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At least 523 records · Page 29Linked to original sources
USGS1980

Decline and disappearance of the Dusky Seaside Sparrow from Merritt Island, Florida

The Dusky Seaside Sparrow, Ammospiza maritima nigrescens , was first discovered by Charles J. Maynard near Salt Lake on the St. Johns River west of Titusville, Brevard County, Florida, on March 17, 1872. Later that spring, Maynard found the sparrow to be quite common in the salt marsh on the Canaveral Peninsula in what is now the Merritt Island National Wildlife Refuge on the John F. Kennedy Space Center. The first Dusky nests were found 42 years later when Oscar E. Baynard and Henry Simpson located three on the peninsula along the edge of Indian River on May 21, 1914. The sparrow was abundant in the marsh on the east of the Indian River until the 1950s. By the early 1960s, the sparrow had disappeared from much of its former range and a decline occurred in an area under study on Merritt Island.

American Birds↗
USGS1985

Atlantic Flyway review: Region V

Of in the 15 participating banding stations in Region Park V in the autumn of 1983, only Baltimore's Leakin Park was new. Two others that were active but not reported in 1982 rejoined us in 1983. Four of the 15 stations are home operations, 2 are on Federal land, 2 in city parks, 2 at private schools, 2 at coastal concentration spots, 1 on a wildlife sanctuary, 1 in an abandoned orchard, and 1 in an impending real estate development. Coverage and catch characteristics of each station are summarized in Table 1 and in the pie charts that accompany the station reports. The habitats sampled vary so much among stations that species and even family composition are unique at each site.

North American Bird Bander↗
USGS1990

Recent population trends of the eastern bluebird

North American Breeding Bird Survey data for the period 1966-1987 indicate that Eastern Bluebird (Sialia sialis) populations declined during the 1970s, primarily in association with either severe winters or severe spring storms. In recent years, bluebird populations have increased to levels similar to those observed during the first year (1966) of the survey. Survey results suggest that climate has an important role in affecting short-term population declines in bluebirds.

The Wilson Bulletin↗
USGS1994

Estimating equations estimates of trends

The North American Breeding Bird Survey monitors changes in bird populations through time using annual counts at fixed survey sites. The usual method of estimating trends has been to use the logarithm of the counts in a regression analysis. It is contended that this procedure is reasonably satisfactory for more abundant species, but produces biased estimates for less abundant species. An alternative estimation procedure based on estimating equations is presented.

Bird Populations↗