Metal concentrations in osprey (Pandion haliaetus) populations in the Florida Bay estuary

Mercury and trace metal contamination is a concern in the Florida Bay estuary, but the effects on biological pathways are not very well understood. The analysis of mercury and trace metals (beryllium, vanadium, chromium, cobalt, nickel, copper, arsenic, cadmium, antimony, and lead) was conducted on tissues of adult and juvenile osprey (Pandion haliaetus) to examine the bioaccumulation and distribution in Florida Bay. Mercury concentrations were found at levels associated with decreased reproductive success, and no significant differences were found between adult and juvenile samples. Concentrations of other trace metals were generally below levels known to cause environmental problems. Mercury levels were particularly high in birds from central and eastern Florida Bay. In addition to mercury, vanadium was the only trace metal that showed significant geographic variation. Mercury concentrations in adult samples were comparable to levels reported in adult osprey from two other sites in North America, but concentrations in juvenile tissues were higher in Florida Bay. Although ospreys are a potential biomonitoring species for mercury contamination, further inter-population comparisons are needed, as well as additional information about the risks associated with bioaccumulation.