Welcome to the Midwinter Bald Eagle Count Web Site!

Overview

This site provides access to results of Midwinter Bald Eagle Surveys conducted from 1986-2005 along 746 routes in 43 states. You can retrieve raw count data as well as summary information (trends, means, high and low counts) for survey routes using the buttons at the top of the page. You can obtain model-based estimates of trends for different regions and states by clicking on Summary Trend Information on the left sidebar.

The buttons at the top of the page allow you to search for survey routes by state, map location, drainage/survey route name, or geographic coordinates (latitude and longitude). You can retrieve summaries for one route at a time or for multiple routes. An interactive help program will walk you through the steps (How to Use This Site).

The Midwinter Bald Eagle Survey takes place during the first two weeks of January each year. The U.S. Army Corps of Engineers (USACE) coordinates the Midwinter Bald Eagle Survey, in which several hundred individuals count eagles along standard, non-overlapping survey routes. For more details on the history of the count, see Background/History of the Survey.

The data available from this website were used in an analysis of count trends from 1986-2005. This 20-year analysis used the same methods used in a peer-reviewed 15-year trend analysis (Steenhof, K., L. Bond, K.K. Bates and L.L. Leppert. 2002. Trends in midwinter counts of Bald eagles in the contiguous United States, 1986-2000. Bird Populations 6:21-32). The extended analysis did not receive additional peer review because of this consistency. Please note that data from routes that were not surveyed consistently for at least four years and routes that never had more than three eagle observations in a single year during the 20-year sampling period were not used in the trend analysis and are not available from this website.

Citation Information

Please cite this Page as: Steenhof, K., L. Bond, and L. L. Dunn. 2008. The midwinter bald eagle survey results and analysis 1986-2005. U.S.Geological Survey, National Biological Information Infrastructure, and Northwest Alliance for Computational Science and Engineering. Available on-line at http://www.nacse.org/nbii/eagles. (Indicate access date.)