Kelpscape

Speed Kills Whales

Along with other passengers aboard the Islander, I watched a threesome of humpback whales in the Santa Barbara channel on Sunday, north of Anacapa and near the shipping lanes.

As the LA Times reports, several environmental groups including the Environmental Defense Center have filed a petition requesting a mandatory 10-knot speed limit within California's national marine sanctuaries, including the Channel Islands sanctuary. Presently, when whales are in the channel, ships are advised of the fact to slow down; but few do.

Ship strikes routinely kill whales, both inside and outside the sanctuaries. Blue, humpback and gray whales visit the sanctuary in significant numbers; many others  occasionally.  The whales may not hear the ships coming; ships have become quieter since the advent of hull shapes that minimize the wake (which, after all, takes energy to produce and so robs power from the ship's engines). Whales have terrific hearing but the channel is a very noisy environment.

The whales tend to congregate near the 200-meter depth contour, as records of whale sightings from the Cascadia Research Collective and Channel Islands Naturalist Corps suggest. There's some suggestion that they feed there; on the other hand, a lot of them seem to be engaged otherwise; the captain suggested that the 3 we saw were mating, for example.

The ships tend to stay pretty well within the shipping lanes (these are on either side of the pink stripe in the maps). That cuts across the 200-meter line at the East end of the channel, where we saw the trio of humpbacks on Sunday. That's definitely the most crowded part, with boats making the hop from Ventura or Oxnard to the islands at their closest approach to the mainland, as well as ships and whales. In principle, ships could travel through the channel more slowly, or take the longer path around the islands.  That would add time to the passage from the Far East, making factories in the Far East less competitive with US manufacturing. That doesn't seem particularly undesirable. 

The people who control the speed of the ships are their owners, most of them in other nations; ships are expensive and the owners are keen to have their investment pay off.  From their standpoint, from a purely economic perspective, faster ships and shorter routes between the same ports pay off faster.

 It would seem to me, the blogger, that big ships should avoid areas crowded with whales and boaters; or at least drive carefully and pay a premium as well.  The cost of futons may increase a little bit; but I'd be glad to pay a little more to give the whales plenty of space for their fun.

 

Krill

Krill have been plentiful in the channel lately.  This was a particularly dense, but small, clump of kirll I came across at Tajiguas. The dense krill is drawing lots of blue and humpback whales. The large numbers of whales congregating near shipping lanes  motivated the Coast Guard to issue a warning to ships transiting the channel; but ships have not been slowing down. The Environmental Defense Center has initiated a lawsuit demanding that the Coast Guard make speed limits mandatory while the whales are in the channel.

Click on the image for a closer view.

This particular individual seems to be carrying an egg sac. Some of the others are as well.

Ship Strikes Killed Blue Whales

Biologists at the Santa Barbara Museum of Natural History presented results of necroscopies of blue whales that washed up on local beaches last fall: the whales were killed by ship strikes. They surmise that the whales were in shipping lanes because the krill was there, and that the whales probably didn't hear the ships approaching, because they were directly in front or because of background noise.

Last fall, after the blue whale deaths, ships deliberately slowed to 10 knots in the shipping lanes; that may have given whales more time to get out of the way.  We'll see where the krill shows up this year, and whether the ships slow down.