Boat noise is contributing to the starvation of our orcas
March 10, 2009 · Updated 3:54 PM
Experts agree our local orca population is starving.
I support Mark Anderson’s recent guest column (Feb. 11) where he writes that the proximal cause of death last year of seven local orcas was starvation, and whale watching is accelerating their starvation.
The whale-watching industry is comprised of fast powerboats which are highly efficient in locating orcas. Because of their known success rates, they attract private craft in the area. The consequence: our local whales are followed around the clock by swarms of vessels and get little rest from power engines. Noise harassment is not the intention, but it is certainly a result.
The National Marine Fisheries Service has identified what is obvious: that human-generated sound has the potential to mask echolocation and other signals used by orcas to detect and capture prey. Thus, even with well-meaning distance guidelines and on-water stewardship programs (requiring more boats) to educate vessel operators engaged in whale watching, the simple presence of the volume of boats that collect and follow the whales interferes with their ability to hunt, forage, communicate and capture prey. The reduced ability to capture prey equals starvation.
I doubt commercial whale watching is the No. 1 contributor to the recent deaths of eight orcas, a number which includes the most recent orca, L57, who is missing and presumed dead.
You could argue that the population crash of their primary food source, chinook salmon, and the tremendous build-up of pollution in their environment are the two most lethal contributors to their demise. However, fixing these two problems could take many years. Halting the current excessive level of vessel noise is the only factor we can immediately control.
These are very trying times economically, and there is no doubt that humans use orcas as a revenue source. I can sympathize, but orcas do not have a vote in this controversy.
It seems clear that without strict regulations limiting or halting commercial whale watching, something is going to give in a very dramatic and unfortunate way for our Southern resident orcas.
San Juan Island