by Dr. Kayla Causey

I keep thinking that these trips just can’t get any better. And then they do. Yesterday was no exception and was really an example of how mother nature continues to raise the bar for the Gray Whale Foundation this season.

First of all, San Juan Elementary students (we had 3 classes total; 100 students) were well prepared and well behaved during their trip today. It was a real pleasure to work with them and their teachers.

We set out from the dock aboard the Dana Pride at 10:22 a.m., with the tide moving out, the seas smooth, skies clear, and the water 63 degrees (Beaufort State was 1). We were barely out of the Harbor when we sighted Pacific White Sided dolphins (lags). These lags were particularly friendly and stayed with the boat bowriding for about 15 minutes. It was a real treat for the scholars to see these unique and beautiful creatures. But the truly unique experience was still to come…

At around 10:44, we received a call from Capt. Mike at the Ocean Institute, saying that he was with, what he thought was, a large pod of pilot whales. We all thought, “Pilot whales?!” We knew this had to be something totally rare. So we headed down the coast to investigate. As we approached, there were already several other boats in the area. Capt. Todd called Alisa Schulman-Janiger, the director of the ACS-LA Gray Whale census (which you can follow here: http://www.acs-la.org/), and a long-time cetacean expert of Southern California. We wanted to alert her to the sighting and find out whether she could recall the last time that Pilot Whales were sighted in Southern California. As Capt. Todd described what we were seeing, and as we all watched the fast-moving animals in front of us, we all came to the conclusion that these weren’t pilot whales, but false killer whales (Pseudorca crassidens). Amazing! And also a rarity in the area. We later learned that the last sighting of false killer whales off of Southern California was in 2001.

There were about 40-50 animals in the entire pod, but they stayed in smaller, tightly-clumped subgroups of about 10 individuals. False killer whales are known for this tight social structure – they often share food, and the close physical contact help them stay in sync with one another during foraging bouts. There were several calves present, as well as larger adults. These toothed whales moved in amazing synchrony, often surfacing in rank formation. They surfaced so close together that there was often body contact and pectoral rubbing, which you can see in some of the images below.

We saw a few instances of fluking prior to a deeper/longer dive, some chasing behavior later on down the coast (which suggested feeding was occurring), evidence of feeding (check out the photos above of the false killer whale with a ~40 lb. white sea bass in its mouth!), and some breaching and leaping behavior as well. The whales seemed largely uninfluenced by the boaters.

Our track is pictured below, as well as the coordinates were we caught up with the whales. You can see that they traveled Northwest (up coast) in almost a straight line parallel to the coast. We remained in about 22 fathoms of water the entire way.They traveled briskly as well, averaging about 7 knots (about 7.7 mph).

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False killer whales are the third largest oceanic dolphin, and they’re called “false killer whale” because they resemble killer whales in behavior, movement, and feeding habits. Like orcas, false killer whales (FKWs) have a reputation for attacking and killing other cetaceans. I can’t help but wonder if their occurrence has anything to do with the dwindling number of gray whale sightings this past week. It’s so unusual to see FKW on our coast because they usually prefer warmer waters offshore (tropical, pelagic water). Below is an image of a captive false killer whale next to a bottlenose dolphin. You can see the relative size difference.

I heard a rumor that this same pod was sighted in Baja and Ensenada early on in the week, but I have yet to confirm. Researchers at Southwest Fisheries Science Center (NOAA) are very interested in the occurrence of these animals off our coast, so I will be busy editing images of dorsal fins to pass them on so they can use them for photo-id. Below is a sample of what I have so far. How many unique individuals can you count?  How many can you match? Although false killer whales are not the taxa that the Gray Whale Foundation studies, it is amazing to have the opportunity to contribute some data to others and to have had the opportunity to document such a rare occurrence with students aboard.

Perhaps even more intriguing, one of the whales had a deformity that was very similar to a deformity I saw in a coastal bottlenose dolphin (Tursiops truncatus) back in October, 2013 (see photos below). At that time, I sent the photo to other dolphin researchers and marine mammal veterinarians up and down the coast. There were several interpretations of the deformity, including that it was the result of a healed injury (possibly from boat strike or entanglement) or that it was a congenital deformity (similar to scoliosis). In the end, the consensus was that the deformity was perhaps congenital (the dolphin had been born with it). I think this instance of an almost identical deformity in a false killer whale makes for an even stronger case that this is the result of a congenital abnormality.

Our data sheets for the day are below. I’m sure there will be lots more to share as we receive reports and updates from others. By now you’ve probably seen the videos flying around the web. Check out this GoPro footage by Capt. Dave — It really highlights the curiosity of this species. Stay tuned, and follow us on Facebook to keep up!

 

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