoid glands (just behind the eyes) are pale. There is usually a light area on each side of the sacral (pelvic) hump and in the middle of the back. The arroyo toad generally does not have a middorsal stripe, but if one is present, it extends only partway along the back.

The arroyo toad is found in coastal and desert drainages from Monterey County, California, south into northwestern Baja California, Mexico. These systems are inherently quite dynamic, with marked seasonal and annual fluctuations in climatic regimes, particularly rainfall. Natural climatic variations as well as other random events, such as fires and floods, coupled with the species' specialized habitat requirements, lead to annual fluctuations in arroyo toad populations. Human alterations of habitat can have unpredictable effects on arroyo toad populations. As a result of agriculture and urbanization, and the construction, operation, and maintenance of water storage reservoirs, flood control structures, roads, and recreational facilities such as campgrounds and off-highway vehicle parks, many arroyo toad populations have been reduced in size or extirpated (eliminated) due to extensive habitat loss from the 1920s into the 1990s. Jennings and Hayes (1994) believe that the loss of habitat, coupled with habitat modifications due to the manipulation of water levels in many central and southern California streams and rivers, as well as predation from introduced aquatic species and habitat degradation from introduced plant species, caused arroyo toads to be extirpated from 76 percent of the previously occupied habitat in California.

Because the arroyo toad was often confused with the California toad
(Bufo boreas halophilus),
which is very common in the same region, detailed studies of the natural history of the arroyo toad were not begun until the 1980s and 1990s. The arroyo toad exhibits breeding habitat specialization that favors shallow pools and open sand and gravel channels along low-gradient reaches of medium to large-sized streams (Service 1999). These streams can have either intermittent or perennial streamflow and typically experience periodic flooding that scours vegetation and replenishes fine sediments. In at least some portions of its range, the species also breeds in smaller streams and canyons where low-gradient breeding sites are more sporadically

distributed. Populations in smaller drainages are likely to be smaller and at greater risk of extirpation than those on larger streams and in larger habitat patches (Service 1999).

Arroyo toads also require and spend most of their adult life in upland habitats. Individual toads have been observed as far as 2 kilometers (km) (1.2 miles (mi)) from the streams where they breed, but are most commonly found within 0.5 km (0.3 mi) of those streams (Service 1999; Griffin
et al.
1999; Dan C. Holland, Camp Pendleton Amphibian and Reptile Survey, Fallbrook, California, unpublished data; Holland and Sisk 2000). Arroyo toads typically burrow underground during periods of inactivity and thus tend to utilize upland habitats that have sandy, friable (readily crumbled) soils. Although the upland habitat use patterns of this species are poorly understood, activity probably is concentrated in the alluvial flats (areas created when sediments from the stream are deposited) and sandy terraces found in valley bottoms of currently active drainages (Service 1999, Griffin
et al
. 1999, Sweet
in litt
. 1999, Ramirez 2000, Holland and Sisk 2000).

Habitat Characteristics and Ecological Considerations

Appropriate habitat for the arroyo toad is created and maintained by the fluctuating hydrological, geological, and ecological processes operating in riparian ecosystems and the adjacent uplands. The riparian/wash habitats as well as adjacent upland habitats are essential for this species' survival. Periodic flooding that modifies stream channels, redistributes channel sediments and alters pool location and form, coupled with upper terrace stabilization by vegetation, is required to keep a stream segment suitable for all life stages of the arroyo toad.

Specifically, arroyo toads require shallow, slow-moving streams, and riparian (areas near a source of water) habitats that are disturbed naturally on a regular basis, primarily by flooding. Periodic flooding helps maintain areas of open, sparsely vegetated sandy stream channels and terraces. Throughout their range, arroyo toads are typically found in medium- to large-sized streams, in stretches where riverbed gradients are low, there are adjacent alluvial terraces, and surface waters form shallow pools that persist at least through the early summer months (
e.g.
, into June). These habitat conditions are most prevalent in foothill valleys, but also occur in several drainages along the coastal plain and on the desert side of the Transverse Ranges.

Arroyo toads have specialized requirements for breeding habitats. Breeding, arroyo toads use open sites such as overflow pools, old flood channels, and shallow pools along streams. Such habitats rarely have closed canopies over the lower banks of the stream channel due to regular flood events. Heavily shaded pools are generally unsuitable for larval and juvenile arroyo toads because of lower water and soil temperatures and poor algal mat development. Episodic (temporary) flooding is critical to keep the low stream terraces relatively vegetation-free and the soils friable enough for juvenile and adult toads to create burrows. Pools less than 30 centimeters (cm) (12 in.) deep with clear water, flow rates less than 5 cm per second (0.2 foot (ft) per second), and bottoms composed of sand or well-sorted fine gravel are favored by adults for breeding.

Areas that are used by juveniles consist primarily of sand or fine gravel bars with varying amounts of large gravel or cobble with adjacent stable sandy terraces and streamside flats. Areas that are damp and have less than 10 percent vegetation cover provide the best conditions for juvenile survival and rapid growth (Service 1999).

The adjacent alluvial terraces used by subadults and adults for foraging and burrowing are typically sparsely to moderately vegetated with brush and trees such as mulefat (
Baccharis
spp.), California sycamore
(Platanus racemosa),
cottonwoods (
Populus
spp.), coast live oak (
Quercus agrifolia
), and willow (
Salix
spp.). The understory of stream terraces may consist of scattered short grasses, herbs, and leaf litter, with patches of bare or disturbed soil, or have no vegetation at all. Substantial areas of fine sand, into which adult toads burrow, must be present, but can be interspersed with gravel or cobble deposits.

Upland habitats used by arroyo toads during both the breeding and nonbreeding seasons include alluvial scrub, coastal sage scrub, chaparral (shrubby plants adapted to dry summers and moist winters), grassland, and oak woodland. Arroyo toads also have been found in agricultural fields (Griffin
et al.
1999), which probably constitute sinks (areas where mortality rates are higher than reproduction rates) over the long term, due to tilling, pesticide and fertilizer applications, and heavy equipment use (Paul C. Griffin, University of Montana, Missoula, Montana
in litt.
2000). When foraging, subadult and adult arroyo toads often are found around the driplines of oak trees. These areas often lack vegetation, yet have appropriate levels of prey. When active at night, toads often can be observed near ant trails feeding on passing ants, beetles, and other prey.

Males call from the streams during the breeding period, which is generally from late February to early July, although it can be extended in some years, depending on weather conditions. Males may remain at or near the breeding pools for several weeks and are particularly susceptible to predation at this time. Females apparently move to the breeding pools in the streams for only short time periods, in order to soak in the water and to breed (Griffin
et al.
1999; Nancy Sandburg, Santa Barbara, California, pers. comm. 1999). Amplexus (mating embrace of the female by the male) and egg-laying generally occur at the site where the male was calling. Female arroyo toads apparently release their entire clutch of 2,000 to 10,000 eggs as a single breeding effort and probably are unable to produce a second clutch during the mating season. If conditions are unsuitable, females may not obtain sufficient food for egg production and will forgo breeding during that year. The eggs are laid on substrates of sand, gravel, or cobble generally located away from vegetation in the shallow margins of the pool. High water flows can wash the eggs out of pools, breaking up the egg strands and killing the developing embryos. Silt eroding into the streams from road crossings, adjacent roads, overgrazing, or mining activities can cover and suffocate eggs.

Larvae usually hatch in 4 to 6 days at water temperatures of 12 to 16 degrees Celsius (54 to 59 degrees Fahrenheit). Larvae may take 8 to 14 days to become free-swimming, depending on the water temperature. They are particularly susceptible to the effects of high water flows during this time period, and heavy rains or untimely releases of water from dams can kill thousands of tadpoles very quickly. The larval period for arroyo toads lasts about 65 to 85 days, depending on water temperatures. Metamorphosis may occur at any time between April and the beginning of September, depending on the time of breeding, weather, and water quality. Peak metamorphosis occurs from the end of June to mid-July in the northern part of the toad's range and from late April to mid-May in southern California, although it may be later, particularly at higher elevations. For several days before metamorphosis, arroyo toad larvae cease feeding and aggregate in shallow water along the edges of gravel or sand bars, often under or along stranded algal mats. The metamorphosing and newly

metamorphosed toads are extremely susceptible to predation, habitat disturbance, and activities in the streams during this period (Service 1999).

Juvenile arroyo toads remain in the saturated substrate at the edges of breeding pools for 1 to 3 weeks after metamorphosis. They are active during the day and can be exposed on the barren sand because they are too small to burrow into the substrate. During this period, many toads are lost due to predation unless they can find some cover, such as cobble, algal mats, or pieces of debris, under or beside which to hide. As the toads mature, they move further from the pools onto sand and gravel bars. Crushing of toads by humans and livestock can be a substantial source of mortality at this stage (Service 1999).

As the toads grow, they begin to dig shallow burrows in fine sand, and switch to a nocturnal (night-time) activity pattern, when they forage for ants and beetles. Suitable sandy habitat can be highly localized resulting in dense concentrations of juvenile toads. If the substrate is not friable enough, juvenile toads often disperse farther away from the breeding pool into nearby stands of woody riparian vegetation. Most toads will move into willows or other vegetation as they grow, and as the stream dries naturally. Thus, to provide optimal conditions for arroyo toad survival and recovery, it is necessary to maintain a patchwork of suitable habitats. This patchwork will be on several scales, with open stream pools and sand or gravel bars interspersed with patches of native vegetation.

Little is known of the seasonal and annual movements or physiological ecology of adults, but subadults and some adult males move along streams as much as 0.8 km (0.5 mi) and over 1.0 km (0.6 mi) in a few cases during a single breeding season (Griffin et al. 1999; Ramirez 2000). Dispersal movements along the stream channel may be over 8 km (5 mi), as evidenced by finding arroyo toads breeding along upper Piru Creek in 1999 and 2000 (U.S. Forest Service (Forest Service) 1999, Maeton Freel, Forest Service, pers. comm. 2000). The area had been surveyed numerous times in the past without finding the species (Sam Sweet, University of California, Santa Barbara, pers. comm. 1999, 2000).

The extent of arroyo toad movements away from the stream channel is influenced by rainfall amounts, availability of surface water, width of streamside terraces and floodplains, vegetative cover, and topography (Griffin
et al.
1999; Ramirez 2000). In San Diego County, Griffin
et al.
(1999) found that, for toads radiotracked for more than 10 days, 14 female adult arroyo toads moved an average maximum distance of 135 meters (m) (443 feet (ft)) and a maximum of more than 300 m (984 ft) perpendicularly from streams, while 46 males moved an average maximum of 73 m (240 ft) from the streams. Thirty-three males along coastal streams with broad floodplains moved an average maximum of 92 m (302 ft) from the streams, while 13 in a narrower canyon moved only 23 m (75 ft) from the streambed (Griffin
et al.
1999). Ramirez (2000) recorded a maximum distance from the stream of 37 m (121 ft) for 12 arroyo toads in one desert slope stream with a very narrow floodplain, and 200 m (656 ft) for an undisclosed number of toads in another desert slope system with a broader floodplain. Those distances probably underestimate the true range of movement distances due to the limited numbers and tracking season. The extent to which toads move away from streams may be partially regulated by climatic conditions; moderate stable temperatures and high humidity facilitate longer-distance movements into upland habitats (Service 1999). We do not have enough data to characterize fully overwintering activities and habitat use in all of the systems that arroyo toads inhabit.

Several land use activities may affect the hydrology of arroyo toad stream habitats and destroy or severely modify the dynamic nature of the riparian systems upon which arroyo toads depend for reproduction, development, and survival. Human activities that affect water quality influence the amount and timing of nonflood flows or frequency and intensity of floods, affect riparian plant communities, or alter sedimentation dynamics can reduce or eliminate the suitability of stream channels for arroyo toad breeding habitat. Degradation or loss of surrounding riparian and upland habitats reduces and eliminates foraging and overwintering habitat. The introduction of nonnative plant and animal species can reduce the quality of all habitats used by arroyo toads, lead to detrimental levels of competition and predation, or reduce the availability of toad food. Run-off from roads can decrease habitat quality for arroyo toads, and roads provide access for humans, domestic animals, and invasive species that can lead to additional habitat degradation.

The effects of such activities and factors may not become apparent until many years later when the habitat finally becomes sufficiently degraded that arroyo toads can no longer reproduce and survive. Combined with the normal climatic fluctuations in the arroyo toad's range, which can include consecutive years of extremely high or low rainfall, human impacts can cause temporary or permanent extirpations of toads from some areas. Human activities that may cause adverse impacts to arroyo toads include urbanization and agriculture within and adjacent to riparian habitats, the use of pesticides and herbicides within or adjacent to arroyo toad habitat, dam building and the resulting reservoirs, water flow manipulations, sand and gravel mining, suction dredge mining, road placement across and within stream terraces, livestock grazing, off-highway vehicle use of roads and stream channels, the placement of campgrounds and other recreational facilities in arroyo toad habitat (especially on stream terraces), and the use of stream channels and terraces for recreational activities.

Previous Federal Actions

We first included the arroyo southwestern toad as a Category 2 candidate species in the September 18, 1985, Notice of Review of Candidate Species (50 FR 37958). It was included under the same category in subsequent notices on January 6, 1989 (54 FR 554), and November 21, 1991 (56 FR 58804). We were petitioned to list the arroyo toad under the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531
et seq.
), on December 30, 1992, and we published a proposed rule on August 3, 1993 (58 FR 41231). The arroyo toad was listed as endangered on December 16, 1994 (59 FR 64859). The designation of critical habitat was determined to be not prudent due to threats of vandalism and collection. A draft recovery plan for the arroyo southwestern toad was made available for public comment on May 6, 1998 (63 FR 25062), and we published the final recovery plan in September 1999.

At the time of listing, we concluded that designation of critical habitat for the arroyo toad was not prudent due to threats of vandalism and collection and because such designation would not benefit the species. We were concerned that critical habitat designation would likely increase the degree of threat from vandalism, collection, or other human-induced impacts. We were aware of at least one instance of the apparent collection of a group of breeding males that had occurred during the listing process, following the publication of information regarding an ongoing scientific study. During the development of the final recovery plan, concern was raised about collecting

activities on some public lands (Service 1999). However, we have determined that instances of vandalism have not increased since the listing of the arroyo toad, and the threats to this species and its habitat from specific instances of collection and habitat destruction do not outweigh the broader educational, potential regulatory, and other possible benefits that designation of critical habitat would provide for this species. A designation of critical habitat can provide educational benefits by formally identifying those areas essential to the conservation of the species. These areas are also identified in the recovery plans as the focus of our recovery efforts for the arroyo toad.

On March 4, 1999, the Southwest Center for Biological Diversity (Center for Biological Diversity) and Christians Caring for Creation filed a lawsuit in the Northern District of California against the Service for failure to designate critical habitat for seven species including the arroyo southwestern toad (
Bufo microscaphus californicus
). On November 5, 1999, the district court dismissed the plaintiffs' lawsuit pursuant to a settlement agreement entered into by the parties. Under the settlement agreement, we agreed to submit a proposed determination of critical habitat for the arroyo toad by June 1, 2000, and to submit the final designation to the
Federal Register
by January 5, 2001. By further agreement with the plaintiffs, this final deadline was to extended to January 19, 2001, to allow us time to review and incorporate the comments received on the proposed designation and draft economic analysis.

On June 8, 2000, we published a proposed determination for the designation of critical habitat for the arroyo toad (65 FR 36512). A total of approximately 193,600 hectares (478,400 acres) was proposed as critical habitat for the arroyo toad in Monterey, San Luis Obispo, Santa Barbara, Ventura, Los Angeles, San Bernardino, Orange, Riverside, and San Diego Counties, California. The comment period was open until August 7, 2000. During this 60-day comment period we held two public hearings (Valencia on June 27 and Temecula on June 29, 2000). On November 9, 2000, we published a notice (65 FR 67334) announcing the reopening of the comment period and a notice of availability of the draft economic analysis on the proposed determination. The comment period was open an additional 30 days, until December 11, 2000.

Critical Habitat

Critical habitat is defined in section 3 of the Act as—(I) the specific areas within the geographic area occupied by a species, at the time it is listed in accordance with the Act, on which are found those physical or biological features (I) essential to the conservation of the species and (II) that may require special management considerations or protection; and (ii) specific areas outside the geographic area occupied by a species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. “Conservation” means the use of all methods and procedures that are necessary to bring an endangered or a threatened species to the point at which listing under the Act is no longer necessary.

Critical habitat receives protection under section 7 of the Act through the prohibition against destruction or adverse modification of critical habitat with regard to actions carried out, funded, or authorized by a Federal agency. Section 7 also requires consultation on Federal actions that are likely to result in the destruction or adverse modification of critical habitat. In our regulations at 50 CFR 402.02, we define destruction or adverse modification as “. . . the direct or indirect alteration that appreciably diminishes the value of critical habitat for both the survival and recovery of a listed species. Such alterations include, but are not limited to, alterations adversely modifying any of those physical or biological features that were the basis for determining the habitat to be critical.” Aside from the added protection that may be provided under section 7, the Act does not provide other forms of protection to lands designated as critical habitat. Because consultation under section 7 of the Act does not apply to activities on private or other non-Federal lands that do not involve a Federal nexus, critical habitat designation would not afford any additional protections under the Act against such activities.

To be included in a critical habitat designation, the habitat must first be “essential to the conservation of the species.” Critical habitat designations identify, to the extent known using the best scientific and commercial data available, habitat areas that provide essential life cycle needs of the species (
i.e.,
areas on which are found the primary constituent elements, as defined at 50 CFR 424.12(b)).

Section 4 requires that we designate critical habitat at the time of listing and based on what we know at the time of the designation. When we designate critical habitat at the time of listing or under short court-ordered deadlines, we will often not have sufficient information to identify all areas of critical habitat. We are required, nevertheless, to make a decision and thus, must base our designations on what, at the time of designation, we know to be critical habitat.

Within the geographic area occupied by the species, we will designate only areas currently known to be essential. Essential areas should already have the features and habitat characteristics that are necessary to sustain the species. We will not speculate about what areas might be found to be essential if better information became available, or what areas may become essential over time. If the information available at the time of designation does not show that an area provides essential life cycle needs of the species, then the area should not be included in the critical habitat designation. Within the geographic area occupied by the species, we will not designate areas that do not now have the primary constituent elements , as defined at 50 CFR 424.12(b), that provide essential life cycle needs of the species.

Our regulations state that, “The Secretary shall designate as critical habitat areas outside the geographic area presently occupied by the species only when a designation limited to its present range would be inadequate to ensure the conservation of the species.” (50 CFR 424.12(e)). Accordingly, when the best available scientific and commercial data do not demonstrate that the conservation needs of the species require designation of critical habitat outside of occupied areas, we will not designate critical habitat in areas outside the geographic area occupied by the species.

Our Policy on Information Standards Under the Endangered Species Act, published in the
Federal Register
on July 1, 1994 (Vol.59, p. 34271), provides criteria, establishes procedures, and provides guidance to ensure that decisions made by the Service represent the best scientific and commercial data available. It requires Service biologists, to the extent consistent with the Act and with the use of the best scientific and commercial data available, to use primary and original sources of information as the basis for recommendations to designate critical habitat. When determining which areas are critical habitat, a primary source of information should be the listing package for the species. Additional information may be obtained from a recovery plan, articles in peer-reviewed

journals, conservation plans developed by States and counties, scientific status surveys and studies, biological assessments, unpublished materials, and expert opinion or personal knowledge.

Habitat is often dynamic, and species may move from one area to another over time. Furthermore, we recognize that designation of critical habitat may not include all of the habitat areas that may eventually be determined to be necessary for the recovery of the species. For these reasons, all should understand that critical habitat designations do not signal that habitat outside the designation is unimportant or may not be required for recovery. Areas outside the critical habitat designation will continue to be subject to conservation actions that may be implemented under section 7(a)(1), and to the regulatory protections afforded by the section 7(a)(2) jeopardy standard and the section 9 take prohibition, as determined on the basis of the best available information at the time of the action. We specifically anticipate that federally funded or assisted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans, or other species conservation planning efforts if new information available to these planning efforts calls for a different outcome.

Methods

In determining areas that are essential to conserve the arroyo toad, we used the best scientific and commercial data available. We have reviewed the overall approach to the conservation of the arroyo toad undertaken by the local, state, Tribal, and Federal agencies operating within the species' range since its listing in 1994, and the identified steps necessary for recovery outlined in the final Recovery Plan for the Arroyo Southwestern Toad (Service 1999).

We have also reviewed available information that pertains to the habitat requirements of this species, including material received since completion of the recovery plan. The material included data in reports submitted during section 7 consultations and by biologists holding section 10(a)(1)(A) recovery permits; research published in peer-reviewed articles and presented in academic theses and agency reports; regional Geographic Information System (GIS) coverages; occupied and potential habitat maps developed by the Forest Service (Forest Service 2000); habitat evaluation models for the San Diego County Multiple Species Conservation Program (MSCP), the North San Diego County Multiple Habitat Conservation Program (MHCP), and the North County Subarea of the MSCP for Unincorporated San Diego County; and a predictive habitat suitability map for San Diego County (Barto 1999). Further, information provided in comments on the proposed designation and draft economic analysis were evaluated and taken into consideration in the development of this final designation.

Primary Constituent Elements

In accordance with section 3(5)(A)(i) of the Act and regulations at 50 CFR 424.12, in determining which areas to propose as critical habitat, we are required to base critical habitat determinations on the best scientific and commercial data available and to consider those physical and biological features (primary constituent elements) that are essential to the conservation of the species, and that may require special management considerations and protection. These include, but are not limited to: space for individual and population growth and for normal behavior; food, water, air, light, minerals, or other nutritional or physiological requirements; cover or shelter; sites for breeding, reproduction, rearing (or development) of offspring; and habitats that are protected from disturbance or are representative of the historic geographical and ecological distributions of a species.

The areas designated as critical habitat are designed to provide sufficient breeding and upland habitat to maintain self-sustaining populations and metapopulations of arroyo toads throughout its range, and provide of those habitat components essential for the conservation of the species. Due to the complex life history and dispersal capabilities of the toads, and the dynamic nature of the environment in which they are found, the critical habitat designations include a range of stream reaches and associated uplands. The critical habitat units are configured to provide for dispersal and migration corridors, as well as allowing room for population expansion.

The primary constituent elements of critical habitat for the arroyo toad include rivers or streams with a hydrologic regime that supplies sufficient flowing water of suitable quality and sufficient quantity and at the appropriate times to provide space, food, and cover needed to sustain eggs, tadpoles, metamorphosing juveniles, and adult breeding toads; low-gradient stream segments (typically less than 4 percent) with sandy or fine gravel substrates which support the formation of shallow pools and sparsely vegetated sand and gravel bars for breeding and rearing of tadpoles and juveniles; a natural flooding regime or one sufficiently corresponding to a natural regime that will periodically scour riparian vegetation, rework stream channels and terraces, and redistribute sands and sediments, such that adequate numbers and sizes of breeding pools and sufficient terrace habitats with appropriate vegetation are maintained; upland habitats (particularly alluvial streamside terraces and adjacent valley bottomlands that include areas of loose soil and dependable subsurface moisture where toads can burrow underground and avoid desiccation) of sufficient width and quality to provide foraging and living areas for subadult and adult arroyo toads; few or no nonnative species that prey upon or compete with arroyo toads, or degrade their habitat; stream channels and upland habitats where manmade barriers do not completely or substantially impede migration to overwintering sites, dispersal between populations, or recolonization of areas that contain suitable habitat; and habitats with limited human-related disturbance.

Arroyo toads are not distributed uniformly throughout the critical habitat units. Arroyo toad breeding habitat is patchily distributed along the stream courses, and the same is true of appropriate upland habitat. Some areas primarily provide for migration and dispersal between breeding and foraging habitats or allow for dispersal to additional breeding pools that will accommodate expanding populations. Habitat conditions within streams can change rapidly in response to streamflows and other factors, such as the development and shifting of sand and gravel bars, and creation and disappearance of pools. Terrace and upland habitats, although more stable than streambed and riparian habitats, may change as a result of rainfall, earthquakes, fires, and other natural events. These factors may cause the habitat suitability of given areas to vary over time, thus affecting the distribution of toads.

Criteria Used To Identify Critical Habitat

The final recovery plan (Service 1999) for the arroyo toad identified the specific recovery needs of the species and serves as a starting point for

identifying areas essential to the conservation of the toad. Those drainage basins identified in the final recovery plan as areas necessary to achieve arroyo toad recovery are generally reflected in this final critical habitat designation.

The recovery strategy for the arroyo toad focuses on providing sufficient breeding and upland habitat to maintain self-sustaining populations and metapopulations of arroyo toads across the historic range of the species in California. To recover the arroyo toad to the point where it can be downlisted or delisted, it is essential to preserve the species' genetic diversity as well as the variety of ecological environments in which it has persisted.

We are designating critical habitat on lands that are considered essential to the conservation of the arroyo toad. Using the recovery plan for guidance, we determined an area was essential if it had one or more of the following characteristics: (1) supports a substantial core population of arroyo toads; (2) supports at least a small toad population and possesses favorable habitat conditions for population expansion and persistence; (3) suitable habitat situated in a location that appears to be crucial for maintaining the viability of a larger metapopulation; (4) occupied habitat on the periphery of the arroyo toad's geographic range; and (5) occupied habitat in atypical or underrepresented ecological environments (e.g., high elevation or desert-edge populations). These areas have the primary constituent elements described above.

Areas supporting core populations or that have the potential to support large populations are essential because they represent the foundation for continued persistence of the species. Furthermore, some habitat areas that would not be considered essential if geographically isolated are in fact essential when situated in locations where they facilitate continued connectivity between surrounding populations or play a significant role in maintaining metapopulation viability (e.g., by providing additional areas of occupancy that provide resilience to periodic extirpations of adjacent habitat patches). Populations on the periphery of the species range or in atypical ecological environments are important for maintaining the genetic diversity of the species which could be essential to evolutionary adaptation to changing climatic and environmental conditions.

Arroyo toads are found in a variety of ecologically and geographically distinct areas. In order to preserve this diversity, the recovery plan identifies three recovery units—Northern, Southern, and Desert—that reflect distinct ecological and geographic regions within the range of the species. The recovery units as identified in the final recovery plan are provided for reference in Table 1.

Table 1.—Recovery Units for the Arroyo Toad

Northern Unit

San Antonio River, Monterey County

Sisquoc River and tributaries, Santa Barbara County

Upper Santa Ynez River Basin (Indian, Mono, Agua Caliente), Santa Barbara County

Sespe Creek, Ventura County

Piru Creek (Upper and Lower), Ventura and Los Angeles counties

Upper Santa Clara River Basin, Los Angeles County

Upper Los Angeles Basin: (Big Tujunga, tributaries, Arroyo Seco), Los Angeles County

Southern Unit

Santiago Creek, Orange County

San Jacinto River and Bautista Creek, Riverside County

San Juan basin and Trabuco Creeks, Orange and Riverside counties

San Mateo and San Onofre Creek basins, San Diego and Orange counties

Lower Santa Margarita basin (De Luz, Roblar, and Sandia Creeks), San Diego County

Upper Santa Margarita basin (Temecula Creek, Arroyo Seco), Riverside and San Diego Counties

Lower and Middle San Luis Rey basin (below Lake Henshaw), San Diego County

Upper San Luis Rey basin (above Lake Henshaw), San Diego County

Santa Ysabel Creek, San Diego County

San Diego basin (including San Vicente Creek), San Diego County

Sweetwater River basin (including Viejas, Peterson Creeks), San Diego County

Cottonwood Creek basin, San Diego County

Desert Unit

Little Rock Creek, Los Angeles County

Upper Mojave River basin (Mojave, Deep, Horsethief, Little Horsethief), San Bernardino County

Whitewater River basin, Riverside County

To identify and map areas essential to the conservation of the species, we used the characteristics of essential habitat described above, data on known arroyo toad locations, and criteria in the recovery plan for reclassification of the species. Spatial data on stream gradients were used to determine the extent of suitable breeding habitat in these areas. Stream reaches containing suitable breeding habitat are often patchily distributed and interspersed with higher gradient segments. These interspersed high-gradient segments were included in the mapped essential stream reaches because of their proximity to suitable breeding habitat and their importance in facilitating movement between breeding sites.

To delineate essential upland habitat areas, we used a GIS-based modeling procedure to identify alluvial terraces and valley bottomlands adjacent to the previously identified essential stream reaches. Lacking spatially explicit data on geomorphology, elevation above the stream channel was used as an indicator of the extent of alluvial habitat. After some experimentation, we determined

that areas up to 25 m (80 ft) in elevation above the stream channel were most likely to contain the primary constituent upland habitat elements that are essential to arroyo toads. In extremely flat areas we recognized that there is likely a distance from the stream channel beyond which arroyo toads seldom travel, so we truncated the upland habitat delineation at a distance of 1.5 km (0.9 mi) if the 25-m elevation limit had not yet been reached. This distance is based on reported observations of arroyo toads at least 1.2 km from the upland/riparian ecotone (Holland and Sisk 2000). As it turned out, the 25-m elevation limit was reached at distances less than 1.5 km from the mapped stream channel along more than 99 percent of the stream reaches, so the distance limit rarely was a factor.

This GIS-based modeling technique was effective at capturing alluvial areas associated with river valleys. Thus, the width of the upland component of critical habitat varies based on topography. The habitat widens in broad alluvial valleys and narrows in places where streams run through constricted canyons or between surrounding hills.

The boundaries of critical habitat in each drainage are mapped as contiguous blocks of 250-m-by-250 m cells that conform to a Universal Transverse Mercator (UTM) grid. We evaluated the effectiveness of this approach by overlaying known arroyo toad locations on these habitat boundaries and calculating the percent encompassed. More than 95 percent of all known locations fell within the critical habitat boundaries. However, the vast majority of known locations come from stream surveys done during the breeding season and thus are detections of toads in breeding habitat. To more rigorously evaluate the critical habitat model, we assessed its effectiveness at capturing documented toad locations from the one available study that focused specifically on surveying toads in upland habitats. Holland and Sisk (2000) established extensive pitfall trap arrays at discrete distances from two stream courses and operated these arrays at various periods throughout the year. They had 466 captures of arroyo toads, 35 (7.5 percent) of which were identified as being in upland areas. Those toads were captured at distances that ranged from 15 to 1,175 m from the upland-riparian ecotone (boundary) (Holland and Sisk 2000). For the two areas sampled in this study, our modeled critical habitat boundaries encompassed 88 percent of the pitfall trapping stations where arroyo toads were detected.

To identify critical habitat units, we first examined those lands under Federal jurisdiction. Those lands include areas managed by the Department of Defense (DOD), the Forest Service, the Bureau of Land Management (BLM), the Army Corps of Engineers (Army Corps), and the Service. We also considered the existing status of non-Federal and private lands in designating areas as critical habitat. Section 10(a)(1)(B) of the Act authorizes us to issue permits for the take of listed species incidental to otherwise lawful activities. An incidental take permit application must be supported by a habitat conservation plan (HCP) that identifies conservation measures that the permittee agrees to implement for the species to minimize and mitigate the impacts of the requested incidental take. With one exception, non-Federal public lands and private lands that are covered by an existing operative HCP and executed implementation agreement (IA) for arroyo toads under section 10(a)(1)(B) of the Act are not designated as critical habitat because the benefits of exclusion outweigh the benefits of inclusion as discussed in section 4(b)(2) of the Act.

We are including portions of the Soboba, Pala, Rincon, Capitan Grande, Viejas, and Sycuan Indian Reservations because they all contain areas of high-quality habitat within units that are essential to the conservation of arroyo toads. We have coordinated with the respective Tribes on this designation under the guidance of the President's memorandum of April 29, 1994, “Government-to-Government Relations with Native American Tribal Governments” (59 FR 22951), E.O. 13175, and 512 DM 2, which requires us to coordinate with federally recognized Tribes on a Government-to-Government basis.

In defining critical habitat boundaries, we made an effort to exclude all developed areas, such as towns, housing developments, and other lands unlikely to contain primary constituent elements essential for arroyo toad conservation. Our 250-meter UTM grid minimum mapping unit was designed to minimize the amount of development along the urban edge included in our designation. However, this minimum mapping unit does not exclude all developed areas, such as buildings, aqueducts, railroads, airports, and other lands unlikely to contain the primary constituent elements. Federal actions limited to these areas would not trigger a section 7 consultation, unless they affect the species and/or the primary constituent elements in adjacent critical habitat.

Critical Habitat Designation

The approximate area encompassing the designated critical habitat by county and land ownership is shown in Table 2.

Table 2.—Approximate Critical Habitat in Hectares (ha) (Acres (ac)) by County and Land Ownership
[Area estimates reflect critical habitat unit boundaries, not the primary constituent elements within]

County
Forest Service
BLM
FWS
Military
State/Local
Tribal
Private
Total

Monterey
0
0
0

2,900 ha
(7,170 ac)

0
0

20 ha
(50 ac)

2,920 ha
(7,220 ac)

Santa Barbara

3,415 ha
(8,440 ac)

0
0
0
0
0

2,365 ha
(5,830 ac)

5,780 ha
(14,270 ac)

Ventura

4,080 ha
(10,090 ac)

0
0
0
0
0

360 ha
(900 ac)

4,440 ha
(10,990 ac)

Los Angeles

4,505 ha
(11,130 ac)

10 ha
(30 ac)

0
0

20 ha
(45 ac)

0

3525 ha
(8705 ac)

8,060 ha
(19,910 ac)

San Bernardino

1,130 ha
(2,790 ac)

80 ha
(200 ac)

0

925 ha
(2,290 ac)

540 ha
(1,330 ac)

0

4,010 ha
(9,910 ac)

6,685 ha
(16,520 ac)

Riverside

970 ha
(2,400 ac)

620 ha
(1,530 ac)

0
0

90 ha
(220 ac)

155 ha
(390 ac)

4,360 ha
(10,785 ac)

6,195 ha
(15,325 ac)

Orange

325 ha
(815 ac)

0
0

30 ha
(75 ac)

1,090 ha
(2,700 ac)

0

3,375 ha
(8,330 ac)

4,820 ha
(11,920 ac)

San Diego

5,745 ha
(14,190 ac)

230 ha
(575 ac)

345 ha
(860 ac)

1,325 ha
(3,270 ac)

2380 ha
(5870 ac)

1,565 ha
(3,870 ac)

23,290 ha
(57,570 ac)

34,880 ha
(86,205 ac)

Total

20,170 ha
(49,855 ac)

940 ha
(2,335 ac)

345 ha
(860 ac)

5,180 ha
(12,805 ac)

4120 ha
(10,165 ac)

1,720 ha
(4,260 ac)

41,305 ha
(102,080 ac)

73,780 ha
(182,360 ac)

Critical habitat includes arroyo toad habitat throughout the species' range in the United States (
i.e.
, Monterey, Santa Barbara, Ventura, Los Angeles, Riverside, San Bernardino, Orange, and San Diego Counties, California). Lands designated are under private, local agency, county, State, Tribal, and Federal ownership. Lands designated as critical habitat have been divided into 22 Critical Habitat Units. A brief description of each unit, and reasons why they are essential for the conservation of the arroyo toad, are presented below. The units are generally based on geographically distinct river basins. In several instances, a river basin has been broken into two or more units based on human or natural landscape features that effectively separate portions of the basin (
e.g.
, a large reservoir or gorge). Based on observations recorded since 1985, each of these units is now occupied by arroyo toads.

Jennings and Hayes (1994) estimate that arroyo toads have lost 76 percent of their historic habitat. Although the linear measure of historically occupied streams may not be four times what is currently occupied, it is clear from museum records and data on extant populations that the habitats capable of supporting large numbers of arroyo toads have decreased dramatically in the last 100 years. The reaches that typically support or historically supported the highest densities of toads are those in the lower and middle portions of river basins, typically associated with third order or larger streams. Many of those reaches have been lost to or degraded by urban development, intensive agriculture, water diversions, sand and gravel mining operations, and reservoirs. For these reasons, we believe all of the areas we are designating may require special management considerations or protection.

Northern Recovery Unit

The following seven critical habitat units are located in the Northern Recovery Unit for the arroyo toad, as discussed in the final recovery plan. Most of the lands are Federally owned, and management needs are being addressed through the section 7 consultation process and the development of management plans and conservation strategies. Because the remaining toad populations have been reduced in size, and the habitat fragmented by road construction, dams, agriculture, and urbanization, it is essential to protect them to reduce further loss of genetic diversity and safeguard against the loss of any one population due to random natural or human-caused events.

Unit 1: San Antonio River, Monterey County

Unit 1 consists of the San Antonio River and adjacent uplands, from about 3 km (2 mi) upstream of the confluence with Mission Creek downstream to San Antonio Reservoir, a distance of about 27 km (17 mi), and includes portions of Mission Creek and other tributaries. The unit encompasses approximately 2,920 ha (7,220 ac), more than 99 percent of which is on the Fort Hunter Liggett Military Reservation. This is the northernmost known population of arroyo toads and is approximately 160 km (100 mi) north of the nearest documented extant population. The protection and recovery of this area are essential to maintain the complete genetic variability of the species and the full range of ecological settings within which it is found.

Unit 2: Sisquoc River, Santa Barbara County

Unit 2 consists of 44 km (27 mi) of the Sisquoc River and adjacent uplands, from Sycamore Campground downstream to just below the confluence with La Brea Creek. The unit encompasses approximately 3,385 ha (8,360 ac), of which 56 percent is private land and 43 percent is within the Los Padres National Forest. Upper stretches of the river are within the National Forest and mostly within the San Rafael Wilderness Area. Below the National Forest boundary, the river and adjacent uplands are on private lands. This long, unregulated stream is occupied arroyo toad habitat and is one of the few remaining major rivers in southern California with a natural flow regime. This area is essential to maintaining genetic diversity of the species. The protection of this population is essential as it is a core population. Arroyo toads from this population may be a suitable source for the reestablishment of populations outside critical habitat on the upper Salinas River, if appropriate habitat can be identified and protected.

Unit 3: Upper Santa Ynez River Basin, Santa Barbara County

Unit 3 is located upstream of Gibraltar Reservoir and incorporates portions of the upper Santa Ynez River, Indian Creek, Mono Creek, and adjacent uplands. The unit encompasses approximately 2,395 ha (5,910 ac) within the boundaries of Los Padres National Forest; 81 percent is on National Forest lands and 19 percent is on private inholdings. Designated portions of the upper Santa Ynez River extend 16 km (10 mi) from Jameson Reservoir downstream to Gibraltar Reservoir. Indian Creek is designated from the Buckthorn Creek confluence down to the Mono Debris Dam, a distance of 8 km (5 mi). Mono Creek and associated uplands are designated for 12 km (7.5 mi) from the first unnamed stream below The Narrows to its confluence with the Santa Ynez River. This area is essential to maintaining genetic diversity of the species. A substantial and well-studied arroyo toad population occurs in this area (Sweet 1992, 1993). It is likely the remnant of a much larger population that historically extended downstream below what is now Lake Cachuma and upstream into the area occupied by Jameson Reservoir. This area has favorable habitat conditions for population expansion and persistence; with the reduction of threats through management, this area should support a larger arroyo toad population.

Unit 4: Sespe Creek, Ventura County

Unit 4 includes 35 km (22 mi) of Sespe Creek and adjacent uplands, from the lower end of Sespe Gorge (elevation approximately 1,075 m (3,530 ft)) downstream to the confluence with Alder Creek. The unit encompasses approximately 2,340 ha (5,800 ac), of which 94 percent is on the Los Padres National Forest and the remainder is in private inholdings. A substantial arroyo toad population occurs in this unit (Service 1999) along an undammed stream in a watershed that is predominately National Forest land. This area is essential to maintaining genetic diversity of the species. It is a core population that can be expanded with appropriate management. In all likelihood, arroyo toad populations in units 4, 5, and 6 historically were part of a large Santa Clara River Basin metapopulation. Ecologically, these units provided a link between the more coastal populations on the Sisquoc and Santa Ynez rivers, and populations in the Desert Recovery Unit. Substantial barriers to toad movement now exist between these units, including dams, agriculture, and urban development.

Unit 5: Piru Creek, Ventura and Los Angeles counties

Unit 5 includes Piru Creek and adjacent uplands from the confluence with Lockwood Creek downstream to Pyramid Reservoir (Subunit 5a), and from Pyramid Dam downstream to Lake Piru (Subunit 5b). Subunit 5b also includes Agua Blanca Creek from Devil's Gateway downstream to the confluence with Piru Creek. The unit

encompasses approximately 2,975 ha (7,345 ac), 92 percent of which is within the Los Padres and Angeles National Forests, with the remaining on private inholdings. A substantial arroyo toad population occurs in this unit (Service 1999), although much of the historical arroyo toad habitat in the area is now inundated by the two reservoirs, this population should expand and become more stable, with appropriate management. Protection and recovery of this population is essential to maintain the range of ecological settings from the coast to the desert.

Unit 6: Upper Santa Clara River Basin, Los Angeles County

Unit 6 includes portions of Castaic and San Francisquito Creeks and adjacent uplands. The unit encompasses approximately 3,360 ha (8,305 ac), of which 68 percent is private land and 30 percent is within the Angeles National Forest. Subunit 6a includes Castaic Creek from Bear Canyon downstream to Castaic Lake and Fish Creek from Cienaga Spring to the confluence with Castaic Creek. Subunit 6b includes Castaic Creek below Castaic Lake to the confluence with the Santa Clara River. Subunit 6c includes San Francisquito Creek from Bee Canyon to the southern end of section 34 in township 5 N, range 16 W. Arroyo toads are found on Castaic Creek both above and below the reservoir, and recent surveys have found evidence of the species on San Francisquito Creek. The arroyo toad population on Castaic has expanded in recent years with changes in management, and San Francisquito Creek offers an excellent opportunity for further expansion. With appropriate management of nonnative plants and animals and habitat rehabilitation, the stability of the Upper Santa Clara River basin arroyo toad population should increase substantially. The Santa Clara River, as managed under the Natural River Management Plan (Valencia Company 1998) and associated conservation easements, is essential because it serves as a dispersal corridor for arroyo toads between Castaic Creek and San Francisquito Creek. This is the easternmost population in the Northern Recovery Unit, and as such provides the final link in the range of ecological settings for this recovery unit.

Unit 7: Upper Los Angeles River Basin, Los Angeles County

Unit 7 includes portions of Big Tujunga, Mill, Alder, and Arroyo Seco creeks, and adjacent uplands. The unit encompasses approximately 3,225 ha (7,970 ac), of which 62 percent is within the Angeles National Forest and 38 percent is private land. Subunit 7a includes 19 km (11.8 mi) of Big Tujunga Creek from below Big Tujunga Dam downstream to Hansen Lake. Subunit 7b encompasses: (1) approximately 13 km (8 mi) of upper Big Tujunga Creek from immediately above Big Tujunga Reservoir upstream to 2 km (1.2 mi) above the confluence with Alder Creek, (2) almost 6 km (3.7 mi) of Mill Creek from the Monte Cristo Creek confluence downstream to Big Tujunga Creek, and (3) 3 km (1.9 mi) of Alder Creek from the Mule Fork confluence downstream to Big Tujunga Creek. Subunit 7c includes 9.5 km (6 mi) Arroyo Seco Creek from the Long Canyon confluence downstream to the upper end of Devil's Gate Reservoir.

Arroyo toads have recently been documented (in the last 5 years) in each of these drainages and, collectively, they represent the only significant known population remaining in the coastal foothills of the San Gabriel Mountains. This unit is essential primarily because it is occupied and contains favorable habitat conditions for major population increases, particularly if the timing of water releases from Big Tujunga Dam can be adjusted to restore the seasonal habitat conditions necessary for successful arroyo toad breeding. In addition, populations in Alder, Mill, and Arroyo Seco creeks extend into high-elevation environments that are atypical for the arroyo toad and may be important to maintaining genetic diversity.

Southern Recovery Unit

The following 12 critical habitat units are located in the Southern Recovery Unit for the arroyo toad, as discussed in the final recovery plan. Arroyo toads probably occurred in and along the coastal plain portions of all the streams in this unit, but are now found on the coastal plain only in units 8, 10, 11, and 12.

Unit 8: Santiago Creek, Orange County

Unit 8 is located just above Irvine Lake where Black Star, Baker, and Silverado creeks join Santiago Creek. The unit encompasses approximately 500 ha (1,235 ac), 99 percent of which is private land; the remainder is within the Cleveland National Forest. A 3 km (1.9 mi) stretch of Black Star Creek and associated uplands are designated from near the southwest corner of Section 30 (T4S, R7W) downstream to Santiago Creek. A 3.5 km (2.2 mi) stretch of lower Baker Canyon is also included, as is approximately 1 km of Santiago Creek. This unit is predominantly within the North Ranch Policy Plan Area within the Orange County Central-Coastal NCCP/HCP. As discussed in more detail below, there is not yet an approved Implementing Agreement or section 10 (a)(1)(B) permit for the take of arroyo toads in the North Ranch Policy Plan Area, so we are including it in this final critical habitat designation. As an artifact of the mapping unit size used to designate critical habitat for the arroyo toad within the North Ranch Policy Plan area, a small portion of the Orange County Central-Coastal NCCP/HCP where take of the arroyo toad has been authorized is within the boundaries of this critical habitat unit. However, due to the conservation assurances and take authorization provided for the arroyo toad in this portion of the critical habitat unit, we hereby exclude it from designation as critical habitat.

With the current status of arroyo toads in this unit is poorly known, they were observed in lower Baker Canyon in 1985 (Robert Fisher, USGS, pers. comm. 1999). Surveys performed along Santiago Creek in 1997 failed to detect arroyo toads (Harmsworth Associates 1998), and reportedly no arroyo toads were detected during year 2000 surveys of Irvine Company land within this unit (Adrian Wolf, pers. comm. 2000). However, high-quality habitat still exists in this area (e.g., Baker Canyon) that likely was not covered in recent survey efforts.

Unit 8 is considered essential because habitat conditions are favorable for population expansion and long-term persistence. Maintaining a population in this unit should also enhance the viability of the larger arroyo toad metapopulation that extends across the lower slopes of the Santa Ana Mountains from Santiago Creek to San Mateo Creek (crossing into Units 10 and 11). We think there are opportunities for movement of individuals between occupied drainages in this area, which would positively influence populations in each drainage.

Unit 9: San Jacinto River and Bautista Creek, Riverside County

Unit 9 includes portions of the San Jacinto River, Indian Creek, Bautista Creek, and adjacent uplands, east of the town of Hemet. The unit encompasses approximately 1,710 ha (4,220 ac), of which 60 percent is private land, 22 percent is within the San Bernardino National Forest, 9 percent is within the Soboba Indian Reservation, and the remaining 9 percent is on other Federal or State owned lands. Subunit 9a covers 11 km (6.8 mi) of the San Jacinto River from the Sand Canyon confluence downstream to just below the confluence with Indian Creek and also includes the lower 1 km (0.6 mi) of

Indian Creek. Subunit 9b covers 11 km (6.8 mi) of Bautista Creek from near the middle of section 20 (T6S, R2E) downstream to near the middle of section 27 (T5S, R1E), where the stream enters a debris basin. In the proposal, we stated that while the current status of arroyo toads in this unit is poorly known, there are historic records from the 1970s and high quality habitat still exists in the area. Surveys conducted in the summer of 2000 confirmed the existence of arroyo toad populations on Bautista Creek (Lisa Lyren, USGS,
in litt.
2000) and the San Jacinto River (Brock Ortega, Dudek & Associates, pers. comm. 2000) within the San Bernardino National Forest. These populations likely extend downstream onto private and tribal lands.

Approximately 155 ha (390 ac) of the Soboba Indian Reservation are included in this unit. High quality arroyo toad habitat exists within the reservation along lower Indian Creek to its confluence with the San Jacinto River. It is important to maintaining the integrity of the unit. Unit 9 is essential for arroyo toad conservation because it is occupied habitat with favorable conditions for population persistence in an area that is on the southeastern periphery of the species range. Decidedly isolated from other known populations, this is a substantial patch of suitable habitat which supports a population that is important for genetic diversity and has a high likelyhood of persistence.

Unit 10: San Juan and Trabuco Creeks, Orange and Riverside counties

Unit 10 includes portions of San Juan Creek, Bell Canyon, Trabuco Creek, and adjacent uplands. The unit encompasses approximately 3,745 ha (9,270 ac), of which 56 percent is private land, 29 percent is Orange County park land (Caspers Wilderness Park and O'Neill Regional Park), and 15 percent is on the Cleveland National Forest. Subunit 10a covers approximately 30 km (18.6 mi) of San Juan Creek from the bottom of Decker Canyon downstream to Interstate 5 and includes about 4 km (2.5 mi) of Bell Canyon from just below Crow Canyon downstream to the confluence with San Juan Creek. Subunit 10b covers approximately 8 km (5 mi) of Trabuco Creek from Falls Canyon downstream to the lower end of O'Neill County Park.

San Juan and Bell creeks are essential for conservation of the arroyo toad because they support a large core population, which is concentrated within Caspers Wilderness Park and private lands downstream (P. Bloom,
in litt.
). The designated stretch of Trabuco Creek is considered essential because it is currently occupied by arroyo toads (D. Holland, pers. comm.) and conditions there are favorable for population persistence. A population in this area should also help maintain connectivity between toads in Santiago Creek to the north and Bell Canyon to the south.

Unit 11: San Mateo Basin, San Diego and Orange counties

Unit 11 includes portions of San Mateo, Christianitos, Talega, Gabino, and La Paz creeks, and adjacent uplands. The unit encompasses approximately 1,820 ha (4,495 ac), of which 54 percent is within portions of the Camp Pendleton Marine Corps Base that are leased to outside parties for other land uses (i.e. San Onofre State Park and agricultural lands) and 43 percent is on private land. Portions of Camp Pendleton outside of the leased lands are excluded. Two disjunct sections of San Mateo Creek are included: Subunit 11b covers approximately 2 km (1.2 mi) within the Cleveland National Forest near Devils Canyon, and subunit 11a extends about 5 km (3.1 mi) from the Christianitos Creek confluence downstream to just below Interstate 5. Portions of Christianitos Creek are designated from just above Gabino Creek downstream to the confluence with San Mateo Creek. Approximately 5 km (3.1 mi) of Gabino Creek upstream from its confluence with Christianitos Creek are designated, including about 1 km (0.6 mi) of La Paz Creek. The unit also includes approximately 7 km (4.4 mi) of Talega Creek upstream from its confluence with Christianitos Creek and beyond the boundaries of Camp Pendleton.

San Mateo and Christianitos creeks support large core populations (Holland and Goodman 1998) and are essential to conservation of the species. An unusual and potentially important aspect of this unit is its close proximity to the coast. Historically, there were probably many near-coast populations, but few remain due to extensive urbanization and river channelization. Distinctive climatic conditions near the coast may provide different selective pressures on toads in this area, potentially favoring specific genetic characteristics.

Unit 12: Lower Santa Margarita River, San Diego County

Unit 12 includes approximately 20 km (12.4 mi) of the Santa Margarita River and adjacent uplands, from the lower end of Temecula Canyon to the boundary of Camp Pendleton (Subunit 12b) and almost 4 km of De Luz Creek from the town of De Luz to the boundary of Camp Pendleton (Subunit 12A). The unit encompasses approximately 1245 ha (3075 ac), of which 30 percent is within the Fallbrook Naval Weapons Station and 70 percent is on private land. Land within the Camp Pendleton Marine Corps Base is excluded from this unit (see Discussion in Exclusion Under Section 4(b)(2)).

Recent surveys of the Santa Margarita River and De Luz Creek immediately downstream of this unit have documented what is probably the largest known population of arroyo toads (Holland and Goodman 1998). Portions of these drainages within this unit are also occupied and considered essential because they supplement and adjoin the large population on Camp Pendleton and potentially provide connectivity to populations in the upper Santa Margarita River basin.

Unit 13: Upper Santa Margarita River Basin, Riverside and San Diego counties

Unit 13 is located above Vail Lake and includes portions of Temecula Creek, Wilson Creek, Arroyo Seco Creek, and adjacent uplands. The unit encompasses approximately 4,695 ha (11,610 ac), of which 89 percent is private land and 10 percent is within the Cleveland National Forest. Approximately 25 km (15.5 mi) of Temecula Creek are designated from Dodge Valley downstream to Vail Lake. The unit also includes 6 km (3.7 mi) of Wilson Creek from Lancaster Valley down to Vail Lake and 11 km (6.8 mi) of Arroyo Seco Creek from Crosley Homestead down to Vail Lake.

The broad, flat alluvial valleys found in this unit contain high-quality habitat for arroyo toads. The unit is essential because there are documented occurrences in Temecula, Wilson, and Arroyo Seco creeks, and habitat conditions are favorable for population expansion and long-term persistence.

Unit 14: Lower and Middle San Luis Rey River Basin, San Diego County

Unit 14 includes portions of the San Luis Rey River below Lake Henshaw and adjacent uplands, and includes sections of Pala and Keys creeks. The unit encompasses approximately 7,470 ha (18,455 ac), of which 79 percent is private land and 18 percent is Tribal land. Approximately 48 km (30 mi) of the San Luis Rey River are designated from the western edge of the La Jolla Indian Reservation downstream to the confluence with Guajome Creek near the city of Oceanside. It also includes approximately 5.5 km (3.4 mi) of Pala Creek and 2.7 km (1.7 mi) of Keys Creek

upstream from the confluence with the San Luis Rey River.

This long, low-elevation (all below 305 m (1,000 ft) in elevation) unit, situated in a broad, flat valley, is essential to arroyo toad conservation because it supports a large core population that, provided threat factors can be addressed, is capable of long-term persistence. Some of the best arroyo toad habitat in this unit occurs within the Pala and Rincon Indian Reservations.

The San Luis Rey River provides important high quality habitat for the arroyo toad. However, intensive urbanization and agriculture near the coast, and dams and water diversions in the upper end, have reduced habitat quality in the upper and lower portions of this unit. Approximately 18 percent of the identified remaining suitable habitat along the San Luis Rey is on Tribal land. The Pala and Rincon Reservations support broad alluvial floodplains that contain high quality habitat and recent surveys have documented a substantial arroyo toad concentration on both reservations. If habitats on these reservations are lost, the remaining population would be highly fragmented and vulnerable to extirpation.

Unit 15: Upper San Luis Rey Basin, San Diego County

Unit 15 includes the upper San Luis Rey River above Lake Henshaw, two of its headwater tributaries, and adjacent uplands. The unit encompasses approximately 4,525 ha (11,180 ac), of which 80 percent is private land and 20 percent is within the Cleveland National Forest. This unit consists of two subunits. Subunit 15a covers almost 14 km (8.7 mi) of the upper San Luis Rey River from the Indian Flats area downstream to the upper end of Lake Henshaw and includes about 12.5 km (7.8 mi) of Agua Caliente Creek from the western edge of section 13 (T10S, R3E) to the confluence with the San Luis Rey. Subunit 15b includes approximately 2.5 km (1.6 mi) of the West Fork of the San Luis Rey River where it runs through Barker Valley. Arroyo toads occur in each of these drainages, with the largest concentration found along Agua Caliente Creek.

This unit is essential because it contains a unique assemblage of several small, disjunct, high-elevation populations and one large, core population (on Agua Caliente Creek) in an area where in-stream and/or overland dispersal between populations is probably still possible.

Unit 16: Santa Ysabel Creek, San Diego County

Unit 16 includes portions of Santa Ysabel Creek and adjacent uplands, and includes portions of Santa Maria Creek, Guejito Creek, and Temescal Creek (Pamo Valley). The unit encompasses approximately 4,670 ha (11,545 ac), of which 87 percent is private land and 11 percent is within the Cleveland National Forest. The unit consists of three subunits. Subunit 16a includes approximately 13 km (8 mi) of Santa Ysabel Creek and adjacent uplands from Sutherland Reservoir downstream to the western boundary of the Cleveland National Forest near Boden Canyon (which is the eastern boundary of the San Diego MSCP area). Subunit 16a also includes approximately 7 km (4.3 mi) of Temescal Creek from the northern edge of Pamo Valley to the confluence with Santa Ysabel Creek. Subunit 16b includes approximately 12 km (7.5 mi) of Guejito Creek from the 610 m (2,000 ft) elevation contour downstream to the San Diego MSCP boundary near San Pasqual Valley. Subunit 16c covers approximately 10 km (6 mi) of Santa Maria Creek from the west side of Ramona to the San Diego MSCP boundary near San Pasqual Valley.

All of the drainages included in this unit are occupied by arroyo toads, and a large population exists along Temescal and Santa Ysabel creeks within Pamo Valley. This unit is essential to arroyo toad conservation because it supports a large core population and contains several additional populations that can remain viable and interconnected. This unit also provides an important linkage and genetic interchange with a core arroyo toad population in San Pasqual Valley, within the San Diego MSCP area.

Unit 17: San Diego River/San Vicente Creek, San Diego County

Unit 17 includes portions of the San Diego River and San Vicente Creek and adjacent uplands. The unit encompasses approximately 1,595 ha (3,935 ac), of which 75 percent is private land, 17 percent is within the Cleveland National Forest, and 6 percent is Tribal land. The unit is broken into four subunits—three disjunct sections of the San Diego River and one section of San Vicente Creek. Subunit 17a includes approximately 8 km (5 mi) of the San Diego River from Ritchie Creek downstream to the upper edge of El Capitan Reservoir and approximately 1 km (0.6 mi) of lower Cedar Creek. Subunit 17b includes 1.5 km (0.9 mi) of the San Diego River from El Capitan Reservoir to El Monte County Park. Subunit 17c covers almost 7 km (4.3 mi) of the San Diego River from approximately 2 km (1.2 mi) below El Monte County Park downstream to the confluence with San Vicente Creek. Subunit 17d includes 3.9 km (2.4 mi) of San Vicente Creek from the west side of San Diego Country Estates downstream to where the creek crosses Wildcat Canyon Road (the MSCP area boundary).

The upper San Diego River and San Vicente Creek are both occupied by arroyo toads. This unit is essential to arroyo toad conservation because it encompasses several significant populations and includes suitable habitat for population expansion, which increases the probability of long-term persistence. It also provides an important linkage to populations occurring within the San Diego MSCP area. Approximately 100 ha (245 ac) of the Capitan Grande Indian Reservation at the upper end of El Capitan Reservoir are included in this unit. High quality riparian and alluvial terrace habitats occur within the Reservation and they are important portions of the unit.

Unit 18: Sweetwater River Basin, San Diego County

Unit 18 includes portions of the Sweetwater River, Peterson Canyon, Viejas Creek, and adjacent uplands. The unit encompasses approximately 5,065 ha (12,540 ac), of which 55 percent is private land, 22 percent is on California State Park land, 13 percent is within the Cleveland National Forest, and 7 percent is on the San Diego National Wildlife Refuge. The unit is broken into four subunits—three disjunct sections of the Sweetwater River and one section of Viejas Creek. Subunit 18a covers approximately 32 km (20 mi) of the Sweetwater River from the top of Upper Green Valley in Cuyamaca Rancho State Park downstream to the San Diego MSCP area boundary. Subunit 18b includes approximately 1.2 km (0.7 mi) of the Sweetwater River between the MSCP boundary and Loveland Reservoir and 2.4 km (1.5 mi) of Peterson Canyon from just east of the Taylor Creek confluence downstream to the top of Loveland Reservoir. Subunit 18c encompasses approximately 26 km (16 mi) of the Sweetwater River, within the MSCP boundary, from immediately below Loveland Dam downstream to the upper edge of Sweetwater Reservoir. Subunit 18d covers 3.2 km (2 mi) of Viejas Creek and associated uplands from the western end of Viejas Valley downstream to the Congressional boundary of the Cleveland National Forest (which is the eastern boundary of the San Diego MSCP area).

The unit is essential to arroyo toad conservation because it supports several significant populations that can remain viable, and hopefully interconnected, over the long-term, provided suitable habitat conditions are maintained. The unit includes approximately 30 ha (80 ac) of the Viejas Indian Reservation along its southwestern boundary, and 40 ha (100 ac) on the south side of the Sycuan Indian Reservation. High quality riparian and alluvial terrace habitats occur along Viejas Creek (Viejas Reservation) and the lower part of Sycuan Creek (Sycuan Reservation) .

Unit 19: Cottonwood Creek Basin, San Diego County

Unit 19 includes portions of Cottonwood Creek, adjacent uplands, and portions of the following tributaries: Potrero Creek, Pine Valley Creek, Scove Canyon, Morena Creek, La Posta Creek, and Kitchen Creek. This large unit encompasses approximately 7,990 ha (19,740 ac), of which 41 percent is within the Cleveland National Forest, 46 percent is private land, and 11 percent is on land owned by San Diego County. The unit consists of four disjunct subunits—two sections of Cottonwood Creek and two sections of Pine Valley Creek. Subunit 19a covers 13 km (8 mi) of Cottonwood Creek from Buckman Springs (near Interstate 8) downstream to Morena Reservoir and includes approximately 6 km (3.7 mi) of La Posta Creek, 6 km (3.7 mi) of Morena Creek, and 2.5 km (1.6 mi) of Kitchen Creek. Subunit 19b covers almost 16 km (9.9 mi) of Cottonwood Creek from approximately 4 km (2.5 mi) below Morena Reservoir downstream to State Highway 94 (excluding Barrett Reservoir) and includes 15 km (9.3 mi) of Potrero Creek from approximately the 752 m (2,466 ft) elevation benchmark downstream to the confluence with Cottonwood Creek. Subunit 19c covers about 12 km (7.5 mi) of Pine Valley Creek from the north edge of section 12 (T15S, R4E) downstream to approximately 1 km (0.6 mi) south of Interstate 8 and includes approximately 4 km (2.5 mi) of Scove Canyon and 1 km (0.6 mi) of Noble Creek. Subunit 19d encompasses 13 km (8 mi) of Pine Valley Creek from the Nelson Canyon confluence downstream to Barrett Reservoir.

This unit encompasses a large number of distinct arroyo toad occurrences in an area where in-stream and/or overland dispersal between populations is probably still possible. It also provides an important linkage to populations occurring within the San Diego MSCP area. The unit is essential to arroyo toad conservation because it encompasses several large, populations and includes suitable habitat for population expansion, which increases the probability of long-term persistence.

Desert Recovery Unit

The following four critical habitat units are in the Desert Recovery Unit as described in the final recovery plan. Each of these units is isolated from each other and from any other units, making the issues of inbreeding, fragmentation, and random negative impacts of great concern. However, this unit also represents unique ecological conditions for arroyo toads, and possibly harbor significant genetic diversity.

Unit 20: Little Rock Creek, Los Angeles County

Unit 20 includes approximately 9.5 km (5.9 mi) of Little Rock Creek and adjacent uplands, from the South Fork confluence downstream to the upper end of Little Rock Reservoir (in the vicinity of Rocky Point Picnic Ground), and approximately 1.8 km (1.1 mi) of Santiago Creek and adjacent uplands upstream from the confluence with Little Rock Creek. The unit encompasses approximately 600 ha (1,480 ac), all of which is within the Angeles National Forest. Studies are currently under way to better determine the distribution of the arroyo toad population along the creek, monitor recruitment, and assess upland habitat use (Ramirez 2000).

Unit 20 is essential for arroyo toad conservation because it supports a unique, isolated population on the periphery of the species' range. If a natural hydrologic regime can be maintained and impacts from recreation activities can be minimized, the area has favorable habitat conditions for the persistence of a small, but viable, population.

Unit 21: Upper Mojave River Basin, San Bernardino County

Unit 21 includes portions of the Mojave River, the West Fork of the Mojave River, Horsethief and Little Horsethief creeks, Deep Creek, and adjacent uplands. The unit encompasses approximately 6,685 ha (16,520 ac), of which 17 percent is within the San Bernardino National Forest, 60 percent is private land, 8 percent is State or local public land, and 14 percent is U.S. Army Corps of Engineers-managed land associated with a flood control reservoir. The unit is divided into three separate subunits. Subunit 21a includes: (1) approximately 18 km (9.3 mi) of Deep Creek from near Holcomb Creek downstream to the confluence with the West Fork, (2) approximately 6.5 km (4 mi) of Little Horsethief Creek from near the western edge of section 28 (T3N, R5W) downstream to the confluence with Horsethief Creek, (3) approximately 5.5 km (3.4 mi) of Horsethief Creek from the Little Horsethief Creek confluence downstream to the West Fork confluence, (4) just over 7 km (4.3 mi) of the West Fork of the Mojave River from the Horsethief Creek confluence downstream to Mojave River Forks Dam, and (5) approximately 4 km (2.5 mi) of the Mojave River below Mojave River Forks Dam.

Subunit 21b includes approximately 18 km (11 mi) of the Mojave River from just above the Upper Narrows (section 14, T5N, R4W) downstream to approximately 6 km (3.7 mi) below the Lower Narrows (section 13, T6N, R5W). Subunit 21c includes almost 3 km (1.9 mi) of the upper West Fork of the Mojave River, above Silverwood Lake, from near the 1462 m (3,613 ft) elevation benchmark downstream to the upper end of the lake.

All of the designated drainages in this unit are occupied by arroyo toads. Summit Valley, which encompasses the lower portions of Horsethief Creek and the West Fork of the Mojave River, is a broad, flat, alluvial valley that supports a substantial arroyo toad population (Ramirez 1999).

Unit 21 is essential to arroyo toad conservation because it supports the largest population of the species on the desert side of the mountains. If adequate streamflows and upland alluvial habitats can be maintained, this is the one desert unit that has favorable conditions for long-term persistence of a large toad population.

Unit 22: Whitewater River, Riverside County

Unit 22 includes approximately 9.5 km (5.9 mi) of the Whitewater River and adjacent uplands, from near Red Dome downstream to where the Colorado River Aqueduct crosses the river (south half of section 2, T3S, R3E). The unit encompasses approximately 865 ha (2,150 ac), of which 62 percent is BLM land and 38 percent is private land. The current status of arroyo toads in this unit is poorly known. They were observed and photographed in the drainage in 1992 (Jennings and Hayes 1994), but were not relocated in surveys conducted during the 2000 breeding season (Jones & Stokes 2000). However, 2000 was generally a bad year for arroyo toad breeding activity, particularly in the southern half of the species range, because of below average precipitation and subsequent low streamflows. Given the relatively recent documentation of arroyo toads in this drainage, and the

continued presence of suitable habitat in the area, we belive it is likely that this unit is still occupied.

Unit 22 is essential for arroyo toad conservation because it supports a unique, isolated desert population on the eastern periphery of the species' range. Also, if a natural hydrologic regime can be maintained and impacts from recreation activities can be minimized, the area has favorable habitat conditions for the persistence of a small, but viable, population.

Effects of Critical Habitat Designation

Section 7 Consultation

Section 7(a)(2) of the Act requires Federal agencies, including the Service, to ensure that actions they fund, authorize, or carry out do not destroy or adversely modify critical habitat to the extent that the action appreciably diminishes the value of the critical habitat for the survival and recovery of the species. Individuals, organizations, states, local governments, and other non-Federal entities are affected by the designation of critical habitat only if their actions occur on Federal lands, require a Federal permit, license, or other authorization, or involve Federal funding.

Section 7(a) of the Act requires Federal agencies, including the Service, to evaluate their actions with respect to any species that is proposed or listed as endangered or threatened and with respect to its critical habitat, if any is proposed or designated. Regulations implementing this interagency cooperation provision of the Act are codified at 50 CFR part 402. Section 7(a)(4) of the Act, requires Federal agencies to confer with us on any action that is likely to jeopardize the continued existence of a proposed species or result in destruction or adverse modification of proposed critical habitat. Conference reports provide conservation recommendations to assist the agency in eliminating conflicts that may be caused by the proposed action. The conservation recommendations in a conference report are advisory. If a species is listed or critical habitat is designated, section 7(a)(2) requires Federal agencies to ensure that activities they authorize, fund, or carry out are not likely to jeopardize the continued existence of such a species or to destroy or adversely modify its critical habitat. If a Federal action may affect a listed species or its critical habitat, the responsible Federal agency (action agency) must enter into consultation with us. Through this consultation, we would ensure that the permitted actions do not destroy or adversely modify critical habitat.

When we issue a biological opinion concluding that a project is likely to result in the destruction or adverse modification of critical habitat, we also provide reasonable and prudent alternatives to the project, if any are identifiable. “Reasonable and prudent alternatives” are defined at 50 CFR 402.02 as alternative actions identified during consultation that can be implemented in a manner consistent with the intended purpose of the action, that are consistent with the scope of the Federal agency's legal authority and jurisdiction, that are economically and technologically feasible, and that the Director believes would avoid destruction or adverse modification of critical habitat. Reasonable and prudent alternatives can vary from slight project modifications to extensive redesign or relocation of the project. Costs associated with implementing a reasonable and prudent alternative are similarly variable.

Regulations at 50 CFR 402.16 require Federal agencies to reinitiate consultation on previously reviewed actions in instances where critical habitat is subsequently designated and the Federal agency has retained discretionary involvement or control over the action or such discretionary involvement or control is authorized by law. Consequently, some Federal agencies may request reinitiation of consultation or conference with us on actions for which formal consultation has been completed, if those actions may affect designated critical habitat or adversely modify or destroy proposed critical habitat. Conference reports assist the agency in eliminating conflicts that may be caused by the proposed action, and may include recommendations on actions to eliminate conflicts with or adverse modifications to proposed critical habitat. The conservation recommendations in a conference report are advisory.

We may issue a formal conference report if requested by a Federal agency. Formal conference reports on proposed critical habitat contain an opinion that is prepared according to 50 CFR 402.14, as if critical habitat were designated. We may adopt the formal conference report as the biological opinion when the critical habitat is designated, if no substantial new information or changes in the action alter the content of the opinion (see 50 CFR 402.10(d)).

Activities on Federal lands that may affect the arroyo toad or its critical habitat will require section 7 consultation. Activities on private or State lands requiring a permit from a Federal agency, such as a permit from the Army Corps under section 404 of the Clean Water Act, a section 10(a)(1)(B) permit from the Service, or some other Federal action, including funding (
e.g.,
Federal Highway Administration or Federal Emergency Management Agency funding), will also continue to be subject to the section 7 consultation process. Federal actions not affecting listed species or critical habitat and actions on non-Federal and private lands that are not federally funded, authorized, or permitted do not require section 7 consultation.

Section 4(b)(8) of the Act requires us to briefly evaluate and describe in any proposed or final regulation that designates critical habitat those activities involving a Federal action that may destroy or adversely modify such habitat, or that may be affected by such designation. Activities that may destroy or adversely modify critical habitat include those that appreciably reduce the value of critical habitat for both the survival and recovery of the arroyo toad. Within critical habitat, this pertains only to those areas containing primary constituent elements. We note that such activities may also jeopardize the continued existence of the species.

To properly portray the effects of critical habitat designation, we must first compare the section 7 requirements for actions that may affect critical habitat with the requirements for actions that may affect a listed species. Section 7 prohibits actions funded, authorized, or carried out by Federal agencies from jeopardizing the continued existence of a listed species or destroying or adversely modifying the listed species' critical habitat. Actions likely to “jeopardize the continued existence” of a species are those that would appreciably reduce the likelihood of the species' survival and recovery. Actions likely to “destroy or adversely modify” critical habitat are those that would appreciably reduce the value of critical habitat for the survival and recovery of the listed species.

Common to both definitions is an appreciable detrimental effect on both survival and recovery of a listed species. Given the similarity of these definitions, actions likely to destroy or adversely modify critical habitat would almost always result in jeopardy to the species concerned, particularly when the area of the proposed action is occupied by the species concerned. Designation of critical habitat in areas occupied by the arroyo toad is not likely to result in a regulatory burden above that already in place due to the presence of the listed species.

Federal agencies already consult with us on activities in areas currently occupied by the species to ensure that their actions do not jeopardize the continued existence of the species. These actions include, but are not limited to:

(1) Regulation of activities affecting waters of the United States by the Army Corps under section 404 of the Clean Water Act;

(2) Regulation of water flows, damming, diversion, and channelization by any Federal agency;

(3) Road construction and maintenance, right-of-way designation, and regulation of agricultural activities on Federal lands (such as those managed by the Service, Forest Service, DOD, or BLM);

(4) Regulation of grazing, mining, and recreation by the BLM, DOD, Army Corps, or Forest Service;

(5) Regulation of airport improvement activities by the Federal Aviation Administration;

(6) Military training and maneuvers, facilities operations and maintenance on Fort Hunter Liggett and other applicable DOD lands;

(7) Construction of roads and fences along the international border with Mexico, and associated immigration enforcement activities by the Immigration and Naturalization Service (INS);

(8) Licensing of construction of communication sites by the Federal Communications Commission; and,

(9) Funding of activities by the U.S. Environmental Protection Agency, Department of Energy, Federal Emergency Management Agency, Federal Highway Administration, or any other Federal agency.

All lands designated as critical habitat are within the geographic range of the species occupied by the species and are likely to be used by the arroyo toad, whether for foraging, breeding, growth of larvae and juveniles, intra-specific communication, dispersal, migration genetic exchange and sheltering. Thus, we consider all critical habitat units to be occupied by the species. Federal agencies already consult with us on activities in areas currently occupied by the species or if the species may be affected by the action to ensure that their actions do not jeopardize the continued existence of the species. Thus, we do not anticipate additional regulatory protection will result from critical habitat designation.

Exclusions Under Section 3(5)(A) Definition

The Sikes Act Improvement Act of 1997 (Sikes Act) requires each military installation that includes land and water suitable for the conservation and management of natural resources to complete, by November 17, 2001, an Integrated Natural Resources Management Plan (INRMP). An INRMP integrates implementation of the military mission of the installation with stewardship of the natural resources found there. Each INRMP includes an assessment of the ecological needs on the installation, including the need to provide for the conservation of listed species; a statement of goals and priorities; a detailed description of management actions to be implemented to provide for these ecological needs; and a monitoring and adaptive management plan. We consult with the military on the development and implementation of INRMPs for installations with listed species. We believe that bases that have completed and approved INRMPs that address the needs of the species generally do not meet the definition of critical habitat discussed above, as they require no additional special management or protection.

Therefore, we do not include these areas in critical habitat designations if they meet the following three criteria: (1) A current INRMP must be complete and provide a conservation benefit to the species; (2) the plan must provide assurances that the conservation management strategies will be implemented; and (3) the plan must provide assurances that the conservation management strategies will be effective, by providing for periodic monitoring and revisions as necessary. If all of these criteria are met, then the lands covered under the plan would not meet the definition of critical habitat. As the bases where we identified habitat essential for the conservation of the arroyo toad, including Marine Corps Base Camp Pendleton, Fallbrook Naval Weapons Reserve, and Fort Hunter Liggett, do not have INRMPs that meet the criteria, we did not exclude them under the section 3(5)(A) definition.

Exclusions Under Section 4(b)(2)

Subsection 4(b)(2) of the Act allows us to exclude areas from critical habitat designation where the benefits of exclusion outweigh the benefits of designation, provided the exclusion will not result in the extinction of the species. For the following reasons, we believe that in most instances the benefits of excluding HCPs from critical habitat designations will outweigh the benefits of including them.

(1) Benefits of Inclusion

The benefits of including HCP lands in critical habitat are normally small. The principal benefit of any designated critical habitat is that activities in such habitat that may affect it require consultation under section 7 of the Act. Such consultation would ensure that adequate protection is provided to avoid adverse modification of critical habitat. Where HCPs are in place, our experience indicates that this benefit is small or non-existent. Currently approved and permitted HCPs are already designed to ensure the long-term survival of covered species within the plan area. Where we have an approved HCP, lands that we ordinarily would define as critical habitat for the covered species will normally be protected in reserves and other conservation lands by the terms of the HCPs and their implementation agreements. These HCPs and implementation agreements include management measures and protections for conservation lands that are crafted to protect, restore, and enhance their value as habitat for covered species.

In addition, an HCP application must itself be consulted upon. While this consultation will not look specifically at the issue of adverse modification of critical habitat, it will look at the very similar concept of jeopardy to the listed species in the plan area. Because HCPs, particularly large regional HCPs, address land use within the plan boundaries, habitat issues within the plan boundaries will have been thoroughly addressed in the HCP and through the consultation on the HCP. Our experience is also that, under most circumstances, consultations under the jeopardy standard will reach the same result as consultations under the adverse modification standard. Implementing regulations (50 CFR part 402) define “jeopardize the continued existence of” and “destruction or adverse modification of” in virtually identical terms. “Jeopardize the continued existence of” means to engage in an action “that reasonably would be expected to reduce appreciably the likelihood of both the survival and recovery of a listed species.” Destruction or adverse modification means an alteration that appreciably diminishes the value of critical habitat for both the survival and recovery of a listed species.” Common to both definitions is an appreciable detrimental effect on both survival and recovery of a listed species, in the case of critical habitat by reducing the value of the habitat so designated. Thus, actions satisfying the standard for

adverse modification are nearly always found to also jeopardize the species concerned, and the existence of a critical habitat designation does not materially affect the outcome of consultation. Additional measures to protect the habitat from adverse modification are not likely to be required.

Further, HCPs typically provide for greater conservation benefits to a covered species than section 7 consultations because HCPs assure the long term protection and management of a covered species and its habitat, and funding for such management through the standards found in the 5-Point Policy for HCPs (64 FR 35242) and the HCP No Surprises regulation (63 FR 8859). Such assurances are typically not provided by section 7 consultations which, in contrast to HCPs, often do not commit the project proponent to long term special management or protections. Thus, a consultation typically does not accord the lands it covers the extensive benefits an HCP provides.

The development and implementation of HCPs provide other important conservation benefits, including the development of biological information to guide conservation efforts and assist in species recovery and the creation of innovative solutions to conserve species while allowing for development. The educational benefits of critical habitat, including informing the public of areas that are important for the long-term survival and conservation of the species, are essentially the same as those that would occur from the public notice and comment procedures required to establish an HCP, as well as the public participation that occurs in the development of many regional HCPs. For these reasons, then, we believe that designation of critical habitat has little benefit in areas covered by HCPs.

(2) Benefits of Exclusion

The benefits of excluding HCPs from being designated as critical habitat may be more significant. During two public comment periods on our critical habitat policy, we received several comments about the additional regulatory and economic burden of designating critical habitat. These include the need for additional consultation with the Service and the need for additional surveys and information gathering to complete these consultations. HCP applicants have also stated that they are concerned that third parties may challenge HCPs on the basis that they result in adverse modification or destruction of critical habitat, should critical habitat be designated within the HCP boundaries.

The benefits of excluding HCPs include relieving landowners, communities and counties of any additional minor regulatory review that might be imposed by critical habitat. Many HCPs, particularly large regional HCPs, take many years to develop and, upon completion, become regional conservation plans that are consistent with the recovery of covered species. Most regional plans benefit many species, both listed and unlisted. Imposing an additional regulatory review after HCP completion may jeopardize conservation efforts and partnerships in many areas and could be viewed as a disincentive to those developing HCPs. Excluding HCPs provides us with an opportunity to streamline regulatory compliance and confirms regulatory assurances for HCP participants.

A related benefit of excluding HCPs is that it would encourage the continued development of partnerships with HCP participants, including states, local governments, conservation organizations, and private landowners, that together can implement conservation actions we would be unable to accomplish alone. By excluding areas covered by HCPs from critical habitat designation, we preserve these partnerships and, we believe, set the stage for more effective conservation actions in the future.

In general, then, we believe the benefits of critical habitat designation to be small in areas covered by approved HCPs. We also believe that the benefits of excluding HCPs from designation are significant. Weighing the small benefits of inclusion against the benefits of exclusion, including the benefits of relieving property owners of an additional layer of approvals and regulation, together with the encouragement of conservation partnerships, would generally result in HCPs being excluded from critical habitat designation under Section 4(b)(2) of the Act.

Not all HCPs are alike with regard to species coverage and design. Within this general analytical framework, we need to evaluate completed and legally operative HCPs in the range of the arroyo toad on a case-by-case basis to determine whether the benefits of excluding these particular areas outweigh the benefits of including them.

Relationship to Habitat Conservation Plans

Section 4(b)(2) of the Act allows us broad discretion to exclude from critical habitat designation areas where the benefits of exclusion outweigh the benefits of designation, provided the exclusion will not result in the extinction of the species. We expect that critical habitat may be used as a tool to identify those areas essential for the conservation of the species, and we will encourage development of Habitat Conservation Plans (HCPs) for such areas on non-Federal lands. Habitat conservation plans currently under development are intended to provide for protection and management of habitat areas essential for the conservation of the arroyo toad, while directing development and habitat modification to nonessential areas of lower habitat value.

A number of habitat conservation planning efforts have been completed within the range of the arroyo toad. Principal among these are the NCCP/HCP efforts in San Diego and Orange counties. The San Diego MSCP, and its approved subarea plans, provide measures to conserve known populations of the arroyo toad within Santa Ysabel Creek in San Pasqual Valley, San Vicente Creek above San Vicente Reservoir, Sweetwater River, Otay River, and Cottonwood Creek in Marron Valley. Area-specific management directives for MSCP subarea plans must address the conservation of the arroyo toad by protecting and maintaining sufficient, suitable low-gradient sandy stream habitat to meet breeding requirements, preserving sheltering and foraging habitats within 1 km (0.6 mi) of occupied breeding habitat within designated preserve lands, controlling nonnative predators, and controlling human impacts within designated preserves. Several of these plans are currently under development, including ones for Marron and San Pasqual valleys.

One exception to the HCP exclusion concerns the reach of the Sweetwater River between Loveland and Sweetwater Reservoirs within the County of San Diego's MSCP plan. This area is affected by activities (e.g., reservoir water transfers) that are outside the authority of and, therefore, are not subject to the approved County's MSCP plan. Therefore, we have included this limited reach of the Sweetwater River as critical habitat.

We have also approved the Orange County Central Coastal NCCP/HCP, which will result in the conservation of 15,677 ha (38,738 ac) of Reserve lands, including habitat suitable for the arroyo toad. We issued an incidental take permit under section 10(a)(1)(B) of the Act that provides conditional incidental take authorization for the arroyo toad for all areas within the Central-Coastal Subregion except the North Ranch

Policy Plan area. This take authorization only applies to smaller arroyo toad populations, reintroduced populations or populations that have expanded due to NCCP Reserve management and requires implementation of a mitigation plan to relocate toads to protected areas within the Reserve.

The North Ranch Policy Plan area was excluded from the take authorization provided by the Central Coastal NCCP/HCP due to a lack of detailed biological information and specific conservation commitments at the time of adoption of the NCCP/HCP. Further, the NCCP/HCP does not require future adoption of a management plan for the North Ranch Policy Plan area. We have determined that available arroyo toad habitat within the North Ranch Policy Plan area is essential to the conservation of the arroyo toad by helping to support a viable Santa Ana Mountain arroyo toad population. Because the NCCP/HCP affords no long term conservation commitments for this area, we have included a portion of the North Ranch Policy Plan area as critical habitat.

The benefits of excluding lands covered by these HCPs would be significant in preserving positive relationships with our conservation partners, lessening potential additional regulatory review and potential economic burdens, reinforcing the regulatory assurances provided for in the implementation agreements for the approved HCPs, and providing for more established and cooperative partnerships for future conservation efforts.

In summary, the benefits of including these HCPs in critical habitat for the arroyo toad include increased educational benefits and minor additional management protections and measures. The benefits of excluding HCPs from being designated as critical habitat for the arroyo toad include the additional conservation measures for the arroyo toad and other listed species, preservation of partnerships that may lead to future conservation, and the avoidance of the minor regulatory and economic burdens associated with the designation of critical habitat. The benefits of excluding these areas from critical habitat designation outweigh the benefits of including these areas. Furthermore, we have determined that these exclusions will not result in the extinction of the species. We have already completed section 7 consultation on the impacts of these HCPs on the species. We have determined that they will not jeopardize the continued existence of the species, which means that they will not appreciably reduce likelihood of the survival and recovery of the species. Consequently, these lands have not been designated as critical habitat for the arroyo toad.

Habitat conservation plans currently under development are intended to provide for protection and management of habitat areas essential for the conservation of the arroyo toad, while directing development and habitat modification to nonessential areas of lower habitat value. The HCP development process provides an opportunity for more intensive data collection and analysis regarding the use of particular habitat areas by the arroyo toad. The process also enables us to conduct detailed evaluations of the importance of such lands to the long-term survival of the species in the context of constructing a biologically configured system of interlinked habitat blocks. We fully expect that HCPs undertaken by local jurisdictions (e.g., counties, cities) and other parties will identify, protect, and provide appropriate management for those specific lands within the boundaries of the plans that are essential for the long-term conservation of the species. We believe and fully expect that our analyses of proposed HCPs and proposed projects under section 7 will show that covered activities carried out in accordance with the provisions of the HCPs and biological opinions will not result in destruction or adverse modification of critical habitat.

We will provide technical assistance and work closely with applicants throughout the development of future HCPs to identify lands essential for the long-term conservation of the arroyo toad and appropriate conservation and management actions. Several HCP efforts are currently under way that address listed and nonlisted species in areas within the range of the arroyo toad and in areas we propose as critical habitat. The take minimization and mitigation measures provided under these HCPs are expected to protect the essential habitat lands designated as critical habitat in this rule and provide for the conservation of the covered species. If an HCP that addresses the arroyo toad is ultimately approved, the Service will reassess the critical habitat boundaries in light of the HCP. The Service will seek to undertake this review when the HCP is approved, but funding constraints may influence the timing of such a review.

During the public comment period for the proposal, Marine Corps Base Camp Pendleton (Camp Pendleton) submitted comments concluding that critical habitat designation on the base is unnecessary based on existing Marine Corps management plans that provide adequate special management and protection for the species. Arroyo toad numbers on Camp Pendleton are significant and are inclusive of the few remaining populations along the coastal plain. In light of these factors, we proposed 15,445 ha (38,150 ac) of the approximately 50,000 ha (125,000 acre) base as critical habitat for the arroyo toad.

Camp Pendleton's programmatic conservation plan for riparian and estuarine/beach ecosystems does not address arroyo toads in upland habitats. Moreover, the programmatic instructions and conservation measures in the plan need to be revised to avoid and minimize potential adverse effects to the arroyo toad. As the Service indicated in a letter dated February 9, 2000, these revisions include, “but are not limited to, implementation of a base-wide non-native predatory species control program, removal of non-essential road crossings, modification of existing and new road crossings, removal of unnecessary structures and hardscape within arroyo toad breeding and non-breeding habitats, and guidelines on the use of toad exclusion fencing.” To address endangered and threatened species issues within upland habitats on base, on March 30, 2000, at the request of the Marines, we initiated formal consultation with Camp Pendleton on their uplands activities. These activities include military training, maintenance, fire management, real estate, and recreation programs. Because of the immense complexity of dealing with a multitude of hard-to-define upland activities and numerous federally listed plants and animals, we expect completion of the consultation and issuance of our biological opinion to take several months to a year. Upon completion, this consultation will address the 93 percent of the base not included in our 1995 opinion concerning the base's programmatic conservation plan for riparian and estuarine/beach ecosystems (U.S. Fish and Wildlife Service 1995).

The proposal included upland and riparian habitats within key training areas on Camp Pendleton that represent about 30 percent of the base. If this area is included in the final designation of critical habitat for the arroyo toad, the Marines would be compelled by their interpretation of the Endangered Species Act to significantly curtail necessary training within the area designated as critical habitat, to the detriment of mission-critical training capability, until the programmatic uplands consultation is concluded, up to a year from now. Avoiding areas

designated as critical habitat would greatly restrict use of the base, severely limiting the Camp Pendleton's utility as a Marine training site. The Marines have no alternative site suitable for the kinds of training that occur on the base.

In contrast, the benefits of designating critical habitat on the base now are small. The primary benefit of designation is the prohibition on destruction or adverse modification of critical habitat under section 7 of the Act. However, we believe that section 7 consultation on any proposed action on the base that would result in an adverse modification conclusion would also result in a jeopardy conclusion, and we are now engaged in formal consultation with the Marines on their activities in upland habitats on the Camp Pendleton. In addition, the Marines have a statutory obligation under the Sikes Act to complete an INRMP for Camp Pendleton about 10 months from now; we expect that, when completed and adopted, this INRMP will provide equal or greater protection to arroyo toad habitat on the base than a critical habitat designation.

The INRMP for Camp Pendleton will be completed by the statutory deadline of November 17, 2001. We will consult with the Marines under section 7 of the Act on the development and implementation of the INRMP. Today, as neither the INRMP nor the programmatic uplands consultation have yet to be completed and approved, the lands proposed as arroyo toad critical habitat on the base still meet the definition of critical habitat. Nevertheless, we conclude that the benefits of excluding Camp Pendleton exceed the benefits of including the base in the critical habitat designation; further, we have determined that excluding the base will not result in the extinction of the arroyo toad, as numerous areas supporting arroyo toad populations remain within the final critical habitat designation and sections 7(a)(2) and 9 still apply to the activities affecting arroyo toads on Camp Pendleton. Thus, we have determined that it is appropriate to exclude Camp Pendleton from this critical habitat designation under section 4(b)(2). The main benefit of this exclusion is ensuring that the mission-critical military training activities can continue without interruption at Camp Pendleton while the INRMP and programmatic uplands consultation are being completed. This exclusion does not include that part of Camp Pendleton leased to the State of California and included within San Onofre State Park (including San Mateo Park) and those agricultural leased lands adjacent to San Mateo Creek. Because these lands are used minimally, if at all, by the Marines for training, the lands proposed within the state park and agricultural leases are retained in the final designation.

Should additional information become available that changes our analysis of the benefits of excluding any of these (or other) areas compared to the benefits of including them in the critical habitat designation, we may revise this final designation accordingly. Similarly, if new information indicates any of these areas should not be included in the critical habitat designation because they no longer meet the definition of critical habitat, we may revise this final critical habitat designation. If, consistent with available funding and program priorities, we elect to revise this designation, we will do so through a subsequent rulemaking.

If you have questions regarding whether specific activities will constitute adverse modification of critical habitat, contact the Field Supervisor, Ventura or Carlsbad Fish and Wildlife Offices (see
ADDRESSES
section). Requests for copies of the regulations on listed wildlife, and inquiries about prohibitions and permits may be addressed to the U.S. Fish and Wildlife Service, Branch of Endangered Species, 911 NE. 11th Ave, Portland, OR 97232 (telephone 503/231-2063; facsimile 503/231-6243).

Summary of Comments and Recommendations

In the June 8, 2000, proposed rule, (65 FR 36512), we requested all interested parties to submit comments on the specifics of the proposal including information, policy, treatment of HCPs, and proposed critical habitat boundaries as provided in the proposed rule. The first comment period closed on August 7, 2000. The comment period was reopened from November 9 to December 11, 2000 (65 FR 67334), to allow for additional comments on the proposed rule and comments on the draft economic analysis of the proposed critical habitat. We entered comments received from August 8 to November 9, 2000, into the administrative record for the second comment period.

We contacted appropriate Tribes, State and Federal agencies, county governments, elected officials, and other interested parties and invited them to comment. In addition, we invited public comment through the publication of notices in the following newspapers in southern California: Santa Maria Times, Los Angeles Times, Daily News-Press (Victorville), Orange County Register, The Press-Enterprise, North County Times, and the San Diego Union-Tribune. The inclusive dates of these publications were June 10 and 12, 2000, for all papers. In these notices and the proposed rule, we anno

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A01-2253. Public record. Not legal advice.