Heavy metal and organochlorine pollutants in Antarctic vertebrates
As top predators seabirds have the potential to accumulate marine pollutants. This study quantified heavy metal loads in 3 species of albatross.
From the abstract of the referenced paper:
Cadmium and mercury concentrations were measured in the tissues of 64 individual albatrosses (23 wandering albatrosses - (Diomedea exulans), 9 royal albatrosses (Diomedea epomophora) and 32 shy albatrosses (Thalassarche cauta)) which were killed as by-catch in longline fishing activities between 1991 and 1994. Mercury concentrations were also determined for 33 shy albatross eggs (excluding shells). The birds were all sexed and assigned to one of two age classes (immature and adult). The three species exhibited differences both in overall concentrations of cadmium and mercury, and also in the pattern of accumulation of metals with age and sex. Wandering albatrosses exhibited the highest mercury concentrations with a mean concentration in adult liver samples of 920.0 plus or minus 794.1 micrograms per gram dry weight. Shy albatrosses had the lowest mercury concentrations with mean concentrations in adult livers of 36.3 plus or minus 21.4 micrograms per gram dry weight. The highest mercury concentration was 1800 micrograms per gram for an adult female wandering albatross. Cadmium concentrations were less variable, with adult royal albatrosses having the highest average concentrations (180.0 plus or minus 165.0 in adult kidneys) and adult shy albatrosses the lowest (40.1 plus or minus 20.0 in adult kidney). The highest individual cadmium concentration was 287 micrograms per gram for a juvenile wandering albatross. There was no evidence of increased accumulation of cadmium with age in any of the species, but wandering albatrosses showed higher mercury concentrations in adults than juveniles. Female wandering albatrosses also had significantly higher mercury concentrations than males. The mercury contents of the shy albatross eggs were very low, with a maximum concentration of 5.4 micrograms per gram. The results of this study are consistent with the findings of previous work on albatrosses and support the notion that the life-history strategy of these species (i.e. long-lived with low reproductive output) may be an important determinant in the concentrations of some metals found in their tissues.
It should be noted that there is a significant typographical error in the abstract of the published paper, where shy albatross mercury concentrations are expressed in milligrams instead of micrograms.