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Prevalence of eustrongylidosis in wading birds from colonies in California, Texas, and Rhode Island, USA

June 16, 2010

Snowy Egret (Egretta thula) and Black-crowned Night-Heron (Nycticorax nycticorax) nestlings from colonies in Texas, Rhode Island, and California and Great Egret (Casmerodius albus) nestlings from Texas were examined for eustrongylidosis, or infection by the parasitic nematode Eustrongylides spp. In 31% (24/77) of all broods examined, at least one nestling was infected. Snowy Egret broods from Texas were more frequently (100%) infected than those from California (20%) or Rhode Island (10%), and the prevalence of eustrongylidosis in 5- and 10-day-old Snowy Egret nestlings was higher in the Texas colony than the other two. Within the Texas colony, the frequency of eustrongylidosis was greater for Snowy Egret (100%) and Great Egret (80%) broods than for Black-crowned Night-Heron broods (12.5%). Also in Texas, eustrongylidosis was more frequent in 5-day-old Snowy Egret nestlings than 5-day-old Black-crowned Night-Heron or Great Egret nestlings, and in 10-day-old Snowy Egret nestlings than in 10-day-old Black-crowned Night-Heron nestlings. Eustrongylides spp. caused perforations of the gastrointestinal tract and peritonitis, particularly in Snowy Egrets.

Citation Information

Publication Year 1994
Title Prevalence of eustrongylidosis in wading birds from colonies in California, Texas, and Rhode Island, USA
DOI 10.2307/1521295
Authors J. C. Franson, T. W. Custer
Publication Type Article
Publication Subtype Journal Article
Series Title Colonial Waterbirds
Index ID 5222682
Record Source USGS Publications Warehouse
USGS Organization National Wildlife Health Center; Patuxent Wildlife Research Center; Upper Midwest Environmental Sciences Center