Washington, DC: Office of Biological Services, 1989. — 28 p.We describe shipboard and small boat techniques used by the U.S. Fish and Wildlife Service in Alaska to survey marine birds at sea. The basis is a 10-min, 300-m-wide, strip transect taken from a platform moving at a constant speed in a constant direction. Special routines, such as instantaneous counts of traveling birds, are explained to help reduce biases caused by factors such as varying flight patterns, ship-following and avoidance, and patchy distributions. Data recording and coding techniques and formats, based on those developed for the National Oceanic Data Center, are described.
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