Year: 1981
Type: article
Abstract: we examined changes in avian species richness and densities over each season for four and one- half years.Data are from a variety of riparian areas along the lower Colorado River.We found that species richness and density estimates tended to vary through time and space in a nonrandom fashion, resulting in skewed or abnormally peaked distributions.Investigating this further with an analysis of variance, we found that significant variation is introduced through differences in the kinds of dominant vegetation present, vertical structure being nearly the same, and by seasonal variation.Both of these factors were further affected by annual changes; that is, the extent of variation in species richness and densities differed, not only from one type of vegetation to another and from season to season, but also from year to year.We concluded that one must be cautious in making inferences from comparative data collected in: (1) the same year but in different seasons;(2) vegetation differing in plant species composition even though structurally similar; and (3) the same season and vegetation but in different years.Before meaningful habitat evaluations can be made, data should be collected over several seasons and years.
Authors: Anderson, Bertin W., Ohmart, Robert D., Rice, Jake
Language: English
Topic: Avian ecology and behavior
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDG: Life on land
Open Access status: green
OpenAlex ID: W7005876373