Iowa marsh birds, density-area relationship
Species richness and density of Iowa marsh birds were positively correlated with marsh area, but area accounted for 69% of the variation in species richness and only 19% of the variation in density. Although densities of five of nine species examined correlated with marsh area, total density was not significantly correlated with area when the effects of species richness were eliminated. Area was the most frequent significant variable in regression equations for species richness, total density, and the densities of nine individual species on six variables. Unlike species-area relationships, density-area relationships are relatively weak, and knowledge of other ecological factors would provide more useful information for the design of nature preserves. The increases in total density and densities of four individual species with area provide only limited support for the MacArthur-Wilson island biogeography hypothesis, but data on reproductive success will be needed to provide an unequivocal test.
Journal of the Iowa Academy of Science
© Copyright 1991 by the Iowa Academy of Science, Inc.
Brown, Mike and Dinsmore, James J.
"Area-dependent Changes in Bird Densities in Iowa Marshes,"
The Journal of the Iowa Academy of Science: JIAS: Vol. 98:
, Article 5.
Available at: http://scholarworks.uni.edu/jias/vol98/iss3/5