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Home , Dendragapus, Dusky grouse, Mount Pinos, Sooty grouse

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Species Accounts

Andy Birch

PDF of Mount Pinos Sooty account from: Shuford, W. D., and Gardali, T., editors. 2008. Species of Special Concern: A ranked assessment of species, subspecies, and distinct populations of of immediate conservation concern in California. Studies of Western Birds 1. Western Field Ornithologists, Camarillo, California, and California Department of Fish and Game, Sacramento. Studies of Western Birds No. 1

MOUNT PINOS ( fuliginosus howardi) James D. Bland

Criteria Scores Population Trend 10 Range Trend 5 Population Size 7.5 Range Size 10 Endemism 10 Population Concentration 0 Threats 5

Current Year-round Range Historic Year-round Range County Boundaries Water Bodies

Kilometers 80 40 0 80

Current and historic (ca. 1944) year-round range of the Mount Pinos Sooty Grouse. Restricted to the southern south of Kings Canyon and now extirpated or quasi-extirpated from isolated ranges to the south (Piute and Tehachapi mountains, Mt. Pinos area). Still numerous in northern portion of range but overall numbers have declined moderately.

102 Studies of Western Birds 1:102–106, 2008 Species Accounts California Bird Species of Special Concern

Special Concern Priority Historic Range and Abundance Currently considered a Bird Species of Special in California Concern (year round), priority 2. Not included on Grinnell and Miller (1944) considered the sub- prior special concern lists (Remsen 1978, CDFG species “locally common” in suitable parts of the 1992). main southern Sierra Nevada but “sparse” on the montane islands at the southwestern limit of its Breeding Bird Survey Statistics range. Specimens and eggs collected in the early for California 20th century confirmed Sooty Grouse in the Piute Mountains, Tehachapi Mountains, the Mount Data inadequate for trend assessment (Sauer et Pinos/Mount Able (Cerro Noroestre) area, and al. 2005). (Willet 1933, Grinnell and Miller 1944). A single report of “two chicks” origi- General Range and Abundance nated from Big Mountain, Santa Barbara Two groups of the former Blue Grouse (Dendragapus County, in 1938 (Lentz 1993), but, given the obscurus) were recently recognized as separate spe- limited details available, this record is best consid- cies, the (D. obscurus) and the ered hypothetical (Lehman 1994). Most southern Sooty Grouse (D. fuliginosus; Banks et al. 2006). records originated from Mount Pinos, where in The Sooty Grouse, comprising four subspecies, 1928 the egg collector J. R. Pemberton estimated is endemic to western North America. It resides there to be no more than 50 pairs (WFVZ egg on the western slopes of the coastal mountains data slip). Grinnell and Miller (1944) indicated of British Columbia and southeastern Alaska Sooty Grouse had become “very scarce” on Mount (including most adjacent islands) and in the Pinos by the early 1940s. major cordilleras of western Washington, west- ern Oregon, and northern and central (formerly Recent Range and Abundance southern) California, often as disjunct populations in California in outlier ranges (Zwickel and Bendell 2004). In California, it occurs in the northern Coast Ranges The Mount Pinos Sooty Grouse appears to be (south to Sonoma Co.) and in the Klamath and extirpated or nearly extirpated from the habitat Siskiyou mountains south through the Cascade “islands” that make up the southern portion and Sierra Nevada ranges, with outlying popula- of its range (Bland 2004; see map). It is locally tions in nearby mountains to the east and (for- abundant in the northern portion of its range, but merly) south (Grinnell and Miller 1944). Three becomes increasingly rare toward the southern subspecies are recognized in California. Although limit of contiguous in the southern Sierra their geographic and genetic delineations have Nevada. not been subjected to modern analytical tech- Densities at the northern limit of the subspe- niques, a mitochondrial DNA–based study is cur- cies’ range are the highest Sooty Grouse densities rently underway (G. Barrowclough pers. comm.). recorded anywhere in California. High densities Historically, the Mount Pinos Sooty Grouse (D. f. were first noted in this area in the late 1970s (F. Zwickel pers. comm.). In 1992, densities of hoot- howardi), the southernmost of these, inhabited the 2 southern Sierra Nevada south of Kings Canyon, ing males were estimated to be 3 males per km the Tehachapi Mountains, and the Mount Pinos at Big Baldy Ridge, Sequoia National Park, Tulare area (Grinnell and Miller 1944). It is most abun- County (J. Bland unpubl. data). Although high by California standards, densities can exceed 130 dant and widespread at the northern limit of its 2 range. Further south, appropriate habitat is limited males per km in the Pacific Northwest (Bendell to montane “islands” where Sooty Grouse histori- and Zwickel 1984). At the periphery of their range cally were scarce and now may be absent. and in heterogeneous habitats, as Sooty Grouse are in the Sierra Nevada, males tend to congregate in “hooting groups” in spring (Bendell and Elliott Seasonal Status in California 1967, Bendell and Zwickel 1984). These groups Occurs year round; breeding season is not known appear to be small and widely dispersed through- in detail, but could extend from late March out the Sierra Nevada (Bland 1993). Bland (1993) through late August, depending on local climate encountered only 14 hooting groups along 104 and weather (Zwickel and Bendell 2004). km of line transects in presumed Sooty Grouse

Mount Pinos Sooty Grouse 103 Studies of Western Birds No. 1 habitat. The number of males in these groups was 1990s, including an August 1992 report from five or less. The abundance of males was lower by a leading authority on the on harvested national forest lands than on nearby avifauna of County (L. Allen in litt.). unharvested national park lands at sites sam- Brief spring surveys (≤2 days) using recorded pled throughout the Sierra Nevada (Bland 1993). female calls failed to detect grouse on Big Pine In Sequoia National Park and Sequoia National Mountain in 1995 or on the north slope of Mount Forest, abundances of Mount Pinos Sooty Grouse Pinos in 1999 (J. Bland unpubl. data). along line transects were 1.5 and 0.5 hooting males The scarcity of recent records from the southern per km, respectively (J. Bland unpubl. data). portion of the subspecies’ range (south of Tulare On the east slope of the Sierra, in Inyo County, County) prompted Bland to conduct surveys in the subspecies is “common” north of the town all accessible habitat patches in the region, during of Bishop, but is generally restricted to isolated the breeding seasons of 2002 through 2005. More canyons further south (T. Heindel pers. comm.). than 200 km of transects were covered, primarily To the west, in Tulare County, its abundance on foot, and recorded female vocalizations were drops off rapidly south of about 36º N latitude employed. No hooting males were heard, however, (B. Barnes pers. comm., J. Bland pers. obs.). and no grouse were flushed (Bland 2004, J. Bland Whether this was true historically, or has resulted unpubl. data). The results of these surveys suggest from extensive clear-cutting and wildfire in recent Mount Pinos Sooty Grouse no longer breeds in decades, remains uncertain because of the pau- more than 10% of its historic range. The results city of observational records from this region. also suggest that Sooty Grouse observed south of Currently, the southernmost known breeding Tulare County in recent decades may have been locations for the subspecies are at Sunday Peak in birds dispersing from a Sierra Nevada source, south-central Tulare County and Sherman Peak in rather than members of a resident breeding popu- southeastern Tulare County (Bland 2004, J. Bland lation. unpubl. data). In recent decades, Sooty Grouse have rarely Ecological Requirements been reported south of the Tulare-Kern county line. The only recent reports of Sooty Grouse in In the Sierra Nevada portion of its range, the the Piute Mountains are from the vicinity of Piute Mount Pinos Sooty Grouse occupies different veg- Peak in 1985 (K. Axelson pers. comm.) and on etation types according to season (Bland 1996). In unspecified dates in the early 1990s (M. Stone spring, grouse congregate near traditional hooting pers. comm.). There are no recent reports of Sooty sites in high-elevation forest. Hooting Grouse from the Tehachapi Mountains (Garrett habitat usually consists of open, mature Abies/ and Dunn 1981, C. Moore pers. comm.), where Pinus forest on or near a ridge between 6000 and public access to potential grouse habitats is very 10,000 ft (1829–3048 m) elevation, in an area limited. where the snowpack melts early. At least a few There have been few recent confirmed records or pine trees with diameters >100 cm are nor- of Sooty Grouse in the vicinity of Mount Pinos. mally present, often in tight clusters of three to six Most are from the northern slopes of Mount trees. Understory vegetation at hooting sites typi- Pinos and adjoining Sawmill Mountain, Grouse cally consists of scattered clumps of woody shrubs, Mountain, and Mount Able, which all support herbs, and grasses (Bland 1993). In certain envi- isolated stands of fir. Fewer have come from ronments, male Sooty Grouse will establish hoot- Frazier Mountain and Tecuya Ridge, which sup- ing sites in shrubland vegetation, usually within port very limited fir forest. Several observations 2 km of a forest edge (Zwickel 1992). The Sierra were reported in the late 1970s (Lentz 1993), but subspecies (D. f. sierrae), for example, has been Bendell and Zwickel (1984) found no evidence observed hooting in pinyon-juniper vegetation (T. of Sooty Grouse in the Pinos/Sawmill/Abel area Heindel pers. comm.) and (Salix) thickets in 1978, and a 1979 U.S. Forest Service survey (J. Bland pers. obs.) in Inyo County. Mount Pinos found no grouse in the broader Mount Pinos or Sooty Grouse occupying the southern island habi- Mount Frazier areas (Weiss 1979). Both of the tats probably made at least some use of surround- latter surveys employed recorded female calls ing shrublands, but all records of hooting Mount in spring. General avifaunal surveys conducted Pinos Sooty Grouse appear to be from Abies/Pinus throughout the area from 1981 to 1993 did not forest. The spring and summer diet of the Sooty detect Sooty Grouse (Lentz 1993). Lentz (1993) Grouse consists of leaves and flowers of herbs; also cited unconfirmed reports from the early leaves, flowers, and berries of shrubs; conifer

104 Species Accounts California Bird Species of Special Concern needles; and invertebrates, including , , the increase in human use of the area” (Weiss and grasshoppers (Zwickel 1992). 1979). Housing and resort developments now Females nest near the hooting territories of planned or underway on private lands through- males. Eggs are normally laid in a shallow scrape, out the Piute, Tehachapi, and Mount Pinos areas usually with overhead cover from a log, shrub, could add significantly to fragmentation and deg- or rock overhang, but occasionally at the base of radation of grouse habitats. While territorial males a large tree with no immediate cover (Zwickel may habituate to humans, human activity may 1992). Soon after hatching, the hen and brood be unacceptable in the vicinity of brood-rearing may move to a nearby meadow, where they have meadows or winter roosting sites. access to water, dense herbaceous cover, and Legal hunting of Sooty Grouse has not been foods. The typical or optimal distance between permitted south of Tulare County since the brood-rearing meadows and hooting sites has not 1950s. Where hunting is permitted, as in the been ascertained for Sierra Nevada conditions. Sierra Nevada portion of the Mount Pinos Sooty Moist meadows are scarce at the southern portion Grouse’s range, the numbers taken are estimated of the subspecies’ range, so broods might also be to be small (CDFG 2004). reared in shrublands or xeric meadows in these It is uncertain why Mount Pinos Sooty Grouse areas. have become nearly, if not entirely, extirpated Winter activities of Sooty Grouse have not from island habitats south of Tulare County. They been studied in California. The presence of winter were present but scarce over much of the area dropping accumulations within hooting terri- through most of the past century (Grinnell and tories at several southern Sierran sites (J. Bland Miller 1944). Over longer periods of time, their unpubl. data) suggests Mount Pinos Sooty Grouse occurrence may have been cyclic or sporadic, in do not move to special wintering locations, as association with climatic patterns more favorable do some populations of Sooty Grouse (Bendell to fir forest. As fir receded to higher eleva- and Zwickel 1984). Wintering Sooty Grouse are tions over the past 10,000 years, isolated patches mostly inactive, often remaining in the canopy of of forest may have become too small to support a cluster of . The foliage provides thermal local populations of Sooty Grouse without regular cover and an ample supply of conifer needles and emigration from Sierra Nevada populations. Their buds, the staple winter diet of the Sooty Grouse dispersal along a series of forest “stepping stones” (Zwickel 1992). in the Piute and Tehachapi mountains may now be limited or prohibited by recent anthropogenic Threats degradation of these habitats.

The principal threat to the Mount Pinos Sooty Management and Research Grouse is probably habitat degradation caused by Recommendations incompatible timber harvest, fire suppression, and livestock grazing practices. Timber harvest that • Improve interagency coordination regard- results in even-aged stands or evenly distributed ing the Sooty Grouse, possibly through an trees may be detrimental to Mount Pinos Sooty interagency working group. Ensure consid- Grouse, as may be selective harvest of large, eration of Sooty Grouse in timber harvest clumped conifers at the perimeter of forest open- plans, grazing allotments, urban develop- ings. Where fires are infrequent, fir stands may ment, and recreation development. become too dense to serve as breeding habitat. • Confirm the subspecific status of the Mount Overly frequent fires may remove too many Pinos Sooty Grouse with modern genetic shrubs from the understory. Heavy livestock graz- techniques. ing in spring probably degrades food and cover at • Map potential habitat patches, focusing on brood-rearing meadows (Mussehl 1963, Zwickel the distribution of fir stands and montane 1972). Soon, the impact of resort and recreation meadows and seeps (see Weiss 1979, Lentz development may also become apparent in the 1993). range of the Mount Pinos Sooty Grouse. In the • Conduct surveys of all potential breeding Pacific Northwest, local Sooty Grouse popula- sites. Participants should have prior Sooty tions have been extirpated by urban and agricul- Grouse experience and follow a standard- tural development (Zwickel 1992). A U.S. Forest ized protocol. Service report suggests “the lack of recent spring • Characterize the topography, vegetation, and sightings on Mount Pinos roughly coincides with juxtaposition of occupied seasonal habitats

Mount Pinos Sooty Grouse 105 Studies of Western Birds No. 1

across the subspecies’ range. Characterize Bland, J. D. 1996. Forest grouse management plan for site conditions where reproduction is rela- California. Unpublished report, Wildl. Mgmt. Div., tively high, in view of improving habitat Calif. Dept. Fish & Game, 1416 Ninth St., Sacra- conditions at less-productive sites. mento, CA 95814. • Conduct studies to assess the status of Bland, J. D. 2004. Surveys for Mount Pinos Blue Grouse, potential grouse habitats in the Piute and spring 2003. Unpublished report, Wildl. Mgmt. Tehachapi mountains and their importance Div., Calif. Dept. Fish & Game, 1416 Ninth St., Sacramento, CA 95814. as dispersal “stepping stones,” the use of harvested and burned forests in the Department of Fish and Game (CDFG). 1992. Bird species of special concern. Unpublished Sierra Nevada, the impact of livestock and list, July 1992, Calif. Dept. Fish & Game, 1416 Ninth recreational activity on nesting and brood- St., Sacramento, CA 95814. rearing, and the desirability and genetic/ California Department of Fish and Game (CDFG). behavioral consequences of translocating 2004. Resident game bird hunting, final environmen- grouse to formerly occupied habitats. tal document. Wildl. Mgmt. Div., Calif. Dept. Fish & Game, 1416 Ninth St., Sacramento, CA 95814. Monitoring Needs Garrett, K., and Dunn, J. 1981. Birds of Southern Cali- Surveys of hooting and brood-rearing areas should fornia: Status and Distribution. Los Angeles Audubon Soc., Los Angeles. be conducted throughout the subspecies’ range every three to five years, following a standardized Grinnell, J., and Miller, A. H. 1944. The distribution of the birds of California. Pac. Coast Avifauna 27. protocol. Surveyors should check as many hooting groups as possible for persistence over time, and Lehman, P. E. 1994. The Birds of Santa Barbara County, California. Vert. Mus., Univ. Calif., Santa Barbara. they should census some in detail to monitor the actual number of males. It also would be valuable Lentz, J. E. 1993. Breeding birds of four isolated moun- tains in Southern California. W. Birds 24:201–234. to conduct brood counts at known brood-rearing sites. Mussehl, T. W. 1963. Blue Grouse brood cover selec- tion and land-use implications. J. Wildl. Mgmt. 27:547–555. Acknowledgments Remsen, J. V., Jr. 1978. Bird species of special concern This account benefited greatly from information pro- in California: An annotated list of declining or vul- vided by L. Allen, K. Axelson, B. Barnes, T. Benson, nerable bird species. Nongame Wildl. Invest., Wildl. T. and J. Heindel, C. Moore, and M. Stone, and from Mgmt. Branch Admin. Rep. 78-1, Calif. Dept. Fish & editorial comments by J. Amsden, S. Blankenship, T. Game, 1416 Ninth St., Sacramento, CA 95814. Keeney, W. D. Shuford, and F. Zwickel. Sauer, J. R., Hines, J. E., and Fallon, J. 2005. The North American Breeding Bird Survey, results and analysis Literature Cited 1966–2004, version 2005.2. USGS Patuxent Wildl. Banks, R. C., Cicero, C., Dunn, J. L., Kratter, A. W., Res. Ctr., Laurel, MD. Available at www.mbr-pwrc. Rasmussen, P. C., Remsen, J. V., Jr., Rising, J. D., and usgs.gov/bbs/bbs.html. Stotz, D. F. 2006. Forty-seventh supplement to the Weiss, S. 1979. Blue Grouse study report. Unpublished American Ornithologists’ Union Check-list of North report, Mount Pinos Ranger District, Los Padres American Birds. Auk 123:926–936. Natl. Forest, 34580 Lockwood Valley Rd, Frazier Bendell, J. F., and Elliott, P. W. 1967. Behavior and the Park, CA 93225. regulation of numbers in Blue Grouse. Report Series Willett, G. 1933. A revised list of the birds of southwest- 4, Can. Wildl. Serv., Ottawa. ern California. Pac. Coast Avifauna 21. Bendell, J. F., and Zwickel, F. C. 1984. A survey of the Zwickel, F. C. 1972. Some effects of grazing on Blue biology, ecology, abundance, and distribution of the Grouse during summer. J. Wildl. Mgmt. 36:631– Blue Grouse, in Proceedings of the Third Interna- 634. tional Grouse Symposium (P. J. Hudson and T. Lovel, Zwickel, F. C. 1992. Blue Grouse (Dendragapus obscu- eds.), pp. 163–192. World Assoc., P.O. Box rus), in the Birds of North America (A. Poole, P. 5, Lower Basildon, Reading, UK RG8 9PF. Stettenheim, and F. Gill, eds.), no. 15. Acad. Nat. Bland, J. D. 1993. Forest grouse and Mountain Quail Sci., Philadelphia. investigations: A final report for work completed dur- Zwickel, F. C., and Bendell, F. J. 2004. Blue Grouse: ing the summer of 1992. Unpublished report, Wildl. Their Biology and Natural History. NRC Res. Press, Mgmt. Div., Calif. Dept. Fish & Game, 1416 Ninth Ottawa. St., Sacramento, CA 95814.

106 Species Accounts