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LARGE SANDHILL CRANES WINTERING IN CALIFORNIA 277 l! 1
<br /> tral Valley during the winter of 1983-1984 and
<br /> southerly staging and wintering areas(U.S.F.W.S.
<br /> the 3,200-3,400 cranes known to spend the sum- 1982b). Unfortunately, the post-breeding move-
<br /> mer in Oregon and California (Stern et al. 1987, ments of specific nesting subpopulations of cranes
<br /> Littlefield 1989) provides an estimate of the from the Pacific States and British Columbia are
<br /> lumber of Sandhill Cranes that spend the breed- poorly known, as is the nesting distribution of
<br /> ing season in British Columbia, where the num- cranes in British Columbia. Color-marking, ra-
<br /> ')er of cranes has been stated to be only 600 dio-tagging, and monitoring cranes of known
<br /> 'U.S.F.W.S. 1983). Thus, between 2,600-3,600 breeding origin will be necessary to describe the j
<br /> cranes from British Columbia are wintering in migration routes, spring and fall staging areas,
<br /> ,he Central Valley and mixing with the cranes and wintering-areas of cranes from specific breed-
<br /> vhich spend the breeding season in Oregon and ing subpopulations. Studies of cranes in British
<br /> California. Hypothetically, an increase in the Columbia and a marking program throughout
<br /> number of cranes from British Columbia could the population's breeding range are needed be-
<br /> tlso have contributed to the increased number fore estimates of production and population size
<br /> ,-af cranes we found in the Central Valley in the for specific breeding populations can be imple-
<br /> 1983-1984 winter. mented at wintering areas.
<br /> tAC1AL COMPOSITION OF THE POPULATION ACKNOWLEDGMENTS
<br /> The Sandhill Cranes nesting on the coast of Brit-
<br /> Dozens of individuals contributed to the completion
<br /> sh Columbia(Fig. 3)are intermediate-sized birds of this study. We appreciate the assistance of the 77
<br /> a the size range of Canadian Sandhill Cranes, respondents to our questionnaire survey. Without the
<br /> G. c. rowans, and available data suggest the cranes kindness and hospitality from the farmers and water-
<br /> 'rom the interior of the province are Greater fowl hunters of California's Central Valley(B. Darsie,
<br /> G. and M. Meyers, I. N. Robinson, J. Shanks, K. P.
<br /> andhill Cranes. Cranes from interior and coast- and R.Shea,and many others),who kindly allowed us
<br /> al British Columbia use different migration routes, access to their property, provided housing,and shared
<br /> although cranes from both breeding areas winter their knowledge of cranes and of the Central Valley,
<br /> i the Central Valley(Littlefield and Thompson, the study would not have been possible. C. D. Little-
<br /> .979, U.S.F.W.S. 1983). The largest number of field M. Stern, C. Bloom, and personnel of Malheur
<br /> NWR, Modoc NWR, and The Nature Conservancy's
<br /> intermediate-sized cranes counted at wintering Oregon Field Office eagerly shared their crane banding
<br /> seas was only 258 (T. Pogson, unpubl. data), records with us and this greatly enhanced the study.
<br /> ut 893 intermediate-sized cranes were counted R. Schlorff, J. Snowden, E. Nies,J. Dixon, B. Orange,
<br /> at a spring staging area for cranes using the coast- and other members of the California Department of
<br /> Fish and Game; and D. Bauer, D. Gilmer, G. Zahm,
<br /> 1 migration route on Sauvies Island north of F. Milton, E. Nelson, G. Mensik, C.Smith, and other
<br /> ortland, Oregon, in 1982 (T. Pogson, unpubl. members of the U.S. Fish and Wildlife Service pro- {`s
<br /> data). Thus, our estimates of the Central Valley vided essential logistical support and information on ; !
<br /> -opulation's size could have included as many crane distribution. The Dixon Field Station of the ;,t
<br /> 3 893 intermediate-sized cranes from coastal U.S.F,W.S.'s Northern Prairie Wildlife Research Cen-
<br /> ter provided telemetry equipment.S.A.M. Benitez and j
<br /> g R. J. Pogson provided essential logistic support. G.
<br /> Winter surveys were valuable for identifying Kaiser and N. K. Dawe of the Canadian Wildlife Ser- { a
<br /> nportant wintering sites for the protection and vice, R. W. Campbell and M. McNall of the Royal s� `
<br /> British Columbia Museum,R.J.Cannings of the Uni- `' i
<br /> acquisition of habitat to the Central Valley. versity of British Columbia,H.Ouellet of the National
<br /> However, because cranes from different breeding Museum of Canada, and R. Howie graciously shared
<br /> tinges appeared to be mixing at wintering areas, information on cranes in British Columbia. B. Ander- k HT1
<br /> -inter surveys were not useful for estimating the son provided data on cranes migrating through western rik-
<br /> -.)n,
<br /> abundance and productivity of specific breeding Washington. The study was funded (in pan) by the�bpopulations of cranes from California, Ore- University of Alaska's John F. Marooney MemorialScholarship, and the U.S. Fish and Wildlife Service's and British Columbia.Alternatively,it would Office of Migratory Bird Management in Portland,Or-
<br /> be useful to census the population and obtain egon(P.O. 10181-87-70593,BW).We owe special gnat- "
<br /> ;timates of productivity on the breeding grounds itude to C. D. Littlefield and M.Stem for sharing many
<br /> tern et al. 1987, Littlefield 1989), or at staging hours of discussion on cranes, their encouragement,
<br /> and review of the manuscript. J. S. Sedinger, S. F.
<br /> areas in the fall where cranes from particular MacLean, Jr., E. C. Murphy, and P. Flint provided
<br /> .sting areas concentrate before moving to more many useful comments on drafts of the manuscript.
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