When marine fish stocks decline, pinnipeds (seals and sea lions) often take the blame. Seal hunters in Canada after (wrongly) accuse seals of eating all the cod and in the Pacific northwest of the United States it appears that sea lions are being blamed for depleting salmon stocks. I first heard about this issue in a book I randomly picked up in the Baltimore, MD Barnes & Noble a few years ago, and what scientists found was that the sea lions were not eating any significant amount of salmon, at least until a “fish ladder” was created to help the fish get upstream and they became easy prey.
Years later, the debate is still raging and now a sea lion in the Columbia river has been shot twice for stealing a fish off someone’s line (it appears from the article that the fisherman didn’t do the shooting, but it was another person in the area). It seems like the sea lion is alive for the moment, but this could very soon change as the bullets could cause deadly infection. What has yet to be proven, just like the passage in the book (I wish I could remember it’s name), is that the sea lions are actually a major factor in the declining salmon fishery, and I suspect that they are once again being used as a scapegoat for poor management and biological degradation. In all this talk not once have I seen the findings of an outside scientist (i.e. not affiliated with the government or National Marine Fisheries Service) as to what these animals are eating, and if it’s salmon, how much of their diet is composed of salmon. How can we make management choices, especially ones advocating lethal force on a species previously protected under the Marine Mammal Protection Act, without any serious study of what’s happening?
Others have noticed this issue as well.
“It won’t save declining salmon runs in the Columbia River, because the sea lions aren’t the problem.” said Sharon Young, national marine issues field director for [the Humane Society of the United States]. “It seems that it is easier to scapegoat the sea lions than to try to address these other more politically charged and complex issues.”
Recently, Japanese whalers have blamed Humpback Whales for declining fish stocks, but of course we already know their motives behind this statement; Humpbacks are next on the list to be hunted, which will likely cause greater outcry being they are one of the most powerful symbols of the ocean. Luckily, however, the case for further whaling is looking worse and worse and I hope it is entirely shut down soon.
In any event, I don’t believe marine mammals are having big impacts on fisheries like some claim, and in fact they actually help fisheries by eating competing fish and other predatory fish (especially in the case of seals and sea lions) so eliminating them would be a HUGE mistake. While I hope the issues in Oregon are resolved soon, somehow I get the feeling that as long as we have declining fish stocks, marine mammals are going to get the blame instead of mismanagement by humans.