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North American Breeding Bird Survey

Species Group Summaries


Select a time period, region, and species group, and this program will produce a summary of trends. The summary includes:
1966 - 2010 Analysis
See the BBS Summary and Analysis Website for citation, version number, and cautions regarding use.

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 Link and Sauer 1996. 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. We note that more sophistical methods for these summaries now exist (e.g., hierarchical models for group summaries, Sauer and Link 2002a). We are in the process of implementing these analyses, and they should be available in future summaries.

These results are based on hierarchical model trend estimates (Link and Sauer 2002).

We group birds based on attributes such as breeding habitat, nest type, migration status, and nest location. If species in the group show consistent trends, and differ from species not in the groups, it suggests that the common feature could be influencing population change for the group. For more discussion on this, click here. For a listing of the species in each guild, click here





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ver 2010.0, 2 December 2011, Authors: J. R. Sauer and J. E. Hines.

BRD Data Liability Disclaimer

Although these data have been processed successfully on a computer system at the USGS Biological Resource Division, no warranty expressed or implied is made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is strongly recommended that these data are directly acquired from a Biological Resource Division server, and not indirectly through other sources which may have changed the data in some way. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. The Biological Resource Division shall not be held liable for improper or incorrect use of the data described and/or contained herein.

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