Harbor seals are unfortunate and unwitting barometers for our polluted environment. An ecosystem poisoned by mankind with contaminants, sewage, trash and inorganic marine debris directly impacts their health and that of all living beings in and around the waters of Puget Sound, Elliott Bay and the Duwamish River.

Harbor seals in particular are affected by pollution because they do not migrate, but instead, live year-round in our region. Their thick layers of blubber absorb and retain pollutants from our industrial waterways. In fact, a 2005 study showed the harbor seals of South Puget Sound were 7 times more contaminated than those living in Canada’s Georgia Strait. Biologists use tissue samples from both live and dead seals to monitor the health of the Sound, measuring levels of PCBs, increasing numbers of chemicals used in flame retardants known as
PBDEs, pesticides and other highly toxic waste.

While a ban of PCBs has reduced those toxins in recent years, the number of chemicals used in flame retardants (including those known as PBDEs) have greatly increased. Studies show that PBDE concentrations have been doubling every 3.5 years and have even been detected in the high Arctic. Contaminants are stored in the blubber of marine mammals at the top of the food chain, such as dolphins, seals and orcas. The Southern Resident orcas are among the most contaminated marine mammals in the world. These toxins pass from generation to generation through the milk of mothers to their offspring. Humans, of course, are also at the top of the food chain - and those who consume fish from these toxic waters have high contaminant loads.

Harbor seal pups from our area, the Main Basin of Puget Sound, are more highly contaminated with PCBs and PBDEs than other areas of Puget Sound. Sadly, because seal pups are so contaminated, they are considered the ideal subject for these studies. Read the full study of contaminants in Puget Sound here.

Exposure to flame retardants causes physical abnormalities (including that of the brain, impairing the development of motor activities and cognition), behavioral changes, impairs reproduction and causes immune disorders.

Recently biologists have discovered a link between contaminants and compromised immune systems of harbor seals. Weakened seals become vulnerable to parasitic infections, low body weight and numerous viruses, often leading to fatalities. Harbor seals and pups forage for food and haul out on the wooden piers and beaches in the highly industrial and contaminated Duwamish Waterway, a superfund project. A number of pups in this location were found by PAWS and WA Fish and Wildlife to have lungworm infestation, pneumonia and/or a fatal virus.

Storm runoff adds (among other pollutants) human and animal waste, agricultural chemicals, highway oil and gasoline residue. Additionally, household chemicals and pharmaceuticals flushed down a drain end up in our waters --- and ultimately into our fish, seals and other marine mammals. Puget Sound now has areas where no marine life can subsist, known as "dead zones". View the recent Frontline PBS documentary "Poisoned Waters" which features our troubled Puget Sound here.

Marine debris and trash is dangerous to seals, sea lions and other sea life. Plastic bags and balloons are often mistaken for food. If consumed by marine mammals, it can result in a slow and painful death. Plastic litter does not biodegrade; instead, it “photo-degrades” --- a process where sunlight breaks it down into minute pieces of plastic that enter the food chain. These plastic polymers are a magnet for pcbs and other toxic chemicals. Once ingested they create hormonal imbalances and affect reproductive abilities and brain activity in fish, invertebrates and marine mammals. Plastic litter from all over the earth ends up in the ocean, gets caught up in ocean currents and has created a giant swirling mass of 7 million tons of
toxic debris twice the size of Texas --- dubbed the "Great Pacific Garbage Patch." The waters in this immense area contain 6 times more plastic than plankton, a primary food source for fish and marine mammals. The contaminant-laced plastic is found at all levels of the food chain in our oceans, ultimately affecting humans as well who consume seafood. To find out more about this environmental health disaster and to view a video, please click here and explore the links listed below.

Each year, many thousands of marine mammals and sea birds get entangled in marine debris, including fishing line and tackle (such as the endangered Steller sea lion in the photo at left who has swallowed a hook with "flasher"), derelict gear, nets, plastic and metal box straps - resulting in horrific injury or death. Please do your part to help by removing any trash or fishing debris from the beach or water.

In 2011, Seal Sitters rescued an emaciated seal pup, nicknamed Sandy, from a West Seattle beach. Sandy was successfully rehabilitated at PAWS Wildlife Center, fitted with a satellite tracking device and released back to the wild early in 2012. She travelled throughout the waters of Puget Sound for the next few months, but tragically was found dead, entangled in derelict fishing line. Read about Sandy


Seattle Times, Puget Sound harbor seals help scientist track pollutants
U.S. Environmental Protection Agency, Puget Sound Georgia Basin Ecosystem indicator report
Burning Issue: Flame retardants in harbor seals
U.S. Environmental Protection Agency: Puget Sound Georgia Basin Toxics in Harbor Seals

Seattle Times (May 2009) Beyond Puget Sound: Ten ideas for saving the Salish Sea
Seattle Times (June 2008), Failing our Sound
Seattle Post-Intelligencer (P-I), The Sound of broken promises
Seattle P-I, A rising tide of chemicals and pollutants
Seattle P-I, Our troubled Sound
Seattle P-I, Orcas so full of pollutants, it’s enough to sicken them
Seattle Times, Stormwater’s damage to Puget Sound huge, report says
USA Today, Puget Sound in declining health
Troubled Waters: Hood Canal’s dead zone
Seattle Times, Scientists tally damage a day after fish die-off in troubled Hood Canal

Pacific Ocean "Dead Zone" in Northwest may be irreversible (October 9, 2009, LA Times)
An oxygen-depleted "dead zone" the size of New Jersey is starving sea life off the coast of Oregon and Washington and might be impossible to reverse.

Duwamish River Cleanup Coalition. An alliance of community, environmental and small business groups whose mission is to clean up the Duwamish River.

Puget Soundkeeper Alliance. A team of dedicated staff and volunteers whose mission is to stop pollution from entering Puget Sound.

People for Puget Sound. Established to protect and restore the health of Puget Sound land and waters through education and action.

Beached whales killed by ingesting plastic, (Dec 18, 2009) Seven sperm whales that beached in Italy died from ingesting plastic in the ocean.
The Great Pacific Garbage Patch, Wikipedia. A definitive resource for information with many links.
The Great Pacific Garbage Patch, Good Morning America. video.
The World's Largest Dump: The Great Pacific Garbage Patch. Discover Magazine.
Capt. Charles Moore on the seas of plastic ~ Video on TED.com. Compelling video of Charles Moore, founder of the Algalita Marine Research Foundation. He captains the foundation's research vessel, the Alguita, documenting the great expanses of plastic waste that now litter the Pacific.
Algalita Marine Research Foundation. Algalita's current research includes the prevalence and quantification of plastic debris in the North Pacific Sub-tropical Gyre (NPSG), biological impact of plastics on marine life and the human food chain, and the desorption of plastic toxins into the ambient ocean water. This site includes much valuable in-depth technical information on the Great Pacific Garbage Patch which is contained within the North Pacific Gyre ("gyre" is a swirling vortex of currents).
How Stuff Works: The Great Pacific Garbage Patch.
Plague of Plastic Chokes the Seas, Los Angeles Times.


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photos copyright © 2007-2012
Robin Lindsey all rights reserved