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Waterbird Conservation Glossary

Annual Population Indices for North America: The Christmas Bird Count (CBC) Annual Index Graphs show the annual population indices of each species using CBC data from 1965-66 through 2003-04. The annual indices are determined by taking into account the number of birds seen in each circle, the detectability of the species, and the amount of effort that was spent looking for birds in each circle. The values can be thought of as the number of birds that could be expected to be seen on a CBC each year, assuming an average amount of effort in each circle, averaged across all CBC circles where the species occurs. These population indices are copyright National Audubon Society, Inc. 2006, all rights reserved.

Bird Conservation Region (BCR): BCRs are ecologically distinct regions in North America with similar bird communities, habitats, and resource management issues. BCRs may be partitioned into smaller ecological units when finer scale conservation planning, implementation, and evaluation are necessary. Conversely, BCRs may be aggregated to facilitate conservation partnerships throughout the annual range of a group of species, recognizing that migratory species may use multiple BCRs throughout their annual life cycle. BCRs also facilitate domestic and international cooperation in bird conservation because these areas of relatively homogenous habitats and bird communities traverse state, provincial, and national borders (U.S. North American Bird Conservation Initiative Committee, Bird Conservation Regions, 2006).

Christmas Bird Count (CBC): Audubon’s annual census of early-winter bird populations. All CBC locations are circles 15 miles in diameter, and birds are counted during one calendar day per circle between the dates of 14 December and 5 January. More than 50,000 observers currently participate at over 2000 locations throughout the Americas each year, in the longest running bird monitoring program in ornithology. For over a century, volunteers have been collecting information on the birds in their communities, and the results of their efforts have been compiled into the CBC database – more than 100 years of unbroken data on bird population trends across North America. The CBC is citizen science in action, and provides opportunities to meet other local volunteers, hone birding skills, and take part in a meaningful and rewarding seasonal tradition.

Endangered Species: An animal or plant species in danger of extinction throughout all or a significant portion of its range. This federal status engenders intensive protective measures (U.S. Fish and Wildlife Service 2006).

North American Breeding Bird Survey (BBS): The BBS is a cooperative effort between the U.S. Geological Survey's Patuxent Wildlife Research Center and the Canadian Wildlife Service's National Wildlife Research Centre to monitor the status and trends of North American bird populations. Following a rigorous protocol, BBS data are collected by thousands of dedicated participants along thousands of randomly established roadside routes throughout the continent. Professional BBS coordinators and data managers work closely with researchers and statisticians to compile and deliver these population data and population trend analyses on more than 400 bird species, for use by conservation managers, scientists, and the general public.

Threatened Species: An animal or plant species likely to become endangered within the foreseeable future throughout all or a significant portion of its range (U.S. Fish and Wildlife Service 2006).

WatchList: Audubon’s science-based early warning system for bird conservation. Audubon’s WatchList identifies at-risk bird species of international and national conservation concern. WatchList species are those facing population declines and/or threats such as loss of breeding, wintering, or migratory habitat, or those with limited geographic ranges. A centerpiece of conservation at Audubon, the WatchList focuses attention on at-risk bird species so that limited resources are spent where they are most needed.

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