North American Breeding Bird Survey 2024

Species Group Summaries for Bird Conservation Regions

This analysis will produce a summary of trends. The summary includes:

Link and Sauer, 1996

Link, W. A., and J. R. Sauer. 1996. Extremes in ecology: avoiding the misleading effects of sampling variation in summary analyses. Ecology 77:1633-1640.

Abstract. Surveys such as the North American Breeding Bird Survey (BBS) produce large collections of parameter estimates. One's natural inclination when confronted with lists of parameter estimates is to look for the extreme values: in the BBS, these correspond to the species that appear to have the greatest changes in population size through time. Unfortunately, extreme estimates are liable to correspond to the most poorly estimated parameters. Consequently, the most extreme parameters may not match up with the most extreme parameter estimates. The ranking of parameter values on the basis of their estimates is a difficult statistical problem. We use data from the BBS and simulations to illustrate the potential misleading effects of sampling variation in rankings of parameters. We describe empirical Bayes and constrained empirical Bayes procedures which provide partial solutions to the problem of ranking in the presence of sampling variation.

Key words: Bayes estimation; Breeding Bird Survey; constrained Bayes
estimation; extremes; sampling variation; trend.

We also provide some estimates of mean trend and a ranking of species from most extreme decline to most extreme increase, using the procedures given in . These results adjust estimates for relative precision, and you can estimate:

See Link and Sauer (1996) for the details of estimating the precision-adjusted averages.

These results are based on the Route-regression, estimating equations method.

Please select the data and time period of interest:
1966-2024 core areas
1993-2024 expanded areas

Please enter the Bird Conservation Region of interest:

Please select the guild of interest:

Grassland Breeding Open-cup Nesting Short Distance Migrant
Wetland Breeding Ground or Low nesting Neotropical Migrant
Successional or Scrub Breeding Mid-story or Canopy Nesting Permanent Resident
Woodland Breeding Cavity Nesting
Urban Breeding All Species

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ver 2026-01-08, Authors: J. Hostetler and J.E. Hines.

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