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Loggerhead Shrike Background Tha Loggerhead Shrike (Laniue ludovicianue) is elassilied by the 0. S. Gish and Wildlife Service (Fedora Register 11, Nmr. 21, 1991) ae Category 2, "rasa for vhleh information mr in the possession of the Service indicates that proposing co lief ae endangered or thzeateaad is poaaibly appropriate. but Por rhieh conclusive data on biological vulnerability sad threat are not durrently available to support proposed rules." Killer [8yeeematic revision and natural history o! the American shrikes (Lanius). Univ. Calif. Publ. Zool. 38:11-242. 1931.] gives the habitat for t~fifie rasa occurring in reaeern Colorado a• the Artamisia (eagebrumh) association. Andrew and Higheer (Colorado Birds, 1 give the habitat as "Open riparian areas. agricultural areas, grass ands, and ehru6lande, eapeeiaiiy aemidasert ehrublande, and somatime• open pinon-juniper roodlands. Breeding birds are usually near isolated trees or large ehrube. Primarily greaearood draw in both sower and rimer in Maea County (8. Lambeth and 1. Levad, pers. comm.) and probably elearhare in reatern Colorado." They give the status as "paisly cowon sv>.er resident is eeseern valleys.... Rare to uncommon is mouate7.a parks sad rare in mouataiae, mosely in lows mountains.... There are no confirmed breeding records in the mountain parks ... or mountains." l~ifiestie~ne of Invmseigator The principal investigator, Robezt Dora, hoe a K. S. in Fish and Wildlife l4ASgment lrom Montana State University. 8e is co-author of ~ ominj Birds and author of sevsrai seieatifle papers on rildlife including birds. 8e hoe nearly 30 years asperimnee rith Rocky Mountain rildlife and has conducted nuaerous surveya for threatened and endangered animals and for "migratory birds of high lederal interest." Busve Methods Approximately 40 acres in T13S g90W parts of Sections 9, 10, 15, and 16, Gunnison County, Colorado (Map 1), rere surveyed on foot on Kay 9, 1994, by Robert Dorn. Tha survey included several hundred Yeet oueside the proposed disturbance areas. The general habieats rere noted and all birds seen or heard incidental to a vegetation survey more recorded. Burve Reeulte The area ie mostly covered rith oak-earviceberry-chokecherry brush rich none open grassy parka, grassy disturbed areas, storage and facilisie^ areas, sad a fer roads. The folloring birds more observed or heard: Turkey Vulture, Bad-shafeed Flicker, Broad-tailed Eummiagbird, 9eeller'e Jay, Black-capped Chieksdee, Hlue-gray fimtcacchmr, Mountain Bluebird, Tor:uand'a Solitaire, American Robin, Audubon's Warbler, Rufous-raided Torhee, and 8rerer'm Blackbird. The Buloue-sided Torhe• ras by far the moat abundant species reflecting the extensive cover of denss shrubs. Conclusions No Loggerhead Shrikes rere observed in the ^urvey area. The area ie extremely marginal habitat for this species because aF she dense, tall shrub cover. Bhrikea are birds of open, dry country, found most commonly in seaideeett and grassland areas there there era relatively fer, scattered, large ehrube or trees. In wstezn Colorado ehey are moat frequently esan in gresearood or basin big sagebrush habita[e and rarely in mountain sites under vhieh latter eaeagory the survey aren mould fall. 3