Feeding habitat characteristics of the Great Blue Heron and Great Egret nesting along the Upper Mississippi River, 1995-1998

Christine M. Custer; Susan A. Suarez; D.A. Olsen

doi:10.1675/1524-4695(2004)027[0454:fhcotg]2.0.co;2

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USGS · 1002960

Feeding habitat characteristics of the Great Blue Heron and Great Egret nesting along the Upper Mississippi River, 1995-1998

Christine M. Custer·Susan A. Suarez·D.A. Olsen

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Abstract

The Great Blue Heron ( Ardea herodias ) and Great Egret ( Ardea alba ) nested in eight colonies along the Upper Mississippi River, USA, and individual birds were followed by airplane to feeding sites during the nesting seasons in 1995-1998. Both species used braided channel/backwater habitats for feeding more than expected, based on availability, and open pool and main navigation channel less than expected. Most individuals of both species fed <5 km from their breeding colony and avoided sites >10 km away. Habitat and distance need to be considered simultaneously when assessing habitat quality for herons and egrets. The Great Blue Heron flew farther to feeding sites during the care-of-young period than during incubation and the Great Egret showed the opposite pattern. The Great Blue Heron tended to feed solitarily; only 10% of the feeding flights ended at a location where another heron was already present. About one-third of Great Egret feeding flights ended at a location with another egret already present. Colony placement on the landscape seemed to be a function of the feeding radius of each colony.

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Source-reported bounding extent: 40.48038142908172° to 44.63739123445585° latitude; -92.57080078125° to -89.93408203124999° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Christine M. Custer, Susan A. Suarez, D.A. Olsen. 2004. Feeding habitat characteristics of the Great Blue Heron and Great Egret nesting along the Upper Mississippi River, 1995-1998. https://doi.org/10.1675/1524-4695(2004)027%5B0454%3Afhcotg%5D2.0.co%3B2

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