Breeding Bird Survey

A breeding bird survey monitors the status and trends of bird populations. Data from the survey are an important source for the range maps found in field guides. The North American Breeding Bird Survey is a joint project of the United States Geological Survey (USGS) and the Canadian Wildlife Service. The UK Breeding Bird Survey is administered by the British Trust for Ornithology, the Joint Nature Conservation Committee, and the Royal Society for the Protection of Birds.

The results of the BBS are valuable in evaluating the increasing and decreasing range of bird population which can be a key point to bird conservation. The BBS was designed to provide a continent-wide perspective of population change.

The North American Breeding Bird Survey was launched in 1966 after the concept of a continental monitoring program for all breeding birds had been developed by Chandler Robbins and his associates from the Migratory Bird Population Station. The program was developed in Laurel, Maryland. In the first year of its existence there were nearly 600 surveys conducted in the east part of the Mississippi River. One year later, in 1967, the survey spread to the Great Plains states and by 1968 almost 2000 routes had been established across southern Canada and 48 American states. As more birders were finding out about this program, the activity of BBS kept on increasing. In the 1980s, Breeding Bird Survey included areas such as Yukon, Northwest Territories of Canada and Alaska. Moreover, the number of routes placed in a number of states has had increased. Nowadays, BBS counts approximately 3700 active routes in the United States and Canada. From all the BBS routes, approximately 2900 are surveyed on a regular basis, each year. The density of the routes varies greatly across the continent and the largest number of routes can be found in New England and Mid-Atlantic states, in which there are more skilled birders to study the behavior of birds. Many bird watchers participate in these surveys as they find the experience rewarding. Currently, the BBS is planned to be expanded to parts of central and western North America as well as northern Mexico.

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