The scientists are now evaluating older animals. Gross, Woodward, Percival, and Ken Rice of the University of Florida began trapping adult females near their nests last summer. They aim to collect fat samples from the animals' abdomens and some of their eggs. Wildlife biologists know from studying many species that a mother animal may pass contaminants she has stored in her fat reserves on to her eggs. Gross, who will do the hormone and chemical evaluation, says the researchers hope to determine whether the mother alligators have accumulated significant amounts of chemicals that might be feminizing their offspring.
Preliminary research suggests they do.
Some birds on the lake have laid thin shelled eggs, says Fry. He begins a study this year to look for the sorts of reproductive abnormalities in Apopka birds that he has seen elsewhere. He recently discovered feminized sex organs in some male embryos of common terns collected near a toxic waste site in Massachusetts. To learn how fish eating anhinga and glossy ibis are faring, Fry is collecting eggs from Lake Apopka and other Florida lakes. He'll look for pollutants in the yolk sac and signs that the birds' livers are responding to them.