Abstract
Wetlands in the prairie pothole region of the U.S. can support large heronries which develop during prolonged flooding and wet-dry cycles. An estimated 5,949 breeding ardeid pairs comprised of 95% Cattle Egrets (Bubulcus ibis), 2% Black-crowned Night-Herons (Nycticorax nycticorax), 2% Great Egrets (Ardea alba), <1% Snowy Egrets (Egretta thula), and <1% Little Blue Herons (E. caerulea) nested in a heronry in the prairie pothole region of South Dakota in 1995. An abundance of aquatic foraging habitat during a wet hydrologic period was a major factor influencing heronry establishment. Nesting species were vertically stratified (X̄ nest height) with largest species nesting highest. The heronry developed from a core area that increased in nest density until saturated, followed by peripheral expansion. Vertical and horizontal nest position may have been a function of timing of nest initiation, nest density, and intraspecific competition.
Original language | English |
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Pages (from-to) | 199-206 |
Number of pages | 8 |
Journal | Waterbirds |
Volume | 19 |
Issue number | 2 |
DOIs | |
State | Published - 1996 |
Keywords
- Ardeidae
- Bubulcus ibis Cattle Egret
- Foraging habitat
- Nest stratification
- Prairie pothole region
- South Dakota
- Wetlands