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Abstract
Mercury is a toxic, pervasive environmental contaminant that can be transferred from mother to offspring during development. We examined how maternally-transferred mercury and incubation temperature influence reproductive success, offspring behavior, and subsequent survival in American alligators. We collected alligator eggs from a mercury contaminated reservoir on the Savannah River Site, SC, and incubated them at female- and male-promoting temperatures. Mercury in egg yolk ranged from 0.248–0.554 ppm compared to 0.018–0.052 ppm for a low mercury site; levels in hatchling blood ranged from 0.090–0.490 ppm. We found mostly negligible correlations between life history traits and mercury but noted a positive relationship with egg mass. Incubation temperature exerted strong effects on hatchling phenotypes, with male-promoting temperatures producing larger, bolder hatchlings with increased survival. Overall survivorship over eight months was ~20%. Our study suggests that incubation temperature has a stronger effect on alligator neonate behavior and survival than maternally-transferred mercury.