Tuesday, August 14, 2018

Orcas and Vessel Noise: Don’t Scapegoat Whale-Watch Boats

Everyone who lives in vicinity of the Salish Sea wants to save our endangered population of killer whales, and there have been a lot of ideas floated about how to do so. Donna Sandstrom’s recent Seattle Times op-ed (“Cut the toxins and boat noise, and boost salmon, so orcas can survive,” Aug. 18) suggested that, along with restoring the salmon runs that everyone needs, we need to do something about the whale-watch boats that often crowd around them in the summertime.

Her argument: The boats’ noise is causing these orcas to go hungry by interfering with their ability to echolocate their prey. It’s a solid argument, except for one fact: The whale watch boats are not the primary source of noise in the orcas’ waters.

From a visual viewpoint, it’s easy to lay the blame on the whale-watch boats. On some days you’ll see as many as forty or more of them jockeying for position in the waters of Haro Strait to get their customers the best possible view of the whales as they pass through.

Meanwhile, you’ll also see, off further in the distance, any number of large shipping vessels passing by, either heading in to Vancouver to unload their freight or heading out to see in the other directions. They usually are quite distant from the whales and don’t seem to pose a problem.

For the orcas, though, this is an illusion, since their universe is primarily an acoustic one. And in that universe, the large ships, not the small boats, pose the greatest challenge.

Listening by hydrophone, as I often do from my kayak in Haro Strait, opens a window into this universe. When the whale boats approach, their noise can be acute and high-pitched (though a number of the newer boats are impressively quiet), and the more of them, the worse it is. But the noise is also typically very short-lived and transient in nature.

The large shipping vessels, however, are another story. Both the noise created by water hitting their hulls and the sounds of their large engines can be nearly deafening under water. This is especially the case with older ships if the screws are old and bent or rusty. And worst of all, it is relentless: These auditory barrages can last continuously for 45 minutes or longer.

On more than one occasion, I’ve been listening to a pod of orcas communicating underwater when a large ship came into auditory view. The pod not only essentially fell silent and ceased communicating and echolocating, they essentially froze into position until the sound subsided enough that they could again see underwater with their echolocation sense. I’ve never seen this happen around the whale watch boats.

University of Washington marine scientist Scott Veirs has been studying this issue for years, assembling an impressive collection of data and transforming it into studies that make clear that large-ship noise in fact profoundly impacts killer whales.

“These ships are not only prevalent, but quite loud compared to other sources of noise in the ocean,” Veirs told one reporter. “Ships are dominating the soundscape.”

That doesn’t leave the whale-watch boats blameless, of course. One study found that the presence of whale watch boats increased the time that orcas spend altering their behavior due to noise, though only marginally – from 3.0 hours daily to 3.2.

It’s clear to most observers that there needs to be some kind of regulation of whale-watch boats in the San Juans, just to keep the crush from becoming too overwhelming. Certainly we should look at licensing them, with revocation of the license a potential punishment for bad behavior. And there need to be limits on how many boats can be around them at once. But banning them altogether will not help the orcas.

But if we’re concerned about vessel noise, then the first target has to be the gigantic freighters that are creating most of the racket out there and doing the most harm to orcas’ echolocation capabilities. Of course, it’s much easier politically and financially to go after small businesses like whale watch operations than large international shipping interests, but that doesn’t make it right.

Most of all, the entire issue is almost completely a diversion from the only real issue that matters for killer whales, and that issue is salmon. In times of salmon abundance, these issues fade to insignificance; but when there are few salmon, as there are now, they become increasingly magnified in importance.

Thanks to the tightness of all federal environmental budgets under the current administration, virtually every dollar spent on attempting to regulate them would be dollars NOT spent on recovering salmon habitat throughout their range.

Attacking scapegoats never solves the problem. In fact, it largely guarantees they will never be solved.