This summer I finally got the opportunity to spend a week with a group of researchers in San Diego. Mari Smultea and Bernd Würsig have been bringing a small team to San Diego since 2009 to fly aerial surveys off the coast of San Diego in order to collect baseline data on the distribution, density and behaviour of marine mammals.
Project lead, Mari Smultea
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Cloudy skies
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me, happy to be observing
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Mari invited me to join them for their final survey of 2013 so that I could have the opportunity to learn about how cetacean behaviour data are collected from aircraft. Mari and I are both working with these types of data for our doctoral research, but unlike Mari I have not yet had the opportunity to see first-hand how behaviour data are collected from the air because my data mostly collected in the 1980s. So when Mari emailed to see if I wanted to join her and the team this July I jumped at the chance. Not only would I get to fly with Bernd Würsig –a leading expert in the study of cetacean behaviour and who was the first to define the different bowhead whale behaviours and collected the bowhead behavioural data that I have been using in my research, but this was my second chance this year to see the blue whale. The largest animal to have ever lived on this planet.
If you have read my earlier posts you may remember that my first real attempt to see a blue whale was back in April when I went out on a whale watch trip in Monterrey Bay. This quest was scuppered by killer whales. But this time round in San Diego my chances were better, or so Mari assured me. I was optimistic, especially after the team returned from their first flight of the survey to report that the blue whales were around just off the coast of San Diego. They came back that first afternoon having seen a number of blues that meant they were able to conduct focal follows on at least 2 whales.
If you have read my earlier posts you may remember that my first real attempt to see a blue whale was back in April when I went out on a whale watch trip in Monterrey Bay. This quest was scuppered by killer whales. But this time round in San Diego my chances were better, or so Mari assured me. I was optimistic, especially after the team returned from their first flight of the survey to report that the blue whales were around just off the coast of San Diego. They came back that first afternoon having seen a number of blues that meant they were able to conduct focal follows on at least 2 whales.
Dr. Bernd Würsig observing from the plane To conduct a focal the team will circle the whale from an altitude of 1500 ft if cloud conditions allow. They record the behaviour of the whale including the time it blows, when the tail is seen to rise out of the water –known as fluking, the time the whale dives and how long it dives out of sight for, which direction the whale is headed in, how fast it is moving and the general activity state of the whale (e.g., travelling , foraging or resting). All these data are recorded onto audio and video recorders and the whale is photographed as well. Later, these data are transcribed and scrutinized to ensure that everything is entered into the survey database.
For the first part of the survey I was able to help the team with various data tasks including examining sets of photographs collected during focal follows on the blue whales seen. Mari and Bernd were keen to confirm that a whale observed during an hour long observation session was indeed the same whale. I poured through photo after photo from three photo sessions that had been taken during the focal follow looking for a scratch or scar that would make matching the photos possible. Then there it was a ding on the left shoulder of the whale –a scar likely resulting from a cookie cutter shark. I was able to match photos from each of the photo sessions confirming that they had indeed been circling over the same whale. By the end of the second day of the survey I had performed photo-ID on a blue whale from photos taken at more than 1000 ft but I still had not seen a blue whale in person.
For the first part of the survey I was able to help the team with various data tasks including examining sets of photographs collected during focal follows on the blue whales seen. Mari and Bernd were keen to confirm that a whale observed during an hour long observation session was indeed the same whale. I poured through photo after photo from three photo sessions that had been taken during the focal follow looking for a scratch or scar that would make matching the photos possible. Then there it was a ding on the left shoulder of the whale –a scar likely resulting from a cookie cutter shark. I was able to match photos from each of the photo sessions confirming that they had indeed been circling over the same whale. By the end of the second day of the survey I had performed photo-ID on a blue whale from photos taken at more than 1000 ft but I still had not seen a blue whale in person.
The next day I got to fly. It was a short training flight and though I was optimistic we did not find any blue whales. We flew again the next day and saw many mola mola, common dolphins and even a group of bottlenose dolphins, but still no blue. The fifth day of the survey dawned, again the weather was not promising, but there was less cloud that the day before. We set off to search for blue whales along the coast. Again we saw lots of mola mola and common dolphin but no blues. Heading south towards the border with Mexico we saw more common dolphins, circling groups to confirm species, estimate school sizes and document behaviours. We observed interesting behaviours such as synchronized upside down swimming followed by rapid darting manoeuvres in different directions. We saw groups of three to six dolphins do this at a time while in front of the main school. This behaviour was indicative of foraging –the dolphins appeared to corralling and chasing fish.
As we continued on we saw a group of Risso’s dolphins; Mari is studying the behaviour of these dolphins for her PhD and has observed Risso’s with other dolphin and whale species. This time we saw them alone but were able to observe apparent social behaviours and surface active behaviours. These dolphins are much larger than common dolphins and very light in color due to the scaring that covers their bodies, not much is known about them in the Pacific so these surveys provide a unique opportunity to study them.
As we continued on we saw a group of Risso’s dolphins; Mari is studying the behaviour of these dolphins for her PhD and has observed Risso’s with other dolphin and whale species. This time we saw them alone but were able to observe apparent social behaviours and surface active behaviours. These dolphins are much larger than common dolphins and very light in color due to the scaring that covers their bodies, not much is known about them in the Pacific so these surveys provide a unique opportunity to study them.
We continued on our search for blue whales, following the edges of undersea canyons. We slowly made our way out to San Clemente Island and picked up more dolphins. Suddenly Bernd called out “whale”! Was this going to be my first blue? I saw the large rostrum of a baleen whale disappear beneath the surface –we circled back to pick it up as it surfaced but 12 minutes later there was still no sign of the whale. We continued on our way left wondering whether the whale had been a fin, sei or Bryde's whale. There was only one more day left on the survey and I was beginning to wonder if I really was going see to blue whale. Had I been slunk again?
We turned back for San Diego. Then there it was. A blue whale hanging there, seemingly suspended just below the surface. The whale glowed a beautiful turquoise blue color in the water. As we circled to document the sighting, my eyes were glued to the whale, watching and waiting for it to rise to the surface and blow. It hung there still, barley moving, then as the pilots turned back towards our track-line the whale rose majestically to the surface and blew. I watched the blue whale disappear out of view behind the plane. I had finally seen a blue whale and the image of this magnificent great whale hanging so gently below the surface was burned into my memory.
We turned back for San Diego. Then there it was. A blue whale hanging there, seemingly suspended just below the surface. The whale glowed a beautiful turquoise blue color in the water. As we circled to document the sighting, my eyes were glued to the whale, watching and waiting for it to rise to the surface and blow. It hung there still, barley moving, then as the pilots turned back towards our track-line the whale rose majestically to the surface and blew. I watched the blue whale disappear out of view behind the plane. I had finally seen a blue whale and the image of this magnificent great whale hanging so gently below the surface was burned into my memory.
The final day of the survey resulted in 155 sighting in 4 hours, common dolphins, California sea lions chasing bait balls, mola mola, and more Risso’s dolphins, we didn't see any more whales despite almost perfect sighting conditions but I was happy, I had seen and learnt so much, worked with a great team of people and above all I had finally seen a blue whale.
Blue whale fluke breaking the surface
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