July 8, 2020

A huge Group of Bigg's Orcas Scared off by Some Surprise Southern Resident Killer Whales!

Bigg's Orcas

Today we had another trip on our adventure boat, M/V Kestrel! It was another stunning summer day in the San Juan Islands. We had blue skies, calm seas, and a light breeze. Capt. Brian and I took a group of guests out to go search for some amazing wildlife in the Salish Sea! There had been reports of Southern Resident Killer Whales on the west side of San Juan Island and a report of some Bigg’s (Transient) Killer Whales east of us in Rosario Strait. These types are both orcas but have been separated for thousands of years. They speak differently, they hunt different prey, they have slightly different social structures, and they actively avoid each other. Since they choose not to interact and interbreed. They are two distinct groups like different species, but we can them ecotypes. A major difference between these two groups are their prey. Southern Residents (SRKW) fed on fish, 86% of which is Chinook Salmon while the Bigg’s feed on marine mammals – mostly Harbor Seals. It’s great to see either type. They behave differently and even look a little different. Another major difference is their populations. The SRKW population is declining due to a lack of their main food source, salmon while the Bigg’s Orca population is increasing at probably the quickest rate that they possibly can.

            We decided to go east to look at the Bigg’s Orcas! We took Kestrel through Upright Channel, through Peavine Pass and into Rosario Strait. Our other boat, M/V Sea Lion was watching the group so we headed towards them. Just as we started to slow down to watch these whales one of our passengers at the bow saw another group of orcas headed west towards the Peapods! We started to watch the whales near our other boat and there was a bout a 11 of them. But then there was another group that we saw right off our bow and another group far off our starboard. This was the most orcas that I had seen in a long time. We thought that these groups were going to meet up since they were swimming right towards each other, but they did the opposite! The biggest group of Bigg’s Orcas took a hard right to hug the Sinclair Island shoreline while the one off our bow kept heading south with no change in our path. At the time we didn’t know it but this was a small group of J pod (southern Resident Killer Whales) and the Bigg’s had grouped up tight and avoided the residents like it was their jobs! We do not often get to see the two ecotypes interact, but this is usually what happens, no matter how many of each type there are: the Bigg’s Orcas swim quickly away from the residents. We followed the huge group of Bigg’s and watched them travel through a kelp forest and slowing travel east. We got some great look at one of the families, the T37s, whose matriarch has a pretty, large dorsal fin for a female. We also saw some of the super cute calves popping their heads up! They had grouped up very tight after seeing the residents and it was so cool to see all their fins surface in unison. We got a few more great looks at their glittering fins as they continued their journey into Bellingham Bay. We turned towards home and got to stop by the Pea Pods and see a huge group of Harbor Seals sunning themselves on the rocks. We are glad these are here since they are the main food source for those Bigg’s Orcas. After looking at their fuzzy faces we saw a Bald Eagle perched on top of one of the rocks, waiting patiently for another animal to catch some food so he could then go steal it. After that we headed home with rhinoceros auklets and cormorant flying by. What another magical day in the San Juans.

Stay Well,

Naturalist Erick