Supporting Research
In partnership with U.S., Canadian, and Norwegian collaborators, Orca Conservancy Research Associate Chloe Kotik is working to unlock the secrets of killer whale contamination.
The Contaminant Crisis
After decades of industrial, commercial, and consumer use, polluting chemicals like polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) have spread throughout the world’s oceans. These chemicals, collectively known as persistent organic pollutants or POPs, are slow to break down in the environment and difficult for organisms to metabolize or excrete. As a result, they tend to accumulate in animal tissues in a process known as bioaccumulation. When predators consume prey, they also absorb the pollution that has accumulated in their prey’s bodies, leading to the biomagnification of pollutants in the tissues of top predators. These contaminants can also transfer from mothers to offspring during pregnancy and nursing.
T124A4 Sabio, T124A1A Sabine, and T124A4A Strix, taken by Tamara Kelley
Some POPs have been linked to negative health outcomes in other marine mammals, including the disruption of hormones, important cell signalers that regulate growth, reproduction, and the everyday maintenance of being alive. However, the effects of POPs on killer whale health and hormone activity are not well-understood. To get to the bottom of the mystery, Orca Conservancy Associate Researcher and University of Alaska Fairbanks graduate student Chloe Kotik is partnering with researchers from Fisheries and Oceans Canada, Bay Cetology, Simon Fraser University, the University of Oslo, the Norwegian Institute of Life Sciences, and Raincoast Conservation Foundation to analyze concentrations of POPs and hormones in the tissues of West Coast Transient killer whales.
Chloe Kotik analyzing biopsy samples / Sample from T63 “Chainsaw”
What We Can Learn
When it comes to investigating killer whale health, West Coast Transient killer whales are the ideal study population: well-known and increasing in abundance, but still facing many of the same threats that endanger Southern Resident killer whales in their shared habitat. The results of this study will help us to better understand how Southern Resident killer whales are impacted by toxic contaminants.
J27 Blackberry in front of downtown Seattle, taken by Tamara Kelley