Metals in Eggs of the California Least Tern in Southern California

Abstract

Eggs of the endangered California Least Tern (Sterna antillarum browni) which nests in coastal southern California were analyzed for 10 heavy metals. Mean values ranged from 12,241 ng/gm (ppb) for zinc to 70 (ppb) in cadmium; concentrations of barium, mercury, and tin were below detection limits. Levels of selenium (761 ppb) and lead (1 10 ppb) tentatively recorded were thought to warrant further more detailed study as they may be approaching levels which could impair reproductive success in this species.