Metals in Laysan albatrosses from Midway Atoll

We examined the concentrations of lead, cadmium, selenium, chromium, manganese, arsenic, tin, and mercury in the heart, liver, kidney, salt gland, and feathers of adult (n = 10) and young (n = 15) Laysan albatrosses (Diomedea immutabilis) from Midway Atoll in the north-central Pacific Ocean. Lead poisoning has been reported in some Laysans nesting near buildings on Midway, but other heavy metals have not been examined. We examined tissue distribution of metals by age and gender (adults only). We also examined tissue concentrations in three birds with a droop-wing syndrome characteristic of lead poisoning. We compared metal levels in salt gland (a special excretory organ of marine birds) with those in other tissues. All metals varied significantly across tissues in both adults and chicks, and the relative tissue concentrations were similar in adults and chicks for most metals. Adults had higher levels of most metals in most organs, with significant differences mainly for cadmium (up to 20 x higher in kidney and salt gland) and for mercury (17 x higher in kidney). However, chicks had significantly higher manganese in liver and arsenic in salt gland. The salt gland had concentrations of most metals (except cadmium, selenium, and mercury) comparable to the kidney levels, which is consistent with it serving as an excretory organ for the cations. Chicks with droop-wings had very elevated levels of lead in their tissue (16.8 ppm in feathers, 14 ppm in liver and kidney), whereas levels of other metals were not significantly different from the apparently normal chicks.