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Paul D. Jorgensen

Publications and source records attributed to Paul D. Jorgensen.

2 recordsLinked to original sources

Birds of the northcentral Alaska Peninsula, 1976-1980

Between spring 1976 and fall 1980 we studied the occurrence, abundance, and habitat use of birds over a 2000 square km segment of the northcentral Alaska Peninsula. During this period observers were present 473 days and obtained records for all seasons. A total of 125 species was recorded; 63% (79 of 125) were water-associated. The breeding avifauna was found to be a mixture of Panboreal (49%), North American (34%), and Aleutican (17%) species. The Aleutican group was dominant in terms of biomass and numbers of individuals during the nonbreeding period. Forty-two species were confirmed breeding in the area and another 19 were suspected of breeding. The majority of birds occurred as migrants; 14 species were considered permanent residents and an additional 20 were winter residents. ... The area is a principal late summer and fall molting and staging area for several species of arctic and subarctic nesting waders and seaducks and emperor geese .... From late September through mid-October the density of water birds over the entire littoral and nearshore area approached 1000 birds square km. This density was exceeded many fold for certain species on particular segments of habitats in the area.

Alaska

The light-footed clapper rail: An update

A preliminary report on the Light-footed Clapper Rail, Rallus longirostris levipes , estimated a population of 500-750 birds in California (Wilbur, Am. Birds 28:868-870, 1974). Since then, additional work has been accomplished, most notably: (1) an intensive study of Carpinteria Marsh, Santa Barbara County, 1976-1977 (Basham); (2) a series of winter high tide counts at Anaheim Bay, Orange County, 1975-1977 (Massey, C. Collins, J. Lindell, M. Silbernagle); and (3) a detailed investigation of the rail population of Tijuana Slough, San Diego County, 1973-1974 (Jorgensen). These, plus short-term studies by the authors and K. Bender, D. Pinkler, P. Johns, and S. Lockhart, have shown that the original estimate was unrealistic. A more probable winter total is 300 rails, distributed as described below.

California