SEAWOLF REPORT, February 10, 2006

Are the Southern Resident Orca Whales Still in Danger?

It's been reported by researchers from the Center for Whale Research in the San Juan Islands, that the Southern Residents lost a few more of their members - L-107 (newborn), K31 (young male) and L-32 (older female) - but that last year also saw the arrival of five new babies, J-40, J-41, K-38, L-106 and L-107, which estimates the current population to be around 87 animals (which will certainly be changed once again when our three groups gather back in the Greater Puget Sound for a new count this spring).

So what has changed in the Sound? Toxic pollutants still ply the benthic organisms and sediments, yet Chinook fry numbers are increasing in some riparian runs; recreational and commercial boat traffic in increasing in the region, but the US Navy has reduced its practice of testing mid-frequency sonar by the DESRON 9 surface warfare group when whales are present; but are our whales 'cleaner' than they were in previous years?

No, they're not. Persistent Bioaccumulative Toxins (PBTs), such as Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) contaminate the tissue samples taken from resident whales, and these compounds, among others, accumulate and stay in the bodies of animals as they grow. PCBs in particular, are then passed from nursing mothers to their infants at a time when these pairs nurse - an important time that the young animals start to develop. In time, it's been determined that many of these whales are encountering increasing levels of reproductive or even developmental failures. And that's a situation that will certainly impact their development at some time down the road.

The biggest ecological concern is eventual sterility of breeding age animals. Experience accumulated in other localized whale populations, such as the St. Lawrence beluga, show that sterility is a daunting dilemma, and if the toxic accumulations in tissues of our local whales lead to reproductive failure, increased cancerous conditions, decreased immune response or bacterial infections, sterility might indeed be on the horizon. As we all know, after sterility, there is only disappearance.

That's why some local researchers still assert that this local population is 'on it's way out.' Estimates range from 30 to 50 years before the Puget Sound becomes absent of the cry of the orca.

The next four summers will be a benchmark period in the Sound. Researchers will continue to monitor the fluctuating orca population here in the region, and where the 'bargraph' lies in the next few years will signal the future population direction in which the Southern Resident pods are headed. In a closed, contained and regulated environment with no variables, 87 animals might just be a sustainable number of orcas, but we need to keep in mind that the impacts placed on this stock of whales is continuing, and that the threats and accumulation of stressors they face is hardly 'under control' or diminished... despite their new 'Endangered Species' status.

Our whales are clearly not out of danger; their future, still, remains uncertain. SeaWolf will continue to monitor and report on new issues facing these whales, as they arise.

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