Mercury consumption increases homosexual tendencies in birds.
At least that’s what UF researchers discovered in a recent study led by wildlife ecology and conservation professor Peter Frederick.
Frederick directed the seven-year study on white ibises intending to confirm the hypothesis that increased mercury consumption would negatively effect the number of chicks the birds produced.
“We did not expect this,” Frederick said. “We expected changes in hormone levels and courtship behavior, which we found, but we did not expect that males would pair bond with other males.”
The team constructed a 13,000-square-foot facility, encasing 160 young ibises, which were divided into four groups made up of equal numbers of males and females. As the team confirmed their suspicions, they also discovered something new: As the amount of methylmercury in the birds’ systems increased, the proportion of males mating with males increased, too.
While previous studies have shown hormonal changes in birds due to methylmercury, this study is the first to find a change in sexual preference.
“We believe the change in sexual preference may be a result of changes both in hormones and development,” Frederick said. “However, this is purely speculative. We did not find nor can prove this as a mechanism.”
The study indicates the drastic changes mercury can make in wildlife populations, even in relatively low exposure rates. Frederick hopes it will persuade officials to pay attention to mercury regulation in the environment.
“Wildlife does not have a choice about what to eat as we do,” Frederick said.
