Endangered and Threatened Wildlife and Plants; Proposed Rule to List the Cactus Ferruginous Pygmy-Owl as Endangered With Critical Habitat in Arizona and Threatened in Texas

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AC85

Endangered and Threatened Wildlife and Plants; Proposed Rule to

List the Cactus Ferruginous Pygmy-Owl as Endangered With Critical

Habitat in Arizona and Threatened in Texas

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: The Fish and Wildlife Service (Service) announces a 12-month

finding on a petition to list the cactus ferruginous pygmy-owl

(Glaucidium brasilianum cactorum) as endangered under the authority of

the Endangered Species Act of 1973, as amended (Act). The Service finds

that the petitioned action is warranted and proposes to list the cactus

ferruginous pygmy-owl as endangered in Arizona, and as threatened in

Texas. Listing is not warranted at this time in its range in Mexico.

The former breeding range of this bird extended from south-central

Arizona south through western Mexico, and from southern Texas south

through northeastern Mexico. Within these regions, the species occurs

in riverbottom woodlands, coastal plain oak associations, thornscrub,

and desertscrub associations.The cactus ferruginous pygmy-owl is

threatened to varying degrees across its range by loss and modification

of habitat, lack of adequate protective regulations, and other factors.

This proposal, if made final, would implement Federal protection

provided by the Act for the cactus ferruginous pygmy-owl in the United

States. Critical habitat is being proposed in Arizona.

DATES: Comments from all interested parties must be received by April

11, 1995: Public hearing requests must be received by February 27,

1995.

ADDRESSES: Comments and materials concerning this proposal should be

sent to the State Supervisor, Arizona Ecological Services State Office,

Fish and Wildlife Service, 3616 West Thomas Road, Suite 6, Phoenix,

Arizona 85019. Comments and materials received will be available for

public inspection, by appointment, during normal business hours at the

above address.

FOR FURTHER INFORMATION CONTACT:

Robert M. Marshall, at the above address (Telephone 602/379-4720).

SUPPLEMENTARY INFORMATION:

Background

The cactus ferruginous pygmy-owl is a small bird, approximately 17

centimeters (6\3/4\ inches) long. Males average 62 grams (g) [2.2

ounces (oz)], females average 75 g (2.6 oz). It is reddish-brown

overall, with a cream-colored belly streaked with reddish-brown. Some

individuals are grayish, rather than reddish-brown. The eyes are

yellow, the crown is lightly streaked, and there are no ear tufts.

Paired black-and-white spots on the nape suggests eyes. The tail is

relatively long for an owl, colored rufous with dark bars. The call of

the diurnal owl, heard chiefly near dawn and dusk, is a monotonous

series of short notes.

The cactus ferruginous pygmy-owl (Order Strigiformes; Family

Strigidae) is one of three subspecies of the ferruginous pygmy-owl. It

occurs from lowland central Arizona south through western Mexico, to

the States of Colima and Michoacan, and from southern Texas south

through the Mexican States of Tamaulipas and Nuevo Leon (Figure 1.).

South of these regions and through Central America, G. b. ridgwayi

replaces G. b. cactorum. Throughout South America, G. b. brasilianum is

the resident subspecies (Fisher 1893, van Rossem 1937, Friedmann et al.

1950, Schaldach 1963, Phillips et al. 1964, de Schauensee 1966, Karalus

and Eckert 1974, Oberholser 1974, Johnsgard 1988).

BILLING CODE 4310-55-M

TP12DE94.001

BILLING CODE 4310-55-C

The cactus ferruginous pygmy-owl (hereafter ``pygmy-owl,'' unless

otherwise noted) was described by van Rossem (1937), based on specimens

from Arizona and Sonora. It is distinguished from G. b. ridgwayi and G.

b. brasilianum by its shorter wings and longer tail, and by generally

lighter coloration (van Rossem 1937, Phillips et al. 1964). G. b.

cactorum occurs in several color morphs, with distinct differences

between regional populations (Sprunt 1955, Burton 1973, Tyler and

Phillips 1978, Johnsgard 1988). Some investigators (e.g. van Rossem

1937, Tewes 1992) have suggested that further taxonomic investigation

is needed, primarily to determine whether the current G. b. cactorum

comprises more than one subspecies. G. b. cactorum is widely recognized

as a valid subspecies (e.g. Friedmann et al. 1950, Blake 1953, Sprunt

1955, Phillips et al. 1964, Monson and Phillips 1981, Millsap and

Johnson 1988, Binford 1989). The American Ornithologists' Union (AOU)

recognized G. b. cactorum in its 1957 Checklist of North American Birds

(AOU 1957), but subsequent lists did not include subspecies (AOU 1983).

Based on these authorities, the Service accepted G. b. cactorum as a

subspecies in 1991 (56 FR 58804), and again in 1993 (58 FR 13045).

The pygmy-owl nests in a cavity in a tree or large columnar cactus.

Cavities may be naturally formed (e.g. knotholes) or excavated by

woodpeckers. No nest lining material is used. The pygmy-owl has also

nested in fabricated nest boxes (S. Beasom, Texas Arts and Industries

University, in litt.). Three, four, or sometimes five eggs are laid

(Bent 1938, Heintzelman 1979) and incubated for approximately 28 days.

The young fledge about 28 days after hatching. The pygmy-owl begins

nesting activity in late winter to early spring. It is nonmigratory

throughout its range (Bendire 1888, Griscom and Crosby 1926, Oberholser

1974, Johnson et al. 1979). The pygmy-owl's diverse diet includes

birds, lizards, insects, small mammals (Bendire 1888, Sutton 1951,

Sprunt 1955, Earhart and Johnson 1970, Oberholser 1974), and even frogs

and earthworms (S. Beasom, in litt.).

The pygmy-owl occurs in a variety of subtropical scrub and woodland

communities, including riverbottom woodlands, woody thickets

(``bosques''), coastal plain oak associations, thornscrub, and

desertscrub. Unifying habitat characteristics among these communities

are fairly dense woody thickets or woodlands, with trees and/or cacti

large enough to provide nesting cavities. Throughout its range, the

pygmy-owl occurs at low elevations, generally below 1,200 meters (m) or

4,000 feet (ft) (Swarth 1914, Karalus and Eckert 1974, Monson and

Phillips 1981, Johnsgard 1988, Enriquez-Rocha et al. 1993). In southern

Texas, the pygmy-owl's habitat includes coastal plain oak associations,

and the Tamaulipan Thornscrub of the lower Rio Grande valley region,

which is comprised of mesquite (Prosopis glandulosa), hackberry (Celtis

spp.), oak (Quercus spp.), and Texas ebony (Pithecellobium ebano)

(Griscom and Crosby 1926, Bent 1938, Oberholser 1974, Tewes 1992, Wauer

et al. 1993). In northeastern Mexico, it occurs in lowland thickets,

thornscrub communities, riparian woodlands, and second-growth forest

(van Rossem 1945, AOU 1983, Tewes 1992, Enriquez-Rocha et al. 1993). In

central and southern Arizona, the pygmy-owl's primary habitats are

riparian cottonwood (Populus spp.) forests and mesquite bosques. Also

in central and southern Arizona, the pygmy-owl occurs in Sonoran

Desertscrub associations of paloverde (Cercidium spp.), bursage

(Ambrosia spp.), ironwood (Olneya tesota), mesquite (Prosopis

juliflora), acacia (Acacia spp.), and giant cacti like the saguaro

(Cereus giganteus), and organpipe (Cereus thurberi) (Gilman 1909, Bent

1938, van Rossem 1945, Phillips et al. 1964, Monson and Phillips 1981,

Johnson-Duncan et al. 1988, Millsap and Johnson 1988). Farther south in

northwestern Mexico, the pygmy-owl occurs in Sonoran Desertscrub,

Sinaloan Thornscrub, and Sinaloan Deciduous Forest as well as

riverbottom woodlands, cactus forests and thornforest (Enriquez-Rocha

et al. 1993, G. Monson in prep.).

The available information indicates that distinct eastern and

western populations of the pygmy-owl may be defined (Figure 1.). The

pygmy-owl occurs along the lower Rio Grande River and the coastal plain

of southern Texas and northeastern Mexico. It also occurs in lowland

areas of northwestern Mexico and southern Arizona. The pygmy-owl's

elevational distribution, the distribution of habitat, and recorded

locations indicate that these eastern and western ranges of the pygmy-

owl are geographically isolated from one another and are ecologically

distinct. In the U.S., the eastern and western portions of the pygmy-

owl's range are separated by the basin-and-range mountains and

intervening Chihuahuan Desert basins of southeastern Arizona, southern

New Mexico, and western Texas. Although Grossman and Hamlet (1964)

suggested that the pygmy-owl's range included this U.S.-Mexico border

region, the pygmy-owl has never been recorded in this 500-mile (mi)

wide area (Bailey 1928, Phillips et al. 1964, Oberholser 1974, S.O.

Williams, New Mexico Department of Game and Fish, in litt.).

In Mexico, the eastern and western populations are separated by the

highlands of the Sierra Madre Oriental and Occidental, and the Mexican

Plateau. The pygmy-owl is considered rare on the Mexican Plateau and/or

above elevations of 1,200 m (4,000 ft) on the west, and above 330 m

(1,000 ft) on the east (Friedman et al. 1950). Some sources describe

the eastern and western ranges as contiguous at the southern end of its

range, near the southern end of the Mexican Plateau in central Mexico

(Johnsgard 1988). Other sources (e.g., Burton 1973) describe these two

ranges as being disjunct. In his description of the subspecies, van

Rossem (1937) found that Texas specimens exhibited characteristics of

both G. b. cactorum and G. b. ridgwayi. Ultimately, he did not assign

Texas ferruginous pygmy-owls to G. b. cactorum, noted that Ridgway

(1914, in van Rossem 1937) considered them distinct from G. b.

ridgwayi, and left the taxonomy of Texas G. brasilianum open. Most

authors have subsequently considered Texas pygmy-owls to be G. b.

cactorum (e.g., Oberholser 1974, Millsap and Johnson 1988).

In addition to geographic separation, the pygmy-owl's eastern and

western populations occupy different habitats. Although some broad

similarities in habitat physiognomy are apparent (e.g., dense woodlands

and thickets), floristically these eastern and western habitats are

very dissimilar. The desertscrub and thornscrub associations in Arizona

and western Mexico are unlikely any habitats occupied by the pygmy-owl

in eastern Mexico and southern Texas. Also, the oak association habitat

occupied on coastal plains in southern Texas is unlike any habitat

available in the western portion of the pygmy-owl's range. However, the

Tamaulipan thornscrub habitat of the east and the riverbottom mesquite-

cottonwood bosque habitat once found in Arizona are more similar in

physiognomy and to a slight degree in floristic makeup.

The potential for genetic distinctness further supports identifying

eastern and western pygmy-owl populations. The fact that the pygmy-owl

is nonmigratory throughout its range suggests that genetic mixing

across wide areas may be infrequent. Considerable variation in plumage

between regional populations has been noted, including specific

distinctions between Arizona and Texas pygmy-owls (van Rossem 1937,

Burton 1973, Tyler and Phillips 1978, Johnsgard 1988).

The above information indicates that eastern and western

populations of the cactus ferruginous pygmy-owl are distinct, based on

geographic isolation, potential morphological and genetic distinctness,

and distribution and status of habitat. These eastern and western

populations of the pygmy-owl may be considered separately for listing

under the Act, as ``* * * any subspecies * * * and any distinct

population segment of any species of vertebrate which interbreeds when

mature'' [Section 3(16)]. Further, the status of the species in Mexico

is currently unclear (see discussion under ``Factor A'', below).

The above criteria lead the Service to consider four separate

populations of G. b. cactorum for listing purposes: western U.S.

(Arizona), eastern U.S. (Texas), western Mexico, and eastern Mexico.

Because the levels of threat, habitats occupied, quality of

information, and overall status differ among these four populations,

the Service herein proposes separate actions for various population

segments.

The Service included the pygmy-owl on its Animal Notice of Review

as a category 2 candidate species throughout its range on January 6,

1989 (54 FR 554). After soliciting and reviewing additional

information, the Service elevated G. b. cactorum to category 1

candidate status throughout its range on November 21, 1991 (56 FR

58804). A category 1 species is one for which the Service has on file

substantial information to support listing, but a proposal to list has

not been issued because it is precluded at present by other listing

activity.

Based on an extensive review of information on the species, it is

now appropriate to list the U.S. populations, while continuing to

review the species in Mexico to determine whether Mexican populations

should be proposed for listing. Recent information from Mexico

indicates that the species may be more abundant, at least in the

southern portion of its range, than originally thought.

On May 26, 1992, a coalition of conservation organizations (Galvin

et al. 1992) petitioned the Service, requesting listing of the pygmy-

owl as an endangered species under the Act. The petitioners also

requested designation of critical habitat. In accordance with Section

4(b)(3)(A) of the Act, on March 9, 1993, the Service published a

finding that the petition presented substantial scientific or

commercial information indicating that listing may be warranted, and

commenced a status review on the pygmy-owl (58 FR 13045). In conducting

its status review, the Service solicited additional comments and

biological data on the status of the cactus ferruginous pygmy-owl,

through mailings, a notice in the Federal Register (58 FR 13045), and

other means.

Section 4(b)(3)(B) of the Act requires the Secretary of the

Interior to reach a final decision on any petition accepted for review

within 12 months of its receipt (16 U.S.C. Sec. 1531 et seq.). That

decision, to be published in the Federal Register, must be one of the

following findings: (1) The petitioned action is not warranted; (2) the

petitioned action is warranted (a proposed regulation is published); or

(3) the petitioned action is warranted, but the immediate proposal is

precluded by listing actions of higher priority. This proposal

constitutes a 1-year finding with respect to the petition that listing

as endangered is warranted for the Arizona population, listing as

threatened is warranted for the Texas population, and listing is not

now warranted for the two populations in Mexico.

Since designating the pygmy-owl as a category 1 species, in the

course of its continuing status review, the Service has acquired

significant new information on the cactus ferruginous pygmy-owl. This

finding is based on various documents, including published and

unpublished studies, agency documents, and field survey records. All

documents on which this finding is based are on file in the Fish and

Wildlife Service Ecological Service State Office in Phoenix, Arizona.

For an explanation of the relationship between petition findings and

candidate category status, see 58 FR 28034 (May 12, 1993).

Summary of Factors Affecting the Species

Section 4(a)(1) of the Act and regulations (50 CFR Part 424)

promulgated to implement the listing provisions of the Act set forth

the procedures for adding species to the Federal List of Endangered and

Threatened Wildlife and Plants. A species may be determined to be an

endangered or threatened species owing to one or more of the five

factors described in Section 4(a)(1). These factors and their

application to the cactus ferruginous pygmy-owl (Glaucidium brasilianum

cactorum) are as follows:

A. The present or threatened destruction, modification, or

curtailment of its habitat or range. The cactus ferruginous pygmy-owl

is threatened by past, present, and potential future destruction and

modification of its habitat, throughout a significant portion of its

range in the U.S., and, to a less well-known extent, in portions of its

range in Mexico (Phillips et al. 1964, Oberholser 1974, Johnson et al.

1979, Monson and Phillips 1981, Johnson and Haight 1985a, Hunter 1988,

Millsap and Johnson 1988, Tewes 1992). The severity of habitat loss and

threats varies across the pygmy-owl's range. It has been virtually

extirpated from Arizona, which once constituted its major U.S. range

(see Figure 1). In Texas, the pygmy-owl has been virtually extirpated

from the lower Rio Grande valley, but persists in oak associations on

the coastal plain north of the Rio Grande valley. The majority of these

losses are because of destruction and modification of riparian and

thornscrub habitats. Wide-scale loss and modification of up to 90

percent of riparian habitats in the southwestern U.S. have occurred

(e.g. Phillips et al. 1964, Carothers 1977, Kusler 1985, General

Accounting Office 1988, Jahrsdoerfer and Leslie 1988, Szaro 1989, Dahl

1990, State of Arizona 1990, Bahre 1991). These losses are attributed

to urban and agricultural encroachment, woodcutting, water diversion,

channelization, livestock overgrazing, groundwater pumping, and

hydrological changes resulting from various land-use practices. Status

information for Mexico is very limited, but some observations suggest

that although habitat loss and reduced numbers are likely to have

occurred in northern portions of the two populations in Mexico, the

pygmy-owl persists as a locally common bird in southern portions.

Habitat loss and population status are summarized below for the four

populations of the pygmy-owl.

Western Populations

Several habitat types are used by the pygmy-owl in the western

portion of its range. These include riparian woodlands and bosques

dominated by mesquite and cottonwood, Sonoran Desertscrub (usually with

relatively dense saguaro cactus forests), Sinaloan Thornscrub, and

Sinaloan Deciduous Forest (van Rossem 1945, Phillips et al. 1964,

Karalus and Eckert 1974, Millsap and Johnson 1988, Monson and Russell

in prep.).

1. Arizona

The northernmost record for the pygmy-owl is from New River,

Arizona, approximately 55 kilometers (km) (35 mi) north of Phoenix,

where Fisher (1893) found it to be ``quite common'' in thickets of

intermixed mesquite and saguaro cactus. Prior to the mid-1900's, the

pygmy-owl was also described as a ``common,'' ``abundant,'' ``not

uncommon,'' and ``fairly numerous'' resident of lowland central and

southern Arizona, in cottonwood forests, mesquite-cottonwood woodlands,

and mesquite bosques along the Gila, Salt, Verde, San Pedro, and Santa

Cruz Rivers, and various tributaries (Coues 1872, Bendire 1888,

Breninger 1898 in Bent 1938, Gilman 1909, Swarth 1914, Friedmann et al.

1950, Phillips et al. 1964, Johnson and Simpson 1971, Millsap and

Johnson 1988). The pygmy-owl also occurs in Sonoran Desertscrub

associations in southern and southwestern Arizona, comprised of

paloverde, ironwood, mesquite, acacia, bursage, and columnar cacti like

the saguaro and organpipe (Phillips et al. 1964, Davis and Russell 1984

and 1990, Monson and Phillips 1981, Johnson and Haight 1985a). the

pygmy-owl's occurrence in Sonoran Desertscrub has apparently always

been uncommon and unpredictable.

However, it seems to be more predictably found in xeroriparian

habitats (very dense desertscrub thickets bordering dry desert washes)

than more open desert uplands (Monson and Phillips 1981, Johnson and

Haight 1985a, Johnson-Duncan et al. 1988, Millsap and Johnson 1988,

Davis and Russell 1990). The pygmy-owl may also occur at isolated

desert oases which support small pockets of riparian or xeroriparian

vegetation (Howell 1916, Phillips et al. 1964).

The above habitats are likely to provide several requirements of

pygmy-owl ecology. Trees and large cacti provide cavities for nesting

and roosting. Also, these habitats along watercourses are known for

their high density and diversity of animal species that constitute the

pygmy-owl's prey base (Carothers 1977, Johnson et al. 1977, Johnson and

Haight 1985b, Stromberg 1993).

The pygmy-owl has declined throughout Arizona to the degree that it

is now virtually extirpated from the State [Johnson et al. 1979, Monson

and Phillips 1981, Arizona Game and Fish Department (AGFD) 1988,

Johnson-Duncan et al. 1988, and Millsap and Johnson 1988]. Riverbottom

forests and bosques, which supported the greatest abundance of pygmy-

owls, have been extensively modified and destroyed by clearing,

urbanization, water management, and hydrological changes (Willard 1912,

Brown et al. 1977, Rea 1983, Szaro 1989, Bahre 1991, Stromberg et al.

1992, Stromberg 1993). Cutting for domestic and industrial fuelwood was

so extensive throughout southern Arizona that, by the late 19th

century, riparian forests within tens of miles of towns and mines had

been decimated (Bahre 1991). Mesquite was a favored species, because of

its excellent fuel qualities. The famous, vast forests of ``giant

mesquites'' along the Santa Cruz River in the Tucson area described by

Swarth (1905) and Willard (1912) fell to this threat, as did the

``heavy mesquite thickets'' where Bendire (1888) collected pygmy-owl

specimens along Rillito Creek, a Santa Cruz River tributary, also in

what is now Tucson. Only remnant fragments of these bosques remain.

Cottonwoods were also felled for fuelwood, fenceposts, and for the

bark, which was used as cattle feed (Bahre 1991). In recent decades,

the pygmy-owl's riparian habitat has continued to be modified and

destroyed by agricultural development, woodcutting, urban expansion,

and general watershed degradation (Brown et al. 1977, Phillips et al.

1964, State of Arizona 1990, Bahre 1991, Stromberg et al. 1992,

Stromberg 1993).

The trend of Sonoran Desertscrub habitats and pygmy-owl occupancy

is not as clear. Historical records from this habitat in Arizona are

few. This may be due to disproportionate collecting along rivers where

humans were concentrated, while the upland deserts were less

intensively surveyed. Johnson and Haight (1985a) suggested that the

pygmy-owl adapted to upland cactus associations and xeroriparian

habitats in response to the demise of Arizona's riverbottom woodlands.

However, conclusive evidence to support this hypothesis is not

available. It may be that desertscrub habitats simply are of lesser

quality, and have always been occupied by pygmy-owls at lower frequency

and density (Johnson and Haight 1985b, Taylor 1986). The few pygmy-owls

located in recent years have been fairly evenly distributed between

remaining riverbottom woodlands, desertscrub, and xeroriparian

habitats. Sonoran Desertscrub has been affected to varying degrees by

urban and agricultural development, woodcutting, and livestock grazing

(Bahre 1991).

Hunter (1988) found fewer than 20 verified records of pygmy-owls in

Arizona for the period of 1971 to 1988. In 1992, surveys located three

single pygmy-owls in Arizona (Fish and Wildlife Service and National

Park Service, unpubl. data, SWCA, Inc. 1993). In 1993, more extensive

surveys again located three single pygmy-owls in Arizona (Felley and

Corman 1993, AGFD and Service, unpubl. data). Although G. b. cactorum

is diurnal and frequently vocalizes in the morning, the species was not

recorded or reported in breeding bird survey data (Robbins et al.

1986).

In addition to clearing woodlands, the diversion and channelization

of natural watercourses, and pumping groundwater, are also likely to

have reduced G. b. cactorum habitat. Diversion and pumping result in

diminished surface flows, and consequent reductions in riparian

vegetation are likely (Brown et. al. 1977, Strombery et al. 1992,

Stromberg 1993). Channelization often alters stream banks and fluvial

dynamics necessary to maintain native riparian vegetation. The series

of dams along most major southwestern rivers (e.g., the Colorado, Gila,

Salt, Verde) have altered riparian habitat downstream of dams through

hydrological and vegetational changes, and have inundated habitat

upstream.

Overuse by livestock has been a major factor in the degradation and

modification of riparian habitat in the western U.S. These effects

include changes in plant community structure and species composition

and relative abundance of species and plant density. These changes are

often linked to more widespread changes in watershed hydrology (Brown

et al. 1977, Rea 1983, GAP 1988). These changes are likely to affect

the habitat characteristics critical to G. b. cactorum. Livestock

grazing in riparian habitats is one of the most common causes of

riparian degradation (e.g., Ames 1977, Carothers 1977, Behnke and

Raleigh 1978, General Accounting Office 1988, Forest Service 1979).

Potential future threats to pygmy-owl habitat also exist. Expanding

human populations in the border region are expected to continue to

increase impacts and threats discussed above. Further, extensive

industrial, municipal, and agricultural developments facilitated by the

Northern American Free Trade Agreement are anticipated along the U.S.-

Mexico border. These developments may result in accelerated habitat

loss and demands on groundwater.

2. Western Mexico

The pygmy-owl occurs in the more arid lower elevations (below 1,200

m (4,000 ft) elevation) in western Mexico, in riparian woodlands and

communities of thornscrub and large cacti. The pygmy-owl is absent or

rare in the highlands of Mexico's central plateau (Friedmann et al.

1950), where the least (G. minustissima) and northern (G. qnoma) pygmy-

owls occur.

In the mid-20th century, the pygmy-owl was generally described as

having been common in western Mexico (van Rossem 1945, Friedmann et al.

1950, Blake 1953). Schaldach (1963) considered the pygmy-owl abundant

in Colima, at the southern extreme of its range, 30 years ago. Fifth

years ago, the pygmy-owl was considered ``fairly common'' in the lower

elevations of western Sonora (van Rossem 1945). Current information on

the status of the pygmy-owl and its habitat in western Mexico is

incomplete, but suggests that trends vary within different geographic

areas. The pygmy-owl can still be located fairly easily in southern

Sonora (Babbitt 1985, T. Corman, AGFD, pers. comm.), but its

distribution is somewhat erratic. Christmas Bird Count data from 1972

through 1991 from Alamos, Sonora, and San Blas, Nayarit, indicate that

the pygmy-owl was not uncommon, but detections varied widely from year

to year (National Audubon Society 1972-1992). In recent years it has

been found in abundance in some areas but is absent in others, in

apparently similar habitat. Abundance also varies between habitat

types, being more abundant in thorn forest than cactus forest (Taylor

1986). The pygmy-owl is now rare or absent in northern Sonora, within

150 miles of the U.S.-Mexico border (Hunter 1988, Monson and Russell in

prep., AGFD in litt.). Extensive conversion of desertscrub and

thornscrub to the exotic bufflegrass (Cenchrus ciliarus) for livestock

forage is known to be taking place, but quantification is not currently

available. It is possible that the factors causing declines in Arizona

are also having effects in western Mexico (Deloya 1985, Hunter 1988).

However, further information is needed before determining whether it

should be listed in western Mexico.

Eastern Populations

Several habitat types are also used by the pygmy-owl in the eastern

portion of its range. These include coastal plain oak associations in

south Texas (Tewes 1992, Wauer et al. 1993), Tamaulipan Thornscrub in

the lower Rio Grande valley and other lowland areas, and thick forest

and second-growth forest in Nuevo Leon and Tamaulipas.

1. Texas

The pygmy-owl's historical range in Texas included the lower Rio

Grande valley, where it was considered a common resident of dense

mesquite-cottonwood-ebony woodlands and Tamaulipan brushland (Griscom

and Crosby 1926, Bent 1938, Friedmann et al. 1950, Stillwell and

Stillwell 1954, Oberholser 1974, Millsap and Johnson 1988). The pygmy-

owl also occurs in coastal plain oak associations between Brownsville

and Corpus Christi (Oberholser 1974), where it has recently been found

in significant numbers (Wauer et al. 1993, S. Beasom in litt., P.

Palmer in litt.).

The pygmy-owl has declined throughout a significant portion of its

Texas range (Oberholser 1974, Johnson et al. 1979, Johnson and Haight

1985a, Millsap and Johnson 1988, Tewes 1992). It appears to persist in

relatively high numbers in coastal plain oak associations north of the

lower Rio Grande valley (Wauer et al. 1993). The pygmy-owl was

described as a common breeding bird in the lower Rio Grande valley near

Brownville in the early 1900's (Griscom and Crosby 1926, Friedmann et

al. 1950), but was considered to have become rare in that region by

mid-century (Wolfe 1956, Oberholser 1974). Pygmy-owls have been seen

less frequently in recent years and in fewer numbers (Oberholser 1974,

Hunter 1988, Wauer et al. 1993). Tewes (1992) found no pygmy-owls in a

1991 survey of the lower Rio Grande valley, but sporadic reports of

single birds continue.

Habitat has been, and continues to be, lost and modified along the

lower Rio Grande valley, chiefly through agricultural development and

urban expansion. Since the early 1900's, approximately 95 percent of

native Tamaulipan Brushland in the lower Rio Grande valley has been

cleared for agriculture, urban development, and recreation

(Jahrsdoerfer and Leslie 1988). By reducing river flow, water

development has further altered or destroyed brushland in riparian

areas.

Impacts on coastal oak associations are less well known, but appear

to be lesser. Limited oak clearing has taken place, but extensive

habitat remains. Little net quantitative change in this habitat appears

to have occurred in the last 100 years, and the habitat may have

increased in the late 1600's and early 1700's (Wauer et al. 1993, P.

Palmer in litt.). Pygmy-owls are currently found in this habitat in

their greatest numbers in the U.S.

Other causes of habitat decline in Texas include alteration of

water regimes and overuse by livestock, both of which have degraded the

riparian ecosystems of the lower Rio Grande (see discussion of these

factors under ``Arizona'', above). However, in a nonriparian grassland/

woodland mosaic in Texas, Wauer et al. (1993) believed livestock

grazing may have increased pygmy-owl habitat by suppressing grasslands

and allowing encroachment by oak associations.

Potential future threats to pygmy-owl habitat also exist. In

coastal Texas, placement of spoil from offshore dredging operations may

impact coastal oak associations. Expanding human populations in the

border region are expected to continue to increase impacts and threats

discussed above. Further, extensive industrial, municipal, and

agricultural developments facilitated by the North American Free Trade

Agreement are anticipated along the U.S.-Mexico border. These

developments may result in accelerated habitat loss and demands on

groundwater.

2. Eastern Mexico

The pygmy-owl occurs in lowland regions [below 330 m (1,000 ft)]

along the Gulf Coast of northeastern Mexico (Friedmann et al. 1950), in

the States of Tamaulipas and Nuevo Leon. Its primary habitat in this

region is Tamaulipan thornscrub, forest edge, riparian woodlands,

thickets, and lowland tropical deciduous forest (Webster 1974, Tewes

1992, Enriquez-Rocha et al. 1993). The pygmy-owl is absent or rare in

the highlands of Mexico's central plateau (Friedmann et al. 1950),

where the least and northern pygmy-owls occur.

In the mid-20th century, the pygmy-owl was generally described as

having been common in eastern Mexico (Friedmann et al. 1950, Blake

1953). Current information on the status of the pygmy-owl and its

habitat in eastern Mexico is incomplete. In 1976, the pygmy-owl was

reported to be ``fairly common'' in the Sierra Picachos of Nuevo Leon

(Arvin 1976). In 1991, Texas (1992) located pygmy-owls at 13 of 27

survey sites in northeastern Mexico. Tewes (1992) believed expansion of

the human population could reduce available habitat in the region

surveyed, but also noted that pygmy-owls were found within larger towns

in the region. Wauer et al. (1993) believed no populations in

northeastern Mexico appeared to be sizable enough to provide

recruitment for other areas. Christmas Bird Count data from 1972

through 1992 from Rio Corona and Gomez Farias, both in Tamaulipas,

indicate the pygmy-owl was not uncommon, but detections varied widely

from year to year (National Audubon Society 1972-1992). Christmas Bird

Count data indicated the same for ferruginous pygmy-owls at El Naranjo

in San Louis Potosi, at the zone of probably intergradation between

G.b. cactorum and G.b. ridgwayi. It is possible that the factors

causing declines in Texas are also having effects in Mexico (Deloya

1985, Hunter 1988). However, further information on the subspecies is

needed before determining whether it should be listed in eastern

Mexico.

B. Overutilization for commercial, recreational, scientific, or

educational purposes. The pygmy-owl is highly sought by bird watchers,

who concentrate at several of the remaining known locations of pygmy-

owls in the U.S. While limited, careful bird watching is probably not

harmful, excess attention by bird watchers may at times constitute

harassment, affecting the occurrence and behavior of the pygmy-owl

(Oberholser 1974, Tewes 1992). For example, in early 1993, one of the

few areas in Texas known to support the pygmy-owl continued to be

widely publicized (American Birding Association 1993). The resident

pygmy-owls were not detected at this highly-visited area after early in

the breeding season. The Service is unaware of any other overuse, for

any purpose, which constitutes a threat to the pygmy-owl.

c. Disease or predation. The Service is unaware of any disease or

predation which constitutes a significant threat to G. b. cactorum.

D. The inadequacy of existing regulatory mechanisms. The Migratory

Bird Treaty Act (MBTA) (16 U.S.C. 703-712) is the only direct, current

Federal protection provided for the cactus ferruginous pygmy-owl. The

MBTA prohibits ``take'' of any migratory bird. ``Take'' is defined as

``* * * to pursue, hunt, shoot, wound, kill, trap, capture, or collect,

or attempt to pursue, hunt, shoot, wound, kill, trap, capture, or

collect.'' However, unlike the Endangered Species Act, there are no

provisions in the MBTA preventing habitat destruction unless direct

mortality or destruction of active nests occurs.

The Federal Clean Water Act contains provisions for regulating

impacts to river systems and their tributaries. These mechanisms have

been insufficient to prevent major losses of riparian habitat,

including habitats occupied by the pygmy-owl.

The State of Arizona lists the ferruginous pygmy-owl (subspecies

not defined) as endangered (AGFD 1988). However, this designation does

not provide special regulatory protection. Arizona regulates the

capture, handling, transportation, and take of most wildlife, including

G. b. cactorum, through game laws, special licenses, and permits for

scientific investigation. However, habitat is not protected under

Arizona endangered species law.

The State of Texas lists the ferruginous pygmy-owl (subspecies not

defined) as threatened (Texas Parks and Wildlife Department 1978 and

1984). This designation requires permits for take for propagation,

zoological gardens, aquariums, rehabilitation purposes, and scientific

purposes (State of Texas 1991). Again, however, there are no provisions

for habitat protection. The pygmy-owl is also on the Texas Organization

for Endangered Species' (TOES) ``watch list'' (TOES 1984).

Most Federal agencies have policies to protect species listed by

States as threatened or endangered, and some also protect species that

are candidates for Federal listing. For example, the National Park

Service protects all wildlife within most National Parks and Monuments.

However, until agencies develop specific protection guidelines,

evaluate their effectiveness, and institutionalize their

implementation, it is uncertain whether any general agency policies

adequately protect the pygmy-owl and its habitat.

No conservation plans or habitat restoration projects specific to

the cactus ferruginous pygmy-owl exist for lands managed by the U.S.

Government, Indian Nations, State agencies, or private parties. The

Forest Service, Bureau of Land Management, and Bureau of Reclamation

have focussed some attention on modifying livestock grazing practices

in recent years, particularly as they affect riparian ecosystems.

Several of those projects are in the former range of G. b. cactorum,

including some historical nesting locations. In addition, some private

landowners in Southern Texas are accommodating research and have

expressed interest in carrying out conservation measures to benefit the

pygmy-owl.

E. Other natural or manmade factors affecting its continued

existence. The riparian woodland habitat of G. b. cactorum was always

rare and has become even more so. Its habitat rarity, and small,

isolated populations make the remaining G. b. cactorum increasingly

susceptible to local extirpation through land development, predation,

and stochastic events such as catastrophic floods and fires.

The disjunct nature of habitats, small breeding populations, and

nonmigratory status may also impede the flow of genetic material

between populations and reduce the chance of demographic and genetic

rescue from immigration for adjacent populations. The resulting

constraints on the gene pool intensify the external threats to the

pygmy-owl.

The pygmy-owl's occurrence in floodplain areas that are now largely

agricultural may indicate a potential threat from pesticides. Where

populations remain, they are sometimes in proximity to agricultural

areas, with associated pesticides and herbicides. Without appropriate

precautions, these agents may potentially affect G. b. cactorum through

direct toxicity or effects on their food base. No quantitative data on

this potential threat are known at this time.

This pygmy-owl nests in cavities excavated by woodpeckers in trees

or large cacti. Some sources (AGFD 1988) believe that increasing

competition with the exotic European starling for nest cavities may be

a threat to cavity nesters like the pygmy-owl.

The Service has carefully assessed the best scientific and

commercial information available regarding the past, present, and

future threats faced by this species in determining to propose this

rule. Based on this evaluation, the preferred action is to list the

cactus ferruginous pygmy-owl (Glaucidium brasilianum cactorum) as

endangered in Arizona, where it is nearly extirpated and is in imminent

danger of imminent danger of disappearing, and as threatened in Texas,

where it has undergone significant decline but is not in danger of

extinction. The Service will continue to review the status of the

species in Mexico.

Critical Habitat

Critical habitat, as defined by Section 3 of the Act, means:

(i) The specific areas within the geographical 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 geographical 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.

Section 4(a)(3) of the Act requires that critical habitat be

designated to the maximum extent prudent and determinable concurrently

with the determination that a species is endangered or threatened.

Critical habitat is being proposed for the cactus ferruginous pygmy-owl

to include riparian thickets, forests, and woodlands along streams,

rivers, and ephemeral drainages in Arizona. The following areas

proposed as critical habitat (all legal descriptions are from the Gila

and Salt River Meridian):

1. Arizona, Maricopa County: approximately 21 km (13 mi) along the

Salt River, from Stewart Mountain Dam to Granite Reef Dam.

2. Arizona, Maricopa County: approximately 39 km (24 mi) along the

Verde River, from Bartlett Dam to the confluence of the Verde and Salt

Rivers.

3. Arizona, Cochise, Pima, and Pinal Counties: approximately 97 km

(60 mi) along the San Pedro River, from the confluence of Soza Canyon

to the confluence of the San Pedro and Gila Rivers, including Cook's

Lake.

4. Arizona, Pima County: approximately 42 km (26 mi) along the

Santa Cruz River, from the Interstate 19 bridge downstream to the Avra

Valley Road bridge.

5. Arizona, Pima County: approximately 54 km (34 mi) along the

Rillito Creek system, from the confluence of Rillito Creek and the

Santa Cruz River upstream, along Tanque Verde Creek to the boundary

between sections 2 and 3, Township 14 south, Range 16 east, and

upstream along Agua Caliente Creek to the Soldier Trail crossing.

6. Arizona, Pima County: approximately 23 km (14 mi) along Canada

del Oro, from its confluence with Sutherland Wash downstream to its

confluence with the Santa Cruz River.

7. Arizona, Pima County: approximately 45 km (28 mi) along Alamo

Wash and Growler Wash, from the well in Alamo Canyon (T16S, R4W,

unsurveyed Section 6) downstream to the point where Growler Wash

intersects the Bates Well Road.

8. Arizona, Pima County: approximately 13 km (8 mi) along Arivaca

Creek, from the road crossing in the town of Arivaca downstream to the

confluence with San Luis Wash.

9. Arizona, Greenlee and Graham Counties: approximately 27 km (17

mi) along the Gila River, from the confluence with the San Francisco

River downstream to the gaging station in Section 31, Township 6 South,

Range 28 East Meridian.

10. Arizona, Pinal and Graham Counties: approximately 69 km (43 mi)

along the Gila River, from the confluence with the San Pedro River

downstream to the Ashurst-Hayden Dam.

11. Arizona, Graham County: approximately 10 km (6 mi) along Bonita

Creek, from the boundary between Section 36, Township 5 South, Range 27

East, and Section 31, Township 5 South, Range 28 East, downstream to

the confluence of Bonita Creek and the Gila River.

12. Arizona, Maricopa County: approximately 27 km (17 mi) along the

New River, from the boundary between Sections 3 and 4, Township 7

North, Range 3 East, downstream to the boundary between Sections 19 and

20, Township 6 North, Range 2 East.

A total of approximately 467 km (290 mi) of stream and river,

including the 100-year floodplain and 100 meters laterally adjacent to

the 100-year floodplain, is being proposed as critical habitat. The

areas described were chosen for critical habitat designation because

they contain historical and/or current locations for the cactus

ferruginous pygmy-owl, and/or have the potential to support nesting

cactus ferruginous pygmy-owls. All areas contains, or with recovery

will contain, suitable nesting habitat. All areas contain some

unoccupied habitat or former (degraded) habitat, which is needed to

recover ecosystem integrity and support larger numbers of the owl

during its recovery.

The areas proposed for critical habitat are on lands owned and

managed by the Service, the National Park Service, the Bureau of Land

Management, the U.S. Forest Service, the Fort McDowell Indian

Reservation, the Salt River Indian Reservation, the State of Arizona,

and private parties. The majority of proposed critical habitat is on

lands owned or managed by the Bureau of Land Management, the State of

Arizona, and private parties.

The Service is required to base critical habitat proposals on the

best available scientific information (50 CFR Sec. 424.12). In

determining what areas to propose as critical habitat, the Service

considers those physical and biological features that are essential to

the conservation of the species and that may require special management

considerations or protection (primary constituent elements). Species

requirements include, but are not limited to, the following: (1) Space

for individual and population growth; (2) food, water, air, light,

minerals, or other nutritional or physiological requirements; (3) cover

or shelter; (4) sites for breeding, reproduction, rearing of offspring,

germination, or seed dispersal; and, generally, (5) habitats that are

protected from disturbance or are representative of the historical

geographical and ecological distributions of a species. Primary

constituents elements of critical habitat may include, but are not

limited to, the following: Roost sites, nesting grounds, spawning

sites, feeding sites, seasonal wetland or dryland, water quality or

quantity, host species or plant pollinators, geological formation,

vegetation type, tide, and specific soil types.

The Service is proposing to designate as critical habitat areas

which provide, or with rehabilitation will provide, the above physical

and biological features and primary constituent elements. In

determining biologically appropriate areas to propose for designation

as critical habitat, the Service focuses on the primary constituent

elements that are essential to the conservation of the species, without

consideration of land or water ownership or management.

The Service is required to list the primary constituent elements

for any critical habitat that is proposed. For all areas of critical

habitat proposed here, the above features and elements are provided or

will be provided by thickets, forests, woodlands, thornscrub, and

desertscrub that are inhabited or potentially habitable for the primary

biological needs of foraging, nesting, rearing of young, roosting, and

sheltering. Constituent elements include riparian forests, riverbottom

woodlands, and xeroriparian thickets within or bordering the designated

drainages. Woodlands, thickets, and desertscrub associations adjacent

to these floodplain areas also provide primary constituent elements.

Specific plant associations include those dominated by cottonwood,

mesquite, and Sonoran Desertscrub/Thornscrub. These plant associations

are characterized by, but are not limited to, the following plant

species, in any combination: cottonwood, willow (Salix spp.), ash,

mesquite, paloverde, ironwood, saguaro cactus, organpipe cactus,

cresotebush (Larrea spp.), acacia, and hackberry, and areas where such

vegetation may become established. These associations attain their

greatest development, and support the highest numbers of pygmy-owls, in

the approximate 100-year floodplain zone of river drainages.

The presence of surface or subsurface water is critical in

maintaining the majority of pygmy-owl habitat. The thicket, woodland,

and forest communities described above are largely dependent on

availability of groundwater at or near the soil surface. Surface or

subsurface moisture may also be important in maintaining various

species comprising the pygmy-owl's prey base.

The above primary constituent elements are interrelated in the life

history of the cactus ferruginous pygmy-owl. These relationships were

major considerations in selection of proposed critical habitat. In

addition to the above primary constituent elements, several other

selection criteria were used to determine areas necessary for the

survival and recovery of the pygmy-owl. These were: (1) Areas where

pygmy-owls were historically recorded as occurring; (2) areas adjacent

to or near those where pygmy-owls were historically recorded as

occurring that provide or provided the same constituent elements; and

(3) areas pygmy-owls are currently known to occur.

Not all areas likely to have been occupied historically, or likely

to be occupied now, have been proposed for designation as critical

habitat. The critical habitat areas proposed are those that the Service

believes are necessary for the survival and recovery of the pygmy-owl

and in need of special management or protection. For example, in

Sonoran Desertscrub habitat of upland areas in southern Arizona, the

pygmy-owl apparently has always been uncommon to rare and unpredictable

in occurrence. The Service believes this desert habitat has always been

of peripheral or marginal importance to pygmy-owls in Arizona, and that

the habitats necessary for the survival and recovery of the pygmy-owl

are those along major riverbottoms, where the species was historically

common. Therefore, sections of major rivers have been proposed as

critical habitat, but Sonoran Desert habitats, in general, have not.

However, pygmy-owls will still receive protection under Sections 7 and

9 of the Act, regardless of whether they occur in critical habitat.

Designation of critical habitat is not prudent when the species is

threatened by taking or other human activity, and identification of

critical habitat can be expected to increase the degree of such threat,

or when designation of critical habitat would not be beneficial to the

species [50 CFR 424.12(a)(1)].

Because the Service is currently working cooperatively with private

landowners in Texas to reach agreements with them concerning

maintenance of important habitat, the Service has determined that

designation of critical habitat in Texas is unnecessary and would not

be beneficial to the pygmy-owl. Furthermore, a probable outcome of such

a designation in Texas would be an increase in disturbance to pygmy-

owls by bird watchers. An increase in bird watchers trespassing on

private land is a concern expressed by private landowners, and such

events could damage a currently harmonious working relationship with

the Service and researchers.

Section 4(b)(8) requires, for any proposed or final regulation that

designates critical habitat, a brief description and evaluation of

those activities (public or private) that may adversely modify such

habitat or may be affected by such designation. Such activities may

include:

(1) Removing, thinning or destroying vegetation. Activities that

remove, thin, or destroy vegetation, by mechanical (woodcutting or

bulldozing), chemical (herbicides or burning), or biological (grazing)

means;

(2) Water diversion or impoundment, groundwater pumping, or any

other activity that may significantly alter the quantity or quality of

surface or subsurface water flow;

(3) Overstocking or other mismanagement of livestock; and

(4) Development of recreational facilities and off-road vehicle

operation.

Section 4(b)(2) of the Act requires the Service to consider

economic and other impacts of designating a particular area as critical

habitat. The Service will consider the critical habitat designation in

light of all additional relevant information obtained before making a

decision on whether to issue a final rule.

Special Rule

The Service recognizes that the major portion of the population in

Texas exists because present land management by private landowners is

generally compatible with the well-being of the owl. The Service

intends to work with landowners in developing management plans and

agreements with the objective of recovery and eventual delisting of the

Texas population. The Service is also proposing a special rule under

section 4(d) of the Act that offers additional management flexibility

for this species. The special rule would remove the prohibition against

incidental taking of this species in any area subject to a conservation

agreement between the Service and the landowner when the taking is

caused by routine ranching activities and does not involve any

destruction of nest trees. In order for a conservation agreement to be

accepted by the Service, it would have to describe the activities to be

undertaken in the area that may affect the species; estimate the amount

extent, and type of incidental taking likely to result from these

activities; and prescribe adequate mitigation measures.

The Service believes that a special rule of this nature will

benefit the cactus ferruginous pygmy-owl in Texas, and that the rule

would satisfy the requirement under section 4(d) that regulations

applied to threatened species embody those measures deemed necessary

and advisable to provide for the conservation of the species in

question.

Available Conservation Measures

Conservation measures provided to species listed as endangered or

threatened under the Act include recognition, recovery actions,

requirements for Federal protection, and prohibitions against certain

practices. Recognition through listing encourages and results in

conservation actions by Federal, State, and private agencies, groups,

and individuals. The Act provides for possible land acquisition and

cooperation with the States and authorizes recovery plans for all

listed species. The protection required for Federal agencies and the

prohibitions against taking and harm are discussed, in part, below.

Section 7(a) of the Act, as amended, requires Federal agencies 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 being designated. Regulations implementing this

interagency cooperation provision of the Act are codified at 50 CFR

Part 402. Section 7(a)(4) requires Federal agencies to confer

informally with the Service 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. If a species is

listed subsequently, 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 must enter into formal consultation with the Service.

The Act and implementing regulations found at 50 CFR 17.21 and

17.31 set forth a series of general prohibitions and exceptions that

apply to all endangered and threatened wildlife, respectively. These

prohibitions, in part, make it illegal for any person subject to the

jurisdiction of the U.S. to take (includes harass, harm, pursue, hunt,

shoot, wound, kill, trap, or collect; or to attempt any of these),

import or export, ship in interstate commerce in the course of

commercial activity, or sell or offer for sale in interstate or foreign

commerce any listed species. It also is illegal to possess, sell,

deliver, carry, transport, or ship any such wildlife that has been

taken illegally. Certain exceptions apply to agents of the Service and

State conservation agencies.

Permits may be issued to carry out otherwise prohibited activities

involving endangered and threatened wildlife species under certain

circumstances. Regulations governing permits are at 50 CFR 17.22,

17.23, and 17.32. Such permits are available for scientific purposes,

to enhance the propagation or survival of the species, and/or for

incidental take in connection with otherwise lawful activities. For

threatened species, there are also permits for zoological exhibition,

educational purposes, or special purposes consistent with the purpose

of the Act.

Section 4(d) of the Act provides authority for the Service to

promulgate special rules for threatened species. The Service is

proposing a special rule for the cactus ferruginous pygmy-owl in Texas

that would relax the prohibition against incidental taking where the

Service and a landowner have entered into a conservation agreement.

Public Comments Solicited

The Service intends that any final action resulting from this

proposal will be as accurate and as effective as possible. Therefore,

comments or suggestions from the public, other concerned governmental

agencies, the scientific community, industry, or any other interested

party concerning this proposed rule are hereby solicited. Comments

particularly are sought concerning:

(1) Biological, commercial trade, or other relevant data concerning

any threat (or lack thereof) to this species;

(2) The location of any additional populations of this species and

the reasons why any habitat should or should not be determined to be

critical habitat as provided by Section 4 of the Act;

(3) Additional information concerning the range, distribution, and

population size of this species;

(4) Current or planned activities in the subject area and their

possible impacts on this species; and

(5) Any foreseeable economic and other impacts resulting from the

proposed designation of critical habitat.

Final promulgation of a regulation on this species will take into

consideration the comments and any additional information received by

the Service, and such communications may lead to a final regulation

that differs from this proposal.

The Endangered Species Act provides for a public hearing on this

proposal, if requested. Requests must be received within 45 days of the

date of publication of this proposal; such requests must be made in

writing and addressed to the Service's Arizona State Office (see

ADDRESSES section).

National Environmental Policy Act

The Fish and Wildlife Service has determined that an Environmental

Assessment, as defined under the authority of the National

Environmental Policy Act of 1969, need not be prepared in connection

with regulations adopted pursuant to Section 4(a) of the Endangered

Species Act of 1973, as amended. A notice outlining the Service's

reasons for this determination was published in the Federal Register on

October 25, 1993 (48 FR 49244).

References Cited

A complete list of all references cited herein is available from

the Service's Arizona State Office (see ADDRESSES).

Author

The primary author of this proposed rule is Robert M. Marshall,

Arizona Ecological Services State Office (see ADDRESSES) above.

List of Subjects in 50 CFR Part 17

Endangered and threatened species, Exports, Imports, Reporting and

recordkeeping requirements, and Transportation.

Proposed Regulation Promulgation

Accordingly, the Service hereby proposes to amend part 17,

subchapter B of chapter I, title 50 of the Code of Federal Regulations,

as set forth below:

PART 17--[AMENDED]

1. The authority citation for Part 17 continues to read as follows:

Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.

4201-4245; Pub. L. 99-625, Stat. 3500; unless otherwise noted.

2. Section 17.11(h) is amended by adding the following, in

alphabetical order under Birds, to the list of Endangered and

Threatened Wildlife, to read as follows:

Sec. 17.11 Endangered and threatened wildlife.

* * * * *

(h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------

Species Vertebrate

---------------------------------------------------------- population

where Critical Special

Historic range endangered Status When listed habitat rules

Common name Scientific name or

threatened

--------------------------------------------------------------------------------------------------------------------------------------------------------

* * * * * * *

Birds

* * * * * * *

Pygmy-owl, cactus Glaucidium brasilianum U.S.A. (AZ, TX), Mexico.... AZ E ........... 17.95(b) NA

ferruginous. cactorum.

* * * * * * *

Do.......................... do......................... do......................... TX T ........... NA 17.41(c)

* * * * * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------

3. Section 17.41 is amended by adding paragraph (c) to read as

follows:

Sec. 17.41 Special rules--birds.

* * * * *

(c) Cactus ferruginous pygmy-owl (Glaucidium brasiliarum cactorum).

(1) Except as noted in paragraph (c)(2) of this section, all

prohibitions of Sec. 17.31 (a) and (b) shall apply to the cactus

ferruginous pygmy-owl in Texas.

(2) Incidental take of the cactus ferruginous pygmy-owl will not be

a violation of section 9 of the Endangered Species Act of 1973, as

amended, if it results from routine ranching operations, such as

fencing and road building or maintenance, provided that:

(i) No nest trees are destroyed.

(ii) The owner of the land upon which the incidental take occurs

and the Service have signed a conservation agreement that provides for

the persistence of essential habitat features for the cactus

ferruginous pygmy-owl. The conservation agreement must include, at

minimum:

(A) A description of activities that may affect the cactus

ferruginous pygmy-owl.

(B) An estimate of the amount, extent, and type of incidental

taking that may result from these activities.

(C) A description of any mitigation measures, such as seasonal

restrictions or protection of nests groves, that will be carried out to

minimize impact to and taking of cactus ferruginous pygmy-owls.

(iii) The operations that may affect the cactus ferruginous pygmy-

owl are in compliance with all other Federal and State laws that

provide protection for the cactus ferruginous pygmy-owl.

4. Section 17.95(b) is amended by adding critical habitat of the

cactus ferruginous pygmy-owl, in the same alphabetical order as the

species occurs in Sec. 17.11(h), to read as follows:

Sec. 17.95 Critical habitat--Fish and wildlife.

* * * * *

(b) * * *

* * * * *

Cactus Ferruginous Pygmy-Owl (Glaucidium brasilianum cactorum)

Arizona. Areas of land and water as follows (all legal descriptions

are from the Gila and Salt River Meridian):

1. Maricopa County: Salt River, from Stewart Mountain Dam (T3N,

R8E, Section 33) downstream to Granite Reef Dam (T2N, R7E, Section 5).

The boundaries include the current active channel(s), and all

secondary, side, and overflow channels, up to and including the 100-

year floodplain, and areas within 100 m (328 ft) laterally adjacent to

the 100-year floodplain.

2. Maricopa County: Verde River, from Bartlett Dam (T4N, R7E,

Section 33) downstream to the confluence of the Verde and Salt Rivers

(T2N, R7E, Section 5). The boundaries include the current active

channel(s), and all secondary, side, and overflow channels, up to and

including the 100-year floodplain, and areas within 100 m (328 ft)

laterally adjacent to the 100 year-floodplain.

3. Cochise, Pima, and Pinal Counties: San Pedro River, from the

confluence of Soza Canyon (T12S, R19E, Section 30) downstream to the

confluence of the San Pedro and Gila Rivers (T5S, R15E, Section 23),

including Cook's Lake. The boundaries include the current active

channel(s), and all secondary, side, and overflow channels, up to and

including the 100-year floodplain, and areas within 100 meters (328

feet) laterally adjacent to the 100-year floodplain.

4. Pima County: Santa Cruz River, from the Interstate 19 bridge

(T15S, R13E, Section 26) downstream to the Avra Valley Road bridge

(T12S, R12E, Section 8). The boundaries include the current active

channel(s), and all secondary, side, and overflow channels, up to and

including the 100-year floodplain, and areas within 100 meters (328 ft)

laterally adjacent to the 100-year floodplain.

5. Pima County: Rillito Creek system, from the confluence of

Rillito Creek and the Santa Cruz River (T13S, R13E, Section 7)

upstream, along Tanque Verde Creek to the boundary between Sections 2

and 3, T14S, R16E, and upstream along Agua Caliente Creek to the

Soldier Trail crossing (T13S, R16E, Section 19). The boundaries include

the current active channel(s), and all secondary, side, and overflow

channels, up to and including the 100-year floodplain, and areas within

100 m (328 ft) laterally adjacent to the 100-year floodplain.

6. Pima County: Canada del Oro, from its confluence with Sutherland

Wash (T11S, R14E, Section 4) downstream to its confluence with the

Santa Cruz River (T13S, R12E, Section 1). The boundaries include the

current active channel(s), and all secondary, side, and overflow

channels, up to and including the 100-year floodplain, and areas within

100 meters (328 feet) laterally adjacent to the 100-year floodplain.

7. Pima County: Alamo/Growler Wash system, from the well in Alamo

Canyon (T16S, R4W, unsurveyed Section 6) downstream to the point where

Growler Wash intersects the Bates Well road (T15S, R7W, Section 6). The

boundaries include the current active channel(s), and all secondary,

side, and overflow channels, up to and including the 100-year

floodplain, and areas within 100 m (328 ft) laterally adjacent to the

100-year floodplain.

8. Pima County: Arivaca Creek, from the road crossing in the town

of Arivaca (T21S, R10E, Section 28) downstream to the confluence with

San Luis Wash (T21S, R9E, Section 4). The boundaries include the

current active channel(s), and all secondary, side, and overflow

channels, up to and including the 100-year floodplain, and areas within

100 m (328 ft) laterally adjacent to the 100-year floodplain.

9. Greenlee and Graham Counties: Gila River, from the confluence

with the San Francisco River (T5S, R29E, Section 28) downstream to the

gaging station in Section 31, T6S, R28E. The boundaries include the

current active channel(s), and all secondary, side, and overflow

channels, up to and including the 100-year floodplain, and areas within

100 m (328 ft) laterally adjacent to the 100-year floodplain.

10. Pinal and Graham Counties: Gila River, from the confluence with

the San Pedro River (T5S, R15E, Section 23) downstream to the Ashurst-

Hayden Dam (T4S, R11E, Section 8). The boundaries include the current

active channel(s), and all secondary, side, and overflow channels, up

to and including the 100-year floodplain, and areas within 100 m (328

ft) laterally adjacent to the 100-year floodplain.

11. Graham County: Bonita Creek, from the boundary between Section

36 (T5S, R27E) and Section 31 (T5S, R28E) downstream to the confluence

of Bonita Creek and the Gila River (T6S, R28E, Section 21). The

boundaries include the current active channel(s), and all secondary,

side, and overflow channels, up to and including the 100-year

floodplain, and areas within 100 m (328 ft) laterally adjacent to the

100-year floodplain.

12. Maricopa County: New River, from the boundary between Sections

3 and 4, Township 7 North, Range 3 East, downstream to the boundary

between Sections 19 and 20, Township 6 North, Range 2 East. The

boundaries include the current active channel(s), and all secondary,

side, and overflow channels, up to and including the 100-year

floodplain, and areas within 100 m (328 ft) laterally adjacent to the

100-year floodplain.

The primary constituent elements of cactus ferruginous pygmy owl

critical habitat include: Sonoran Desertscrub, xeroriparian thickets,

riparian thickets, forests, and woodlands, and areas where such

vegetation does not currently exist but may become established with

natural regeneration or habitat rehabilitation.

Note: Map follows:

BILLING CODE 4310-55-M

TP12DE94.002

BILLING CODE 4310-55-C

Dated: December 6, 1994.

George T. Frampton, Jr.,

Assistant Secretary for Fish and Wildlife and Parks.

[FR Doc. 94-30468 Filed 12-7-94; 1:27 pm]

BILLING CODE 4310-55-M