2011 State of the Birds

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Each year the State of the Birds report focuses attention on conservation issues that impact bird populations in the United States. 

In the 2011 report, bird distribution and land-ownership data provided the nation with an assessment of the status of birds on public lands and waters. These types of assessments are important not only because they demonstrate the importance public lands have  in conserving  birds; but also because they show stewardship opportunities available for the public land agencies managing these lands.

The State of the Birds Report 2011

Each year the State of the Birds report focuses attention on conservation issues that impact bird populations in the United States. 

(Public domain.)

State of the Birds partnership
The 2011 report was developed by the North American Bird Conservation Initiative in partnership with the Gap Analysis Project (GAP), the Cornell Lab of Ornithology, The Nature Conservancy, American Bird Conservancy, Association of Fish and Wildlife Agencies, Bureau of Land Management, the U.S. Geological Survey, Department of Defense/DOD Partners in Flight, Klamath Bird Observatory, National Audubon Society, National Oceanic and Atmospheric Administration, National Park Service, U.S. Fish and Wildlife Service, and USDA Forest Service.

Contributions by GAP

To determine the stewardship responsibilities and conservation opportunities for birds on public lands and waters, U.S. bird distribution information was overlaid onto a map of public land ownership (PAD-US) to determine the percentage of each species’ distribution on public land.  To represent the most accurate breeding and wintering distributions of birds in the contiguous 48 states, bird observation data from eBird (www.ebird.org) were analyzed.  For Alaska bird distributions, vegetation layers were used to modify bird range data from the Alaska Gap Analysis Project and NatureServe. State of Hawaii biologists compiled and analyzed distributions for Hawaiian bird species. Bird distributions for Puerto Rico, U.S. Virgin Islands, Guam, Commonwealth of the Northern Mariana Islands, and American Samoa were based on distribution of suitable habitat identified by local experts. For most ocean species, the best available colony-nesting data were used to evaluate the breeding distribution. 

GAP’s Protected Areas Database of the United States (PAD-US version 1.1) was used to determine land ownership and biodiversity protection status of all public lands for the continental U.S., Alaska, Hawaii, Puerto Rico, and the U.S. Virgin Islands.

GAP’s National Land Cover data were used to estimate the extent of each primary habitat within public lands.   The 590 ecological systems and land-use classes were categorized into primary habitat designations for the analysis. These data were then overlaid with PAD-US to calculate the area of each primary habitat on public lands (not including coasts, islands, and oceans).

To calculate the percentage of each species’ distribution within public land ownership and biodiversity protection categories for the continental U.S., the bird distribution model or frequency map for each bird species was projected onto PAD-US. By combining these datasets, analysts calculated the percentages of species distributions on public lands and identified public agencies responsible for managing lands where each species occurred.

Visit the State of the Birds website.