Organochlorine Contaminants in White-Faced Ibis Eggs in Southern Texas

Abstract

-White-faced Ibis (Plegadis chihi) eggs collected from two colonies in southern Texas in 1985 had low mean concentrations of DDE (0.14-0.27 ppm wet weight). DDD, the only other organochlorine contaminant detected, was found in only 1 of 20 eggs. DDE concentrations in eggs were not significantly correlated with eggshell thickness. Mean DDE concentrations were significantly higher in eggs collected from nests where not all of the remaining eggs hatched (1.0 ppm) than in eggs collected from nests where all the remaining eggs hatched (0.15 ppm). Received 20 April 1988, accepted 28 August 1988.