Northern Prairie Wildlife Research Center
Abstract: We compared breeding bird populations in North Dakota using surveys conducted in 1967 and 1992-93. In decreasing order, the five most frequently occurring species were Horned Lark (Eremophia alpestris), Brown-headed Cowbird (Molothrus ater), Western Meadowlark (Sturnella neglecta), Red-winged Blackbird (Agelaius phoeniceus), and Eastern Kingbird (Tyrannus tyrannus). The five most abundant species - Horned Lark, Chestnut-collared Longspur (Calcarius ornatus), Red-winged Blackbird, Western Meadowlark, and Brown-headed Cowbird - accounted for 31-41% of the estimated statewide breeding bird population in the three years. Although species composition remained relatively similar among years, between-year patterns in abundance and frequency varied considerably among species. Data from this survey and the North American Breeding Bird Survey indicated that species exhibiting significant declines were primarily grassland- and wetland-breeding birds, whereas species exhibiting significant increases primarily were those associated with human structures and woody vegetation. Population declines and increases for species with similar habitat associations paralleled breeding habitat changes, providing evidence that factors on the breeding grounds are having a detectable effect on breeding birds in the northern Great Plains.
This resource is based on the following source (Northern Prairie Publication 0983):
Igl, Lawrence D., and Douglas H. Johnson. 1997. Changes in breeding bird populations in North Dakota: 1967 to 1992-93. The Auk 114(1):74-92.
This resource should be cited as:
Igl, Lawrence D., and Douglas H. Johnson. 1997. Changes in breeding bird populations in North Dakota: 1967 to 1992-93. The Auk 114(1):74-92. Northern Prairie Wildlife Research Center Online. http://www.npwrc.usgs.gov/resource/birds/birdpop/index.htm (Version 31JUL97).
Installation: Extract all files and open index.htm in a web browser.birdpop.zip ( 96K) -- Changes in Breeding Bird Populations in North Dakota: 1967 to 1992-93