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ARS Home » Southeast Area » Stuttgart, Arkansas » Harry K. Dupree Stuttgart National Aquaculture Research Cntr » Research » Publications at this Location » Publication #153087
Title: LACKING SCIENTIFIC DATA FOR DOUBLE-CRESTED CORMORANTS - THE NEED TO REVITALIZE A BANDING PROGRAM

Author
item Radomski, Andrew

Submitted to: Inland Bird Banding Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/2003
Publication Date: 8/15/2003
Citation: Radomski, A.A. 2003. Lacking scientific data for double-crested cormorants - the need to revitalize a banding program [abstract]. Inland Bird Banding Meeting Abstracts. p. 3.

Interpretive Summary:

Technical Abstract: Increasing numbers of Double-crested Cormorants (Phalacrocorax auritus) at commercial aquaculture production facilities have resulted in biological, economical, and social conflicts. This is one of the arguments made by the U.S. Fish and Wildlife Service for the creation of a National Management Plan for this species. However, only a few states census cormorants and fewer states are banding. This may lead to inaccurate assessments of an implemented plan. Therefore, the USDA-ARS has initiated and conducted aerial surveys by fixed-wing aircraft to monitor and quantify the wintering cormorant numbers from 1999-2003 and has plans to initiate a banding program. Aerial surveys were conducted during the last 3 hours of sunlight and encompassed the primary catfish production areas in Arkansas. Aerial counts were validated with ground observations the following morning at specific roosts for accuracy. A minimum of 16,000 cormorants was observed during each survey, with the exception of early January 2000 and 2001. Cormorant numbers peaked (>26,000) in early February 2001 and a total of 12 to 15 night roost sites were monitored during 1999-2003. Cormorants roosted in bald cypress trees almost exclusively. Some roosts were protected from human disturbances, but some were adjacent to highways or adjacent to high recreational areas. Similarities in numbers of cormorants counted in the evening by aircraft and the following morning by ground observers at the same roost allows for increased confidence that the estimates are reasonably accurate. It is important to monitor cormorants and reestablish a banding program to better understand the population trends, movements during the winter, roost site selection, roosting behavior, and changes that may occur with a national management plan.