Foraging Flights, Reproductive Success and Organochlorine Contaminants in Cattle Egrets Nesting in a Residential Area of Bryan, Texas‪.‬

Abstract. -- This study was designed to determine reproductive success, habitat use and foraging trips of Cattle Egrets (Bubulcus ibis) nesting in the small city of Bryan, Texas and to compare residues of persistent organochlorine compounds in eggs of Cattle Egrets from recent years with data collected in the past. Mean clutch size and reproductive success of egrets nesting in Bryan in 1993 and 1994 were not different from the state average reported for egrets in non-urban habitats. Cattle egrets flew non-randomly in and out of the colony predominantly alone or in pairs and foraged mostly in pastures with cattle at 10-15 km around the colony. The only organochlorine residues found at detectable levels were DDE and PCBs. Mean DDE levels in eggs were mostly at near background levels and were significantly lower than those reported for Cattle Egrets in the 1970s. **********