NGOS News

June 2008

This is a “La Nina” year which brings cold water temperature and stormy and rainy conditions to the Gulf of Alaska and Aleutian Islands. It also brings upwelling nutrients and productive conditions. It makes our work more difficult: we had freezing temperatures and howling winds in our recent spring season around Unimak Island and False Pass in the eastern Aleutian Islands.

Despite weather difficulties we were able to photograph eighty six different individual transient killer whales as they pursued and fed on the migrating gray whales headed for the Bering Sea. Many of the whales like “Floppy”, whose fin is folded down on his back, and “Per” who has a bit of disheveled appearance, we saw repeatedly when groups of up to 50 killer whales fed on gray whale carcasses that lay on the bottom in shallow waters.

Listen to calls:  sample 1  sample 2  sample 3

Gray whales are generally killed by small groups of 4-7 transients, but many other killer whales may participate in what appears to be a complicated sharing arrangement between the different killer whale groups. Certainly the group that kills seems to get the first good feed on the carcass, but typically they make calls that eventually bring other whales around. A small group of killer whales can only consume a small portion of a gray whale calf or yearling before they are full. It would make sense to share and then take part in the kills made by others. However, there seems to be a system of taking turns, certain whales seeming to have more access to a carcass than others, perhaps based on how they are related to the whales that made the kill. Our team watched this year as one female was roughly butted and driven away from the carcass. The whales are not always generous! Often there are a number of whales that hang on the periphery seeming to wait their turn.

Killer whale with a blubber blanket.

We saw some massive “blubber blankets” this year. These are large chunks of blubber that the killer whales rip from the gray whale carcass. Being buoyant, they tend to float to the surface. This year some measured over 12 feet long and 4 feet wide. One had the bumpy dorsal ridge of the gray whale visible down the back, so as it floated it almost looked like a gray whales was surfacing... Only there was no body attached! Think of how difficult it would be to tear these extremely tough, fibrous blubber layers into pieces when they are not attached to the carcass, but floating free. We assume the whales must take ends of the piece and somehow pull against each other like a tug of war, but we have never seen this. The whales typically take the chunk back below the surface to work on it. And also think of the force it takes to tear these layers of blubber off the carcass! We would love to see what is going on below the surface...

Although migrating gray whales are the reason for all these transients to assemble, they may consume other marine mammals while here. We watched a group of four kill a harbor porpoise (only about 5 feet long) and consume it in about 10 minutes. There was a short chase by one of the whales, another joined in and soon it was all over but the sharing of the carcass among the group.

We see a few new calves each year, but it seems the rate of recruitment of new transients is relatively low. Despite that it seems the whales have an endless banquet at this time of year, and it is probably much more difficult to make a living when the large gray whales are gone. Also, many killer whales have nicks and healed cuts that suggest a difficult existence in these cold northern waters.
 

In early June we were back in Kenai Fjords waters where we began our season a bit late (10 June) after continual spring storms and 50 mph winds made work nearly impossible in early May. We spent one afternoon with the AD11 matriline, led by Aurora (AD11). This is a part of AD pod that we did not see last year. It seems strange that AD11 does not swim more often with her sister, AD8, the leader of another matriline in this pod, but although they are both swimming in the same waters, they seem to make an effort not to intersect frequently. Is this the result of some long-running family spat? We did see both matrilines together for some brief socializing. The four whales in this group were accounted for, but there were no new calves. The young male Angiak (AD27) has grown a nice dorsal fin and he swam repeatedly across our bow as if to show it off. Nice to see these friendly resident (fish-eating) whales after spending the past weeks with the rough and rugged transients of the Eastern Aleutians.

Day after day in early June in various order the same 20 whales, the AD8 matriline, AD11 matriline, and the AK2 matriline (half of AK pod) swung into the Agnes Cove and Porcupine area of Resurrection Bay to chase Chinook or King salmon near the shoreline. These are extremely friendly whales that often approach our boat as well as the stream of tourboats that also come to watch. The tourboat operators love these easy going whales and their constant presence in the spring insures happy visitors and tour operators as they watch whales like the playful Capra (AD31) and brother Tatitlek (AD35) swing back and forth under the drifting boats. The AK pod whales always end up nearest shore and seemed to practically camp out in Agnes Cove for a couple days. Why do these beach rubbing AK whales love the near shore so much? We watched one evening from the kayak as they pinned salmon against the rocky beach in the deep reaches of the cove, their explosive exhalations startling us as they rocketed by the kayak. One fish got lodged up in a rock crevice where the whales couldn’t go and a Steller sea lion swam in and grabbed it. When he emerged, we paddled toward him and he jerked the fresh caught fish below the surface, keeping it out of our reach.
 

In mid-June, we headed across the Gulf of Alaska to Prince William Sound, hoping to encounter the AT1 transients or some of our other resident pods. Based on previous experience and the tracks of tagged animals in past years, we decided to travel 70 miles east to Hinchinbrook Entrance. Luckily, we had a spell of calm weather; otherwise, the exposed and tide-ripped waters of Hinchinbrook make work in a small boat treacherous. We hoped in particular to find AB pod and AJ pod, who seem to use the Gulf of Alaska waters outside the Sound at this time of year.

Sure enough we found our whales... Part of AJ pod, AB pod, the AX48 pod, and AI pod were all mixed together in a “superpod” aggregation that we followed for 10 hours (and over 30 miles) along the outside coast of Monatague Island in the Gulf of Alaska. We observed a lot of socializing and resting with more than seventy killer whales spread out for miles; photographing every whale was a real challenge. We managed to attach small satellite tags to AB45 and AJ 21 before the long day ended just outside Patton Bay, halfway down Montague Island. Lighting conditions were perfect for photographs and there was very little swell and no tourboat traffic along that wild stretch of Alaskan ocean.

A spy-hopping killer whale

Killer whales socializing

The next day, we traveled seventy miles back into Montague Strait, in anticipation of worsening weather. South of Little Green Island, we spotted blows and fins from a small group of killer whales. As we sped toward the whales, the possibilities ran through our minds: transients? AI pod? There were only four individuals, rising in synchrony, slowly traveling north. We paralleled them and soon identified the AD11 matriline. Apparently, the salmon feeding frenzy in Kenai Fjords had ended. We wondered if they’d joined with the previous day’s superpod south of Montague Island earlier in the day. As usual, we were left with plenty of tantalizing questions to ponder as we headed toward a secure anchorage for the night.

Read the past news updates for 2001, 2002, 2003, 2004, 2005 and 2007.