Biomarkers of contaminant exposure in common terns and black‐crowned night herons in the Great Lakes

Abstract

AbstractMorphological and biochemical indexes of contaminant exposure were examined in hatching common terns (Sterna hirundo) and black‐crowned night herons (Nycticorax nycticorax) from industrialized and nonindustrialized locations in the Great Lakes. In 1984, naturally incubated, pipping common tern and black‐crowned night heron embryos collected from industrialized locations exhibited smaller femur‐length‐to‐body‐weight ratios, elevated hepatic microsomal aryl hydrocarbon hydroxylase (AHH) activities, and lower hepatic DNA concentrations (P < 0.05). In addition, a high incidence of subcutaneous edema was noted in pipping herons (P < 0.01). In 1985, reduced hatching success was observed for laboratory‐incubated common tern eggs collected from the industrialized sites, compared to nonindustrialized sites (P < 0.01). Day‐old hatchlings exhibited reduced femur‐length‐to‐body‐weight ratio, developmental anomalies, and elevated hepatic AHH activity (P < 0.05). For hatching common terns studied in 1984 and 1985, femur‐length‐to‐body‐weight ratio was inversely related to AHH activity (r = −0.67, P < 0.05) and inversely related to log‐transformed PCB concentrations (r = −0.70, P ≤ 0.05) of unincubated eggs from the same colony. The activity of AHH in hatching terns was also directly related (r = 0.71, P ≤ 0.05) to log‐transformed PCB concentrations in unincubated eggs. Other examined contaminants, including DDE, other organochlorine pesticides, and mercury, were not directly related to these effects.