Steller sea lions as sentinels of environmental contaminants in the Aleutian Islands

November 1, 2013 • Filed under: News — Peter.Prokein

Steller sea lions are a relatively long-lived species (30-40 years) that are predominantly predators on marine fish so they can both bioaccumulate and biomagnify environmental toxicants that are present in their food web in coastal Alaska.

Friday Seminar Series

  • What: Steller sea lions as sentinels of environmental contaminants in the Aleutian Islands
  • Who: Lorrie Rea
  • When: 3:30-4:30 p.m., Friday, Nov. 1
  • Where: Duckering 531

Recent findings of relatively high total mercury concentrations in the hair of young sea lion pups in the western Aleutians Islands has raised concern over the direct impact of this and other toxicants to the health of this endangered species, particularly at a sensitive stage of development. Since Steller sea lions are distributed throughout the southern coastal waters of Alaska and Russia, sampling of total mercury concentrations in hair samples collected from Steller sea lion pups throughout their Alaska distribution range and into Russia provides map of total mercury levels in the respective food webs across this section of the North Pacific coastline. We also utilized levels of nitrogen and carbon stable isotopes in fetal whisker sections to illustrate that adult female Steller sea lions which delivered the highest concentration of total mercury to their pups in utero, were likely eating higher trophic level prey. This research illustrates how valuable high trophic position marine predators can serve as sentinels of environmental health in remote regions of Alaska.