60 



BiitLs — Our Living Ri'stmrces 



For further information: 



Brian A. Harrington 



Manomel Observatory for 



Conservation Sciences 



Manomct. MA 02345 



H;imngton. B A.. J.P. Myers, and J.S. Grear. igSQ. Coastal 

 refueling sites for global bird migrants. Pages 4293-4307 

 ill O.T. Magoon. H. Converse. D.Miner. L.T. Tobin, and 

 D. Clark, eds. Proceedings of the Sixth Symposium on 

 Coastal and Ocean Management. American Society of 

 Civil Engineers, New York, 



Howe, M.A., RH, Geissler, and B.A. HiuTington. 1989. 

 Population trends of North American shorebirds based 

 on the International Shorebird Survey. Biological 

 Conservation 49:185-200. 



Morrison. R.I.G., C. Downes. and B. Collins. 1994. 

 Population trends of shorebirds on fall migration in east- 

 em Canada, 1974-1991. Wilson Bull. 106. In press. 



Morrison, R.I.G., and B,A. Harrington, 1979. Critical 

 shorebird resource,s in James Bay and eastern North 

 America. Pages 498-507 in Transactions of the 44th 

 North American Wildlife and Natural Resources 

 Conference. Wildlife Management Institute, Washington. 

 DC, 



Myers, J.P., R.I.G. Morrison, P.Z. Antas, B.A. Hamngton, 

 T.E. Lovejoy, M. Sallaberry. S.E. Senner, and A. Taiak. 

 1987. Conservation strategy for migratory species. 

 American Scientist 75:19-26. 



Page, G., L.E, Stenzel, W.D. Shuford, and C.R. Bruce. 

 1991 . Distnbution and abundance of the snowy plover on 

 its western North American breeding grounds, .lournal of 

 Field Ornithology 62:245-255. 



Sauer, JR.. and J.B. Bortner. 1991, Population trends from 

 the Amencan woodcock singing-ground survey, 1970- 

 88. Journal of Wildlife Management 55:300-312. 



Schneider, DC. and B.A. Hamngton. 1981. Timing of 

 shorebird migration in relation to prey depletion. Auk 

 98:197-220. 



Senner, S,E., and M.A. Howe. 1984. Conservation of 

 Nearctic shorebirds. Pages 379-421 in J. Burger and B. 

 Olla, eds. Shorebirds: breeding behavior and popula- 

 tions. Plenum Press, New York. 



Western 

 North 

 American 

 Shorebirds 



by 

 Robert E. Gill, Jr. 



Colleen M. Handel 

 National Biological Service 



Gary W. Page 

 Point Reves Bird Obsenatorr 



Slioiebiids are a diverse group that include.s 

 oystercalchers, stilts, avocets. plovers, and 

 sandpipers. They are familiar birds of 

 seashores, mudflats, tundra, and other wetlands. 

 but they also occur in deserts, high mountains, 

 forests, and agricultural fields. Widespread loss 

 and alteration of these habitats, especially wet- 

 lands and grasslands during the past 150 years, 

 coupled with unregulated shooting at the turn of 

 the century, resulted in population declines and 

 range contractions of several species throughout 

 North America, In the western portion of the 

 continent, efforts to monitor the status and 

 trends of shorebirds have been in effect for only 

 the past 15-23 years and for only a few species. 

 Methods exist to monitor population trends for 

 most shorebirds. but only broadscale. interna- 

 tional efforts, relying largely on volunteer help, 

 will accomplish this. 



In this article we address shorebirds primar- 

 ily in western North America, the region west of 

 the Continental Divide from northern Alaska to 

 southern Mexico, The 12 states, a Canadian 

 province and tenitory. and the vvesteiTi portion 

 of Mexico within this region represent about 

 25% of the North American landmass (Fig. I). 

 Western North America includes portions of 

 three broad ecological domains; the Polar 

 Domain, encompassing the tundra and boreal 

 forests that cover most of Greenland. Canada, 

 and Alaska; the Humid Temperate Domain, 

 including the humid midlatitude forests and 

 shrublands within the United States, southern 

 portions of the Canadian prairie provinces, and 

 along the west coast of North America; and the 

 Dry Domain, encompassing the short-grass 

 prairies, sagebrush provinces, and deserts (Fig, 

 I; Bailey 1978. 1989). 



Sources of Data 



We derived seasonal distribution of shore- 

 birds within these ecological domains from 

 numerous sources, mostly range maps in field 

 guides, books, and our familiarity with the birds 

 within the region (AOU 1983; Robbins et al. 

 1983: Hayman et al, 1986; Godfrey 1987; 

 National Geographic Society 1987; Paulson 

 1993), 



No continent-wide protocol exists for moni- 

 toring the status and trends of Noith American 

 shorebirds. Current information has largely 

 been acquired through independent programs 

 sponsored by a combination of federal, state. 

 and private conservation agencies. Efforts have 

 mostly been regional, including broadscale 

 monitoring directed primarily at birds during 

 the nonbreeding season (Howe et al, 1989; Gill 

 and Handel 1990; Page et al, 1992: Skagen and 

 Knopf 1993; Momson et al, 1994) or have 

 focused on individual species (Handel and Dau 

 1988; Gill et al, 1991; Page et al 1991: Haig 

 1992: Handel and Gill 1992a: Knopf 1994; RL. 

 Knopf, USFWS, unpublished report). We have 

 relied primarily on this information and that of 

 our ongoing studies to summarize the status and 

 trends of shorebirds in western North America, 



Shorebirds of the Region 



Breeding 



Among the 5 1 species that regularly breed in 

 North America. 47 (92%) do so within western 

 North America (Table), Within this region, the 

 Polar Domain supports the greatest number of 

 breeding species (37), including 5 that breed 

 nowhere else on the continent. The Humid 



