February 2, 2024
We really wish you had been aboard for Thursday’s Mid-Morning Whale Watch Cruise from Kawaihae Harbor (and if you were aboard, we applaud your decision).
We hadn’t even left the harbor entrance when we spotted our first spouts, and we were only out of the harbor for a few minutes before a couple of Humpbacks spouted close to our bow. While we were watching these whales, getting great views of the tubercles on their faces, another 2 Humpbacks completely surprised us by breaching simultaneously just about 200 yards off our port rails.
We spent the rest of the trip “bouncing” between other Humpback duos. One duo was comprised of Momma and her calf, but we also spent some time watching a pair of adults (who based on their relative sizes might have been Mom and her yearling — last year’s calf). This “maybe-yearling” was doing something we hardly ever see — she was lifting her flukes up in the air and then very lazily sinking back underwater. What was that about? See today’s Fact of the Day for our best guess. While we were watching this unusual behavior, we deployed our hydrophone and heard from a lot of other whales in our area, and we also got to see some breaches from other whales a bit further away.
Ocean Sports Whale Fact of the Day: Why would a Humpback stick a body part up into the breeze? During prolonged exercise in warm water, a Humpback’s body will generate heat — the same thing happens to you when you’re exercising — but you’ll start sweating to cool down. Humpbacks don’t have sweat glands, and since they have some control over their circulatory systems, as they heat up, they can direct blood flow into a network of capillaries near the surface of the their flippers, flukes and dorsal fin (in Latin these capillaries called “retia mirabilia” which translates to “miracle network”).This in turn allows the excess body heat to be shed to the external environment through evaporation and convection. So many researchers believe that whales who are resting with their flukes exposed vertically in the air, or lifting their pectoral flippers for prolonged periods of time are actually trying to cool off.