Environmental Impact Research Program. Avian Line-Transect Methods. Section 6.3.2, US Army Corps of Engineers Wildlife Resources Management Manual.

This report on avian line-transect methods is provided as Section 6.3.2 of the US Army Corps of Engineers Wildlife Resources Management Manual. The report is designed to assist the District or project biologist in the application of line-transect methods to estimate the density and diversity of bird populations for planning, management, and research purposes. The basic line-transect survey involves walking a predetermined straight path and recording detections of birds along both sides of the line. The method is best suited to fairly large areas with homogeneous vegetation and gentle terrain, and can be used at any time of year. The report provides guidelines concerning transect establishment, sample size, survey timing and procedures, and interpretation of results, including an explanation and comparison of fixed width transects, Emlens method, and a modified Emlens method.