May 26, 2015

Transients and Dall's and hybrids, Oh my!

We started this trip with smiles on our faces because of the warm weather, and ended it the same way because of the spectacular wildlife we encountered. With no orca reports when we left the dock, we headed North to try our luck. On the way, we spotted an abundance of harbor porpoises, their tiny dorsal fins rolling at the surface as an indication of their presence.

Much to our delight, we soon received notice of two transient orcas between Saturna and South Pender island near the Java islets. There, everyone on board was able to get a great look at the individuals. Remember that transient orcas are mammal eaters, and we suspect that some of the erratic, sudden movements that we observed today may have been them making a kill! Based on their distinct dorsal fins, we were able to ID them as T077A and T124C, two unrelated males. This was a great example of the more fluid social structure that transient orcas are known to have, as compared to residents which stay in their maternal family group throughout life. It would be very unlikely to see two unrelated resident males both without their mother. However, we have no doubt that these boys that were hanging out today will eventually regroup with their more immediate family.

As if everyone on the boat wasn't excited enough to have seen the transients, we then came across some Dall's porpoises off of Stuart Island. These porpoises can swim up to 36 miles per hour, thanks to their streamlined shape and incredibly powerful peduncle muscles. They also move so fast and breath so powerfully, that they barely break the surface to breath, and therefore create what's called a "rooster tail," which is a big spout of water and air (that resembles the extravagant tail of a rooster). AND as if THAT wasn't enough, Captain Mike spotted and pointed out a hybrid porpoise--the offspring of a Dall's porpoise and harbor porpoise. It has the shape of a Dall's, but coloration that more resembles harbor porpoises. This is a fairly new discovery in the scientific community, so the fact that everyone got a good look at one had me almost in tears!

We also got a great look at some harbor seals, a Stellar sea lion, and even some mating Bald Eagles--which are known for mating in very synchronous flight. All of this combined with the great weather made for an awesome day on the Sea Lion.

 

Naturalist Alex

M/V Sea Lion, San Juan Safaris