One of our favorite family groups of transient killer whales have been extra present in the Salish Sea this August. Featuring two HUGE adult males and two adult females, the T18’s (named after T18 Esperanza). The T18’s are a unique little group of whales, not only because of their social structure but also because the oldest of the two males, T19B aka Galiano, sports a hefty dorsal fin that leans significantly to the left.
We spotted this family of four as they were crossing Haro Strait and aiming right at San Juan Island. Whales close to home, what a treat! Just a mere hop across San Juan Island from Friday Harbor, we were even fortunate enough to have Lime Kiln Lighthouse as a backdrop to this family’s antics. We watched as all four orcas traveled speedily and gracefully up-island, and got some incredible looks at just how floppy Galiano’s fin is compared to his brother Sprouter’s typical dagger-shaped dorsal.
Because orca’s dorsal fins don’t have any bone structure supporting them (they’re actually just 6 feet of pure cartilage and soft tissue in males), they are only kept upright by the water pressure around them. In the wild, orcas spend the majority of their time moving underwater, keeping those dorsals nice and strait. Dorsal fin collapse is common in captive males due to spending so much time above the surface, where their daunting dorsal will just fall down under its own weight. Rarely, thought, there’s a male in the wild that’s just so darn big that his dorsal gets a little bendy. Possibly Galiano spent a little more time than normal above-water when he was young and his dorsal was still solidifying, or possibly he’s lacking a little bit of cartilage in there, reducing the structural integrity of his fin even more. Either way, his unique dorsal makes him easy to ID, and doesn’t seem to hinder him in his hunts in the slightest!
We motored back home around the top of the island, completing a full circumnavigation of San Juan Island. On our way back to Friday Harbor we even had time to stop for harbor seals, land-dwelling ruminants, and bald eagles. What a treat of a day!
Check out (and feel free to download) photos of our encounter with Esparanza, Mooya, Galiano, and Sprouter below!
Naturalist Sarah C.
M/V Sea Lion