U.S. Department of Agriculture: Animal and Plant Health Inspection Service
United States Department of Agriculture Wildlife Services: Staff Publications
Document Type
Article
Date of this Version
August 1997
Abstract
We evaluated aerial photography (full coverage, using fixed-wing aircraft) and aerial video (transects, using helicopter) surveys to estimate the population of Laughing Gull (Larus ahicilla) nests in Jamaica Bay, New York, during June 1992-1995. We counted 4,920 nests in the colony using aerial photography and estimated 5,367 nests using aerial video in 1992. In 1993-1995, we respectively counted 5,691,5,095, and 6,126 nests in the colony using aerial photography, and estimated from ground plots that our counts differed from the actual number of nests by means of -9% to 1%. Overall (1993-1995) correction factors (by which to multiply the aerial photography nest counts) to estimate the mean and 95% lower and upper CI range of the nest population were 1.04, 0.96 and 1.13, respectively. Ninety-seven percent of nests identified using aerial photography or video had 21 adult Laughing Gull present or within 1 m of the nest. The aerial video survey was less expensive ($2,100 United States currency) than the aerial photography survey ($4,000). The estimated cost of a total count of nests from the ground is $6,700- $9,600. The aerial video survey provided an accurate estimate of the number of nests. Full coverage aerial photography also provided an accurate estimate of nests in addition to habitat, nest distribution and nest density data.