Thursday, July 31, 2008

Blue Whale Fest

On July 26th, LK and I went out on the American Cetacean Society's Blue Whale Watch, a fundraising trip aboard the Condor Express. We ventured out about 26 nautical miles from the Santa Barbara harbor. It was a blast! We had perhaps a thousand Short-beaked Common Dolphins, two Minke Whales, and ultimately, at least ten, but perhaps as many as twenty Blue Whales. As we approached the waters that the Blue Whales had been favoring, the fog grew thicker until we were unable to see more than 100 meters from the boat. I began to worry a bit that we might conceivably miss them due to fog, as I have had some difficult whale watching experiences on the Bay of Fundy thanks to fog. Eventually, it was the skipper who heard one blow over the noise of the engines. We idled at the spot until we again heard the loud and unmistakable spouting. We crept toward the sound until finally we could just barely make out the slightly darker form of a whale at the surface. We followed it slowly, getting progressively better views until it led us into less foggy conditions. From this point on, we were never out of sight of whales. This was about 7-8 nautical miles WNW of Santa Cruz Island (see map). I had seen Blue Whale on three other occasions, but the opportunity to spend more than three hours observing these magnificent creatures was simply fantastic.

The seas were wonderfully calm for our excursion. There seemed to be a lot going on at times, with numerous California Sea Lions visible for much of the trip. There were a couple of Harbor Seals seen too, including one wrapped up in kelp. It wasn't doing any talking. There were a few Ocean Sunfish, and at one point, we found a small gathering of young ones. Seabirds were sparse, though there were plenty of Sooty Shearwaters and smaller numbers of Pink-footed Shearwaters.

The trip's narration was first rate. Most of it was delivered by cetacean expert Alisa Schulman-Janiger. Among the myriad of whale trivia she mentioned over the course of the cruise was that recent tagging/tracking studies of Blue Whales had shown that Blue Whales seem to form male-female pair bonds, as animals are often found in pairs with the female swimming just ahead of the male. Unlike the toothed whales, baleen whales are not thought to form any significant long term social bonds outside of that of a mother and calf. So the long term pair bonding of Blue Whales is a significant finding. We also encountered a team of cetacean biologists (working under Dr. Bruce Mate) who were tagging Blue Whales, and we were able to observe two of these tagged animals.

The occurrence of Blue Whales in the Santa Barbara Channel in summer seems to be a recent phenomenon. When I was at school at UCSB in the mid-80's, Blue Whales were almost unheard of near the Channel Islands. But beginning in 1990, small numbers began to arrive in summer to feed on a couple species of krill that have been gradually increasing in number. By 1993, whale watching tours were making regular trips to see these magnificent animals. According to Schulman-Janiger, the 2000 or so Blues that spend the summer off of Santa Barbara represent the largest known population in the world, and one of the few that seems to be growing. Satellite data has demonstrated that many of these whales go south as far as the Pacific waters off of Costa Rica. 

One final gee whiz.  Male Blue Whales have one of the loudest voices in the animal kingdom.  We just can't hear them.  Their sonorous booming is too low pitched for human ears.  This site has an example of the sound sped up 10 times to bring it into the audible range. It can be heard across vast distances.  Researchers have recently noted that in the last few decades, the frequency/pitch of the Blue Whale vocalizations has dropped, (i.e., calls are lower pitched today). No one knows for sure why that it, but some speculate that it is increased competition for mates as their populations rebound. More in this New York Times article.   

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