Tracing pathways of mercury exposure to Alaska pinnipeds in the Aleutian Islands and the Bering Sea

Project Info

Lead Researchers

  • Lorrie Rea (PI)
  • Todd O’Hara (co-PI)
  • Matthew Wooller (co-PI)
  • Brian Taras (co-PI)

Project Team

Scientists/Research Professionals

  • Julie Avery
  • J. Margaret Castellinii
  • Stephanie Crawford
  • Angie Gastaldi

Students

  • Nicole DelPino (Veterinary Scholar)
  • Sarah Chinn (Visiting Scientist) 
  • Tim Bouta (Undergraduate Scholar)

Project Dates

1 July , 2016 – 30 June, 2019 (3 years)

Project Location

Project Summary

The goals of this research are:

1

To describe and better understand regional, ecological and species-specific patterns of THg, methylmercury (MeHg) and TSe concentration (and their interactions) in several Alaskan pinnipeds, in the context of their chemical feeding ecology (trophic position assessed through bulk stable nitrogen isotope analysis) and foraging ecology.

Who: Do seals, sea lions and fur seals in the same region have the same amount of mercury in their body?

What: Does what they eat impact the amount of mercury in pinnipeds?

Where: Does where they eat (coastal vs. deep ocean) impact the amount of mercury in pinnipeds?

Why: Does the who, what and where effect the amount of protective selenium pinnipeds consume?

2

To assess potential differences in baseline stable nitrogen isotope (δ15N) values in SSL food webs and the trophic position of late gestation SSL females using compound-specific δ15N analysis of amino acids extracted from adult female vibrissae (whiskers).

We know that what Steller sea lions eat during the year gives them a seasonal pattern in stable nitrogen isotope (δ15N) values. What we don’t know is are these changes due to the type or location of fish they are eating (food web position) or what the fish themselves are eating (environment baseline)?