A few weeks ago, a subadult Humpback whale was sighted off Na Pali Coast, floating stationary in the water, head down, the tip of its fluke visible above the waterline. At first, boat crews were concerned the whale was injured or entangled, however, no entangling gear was present, and no wounds were visible. During the ensuing weeks the same whale (confirmed by photographs of its fluke and various body scars) was seen in the same position–fluke just visible above the waterline–close to shore near Port Allen, Makahuena Point, Anahola, Kipu Kai, and in Hanamaulu a mere 30 yards from the pier. Dennis Fujimoto took photos and wrote this short piece in TGI.
Jamie Thomton, Kauai Marine Mammal Response Coordinator with NOAA, observed the whale and reported it was is in good body condition with no signs of injury. Its pattern of behavior was to pose in a vertical position for about 10 minutes, then back to normal logging/breathing position for 10 minutes, repeat. There have been no further sightings.
Turns out, this behavior, while rarely seen in Humpback whales, is common in Southern right whales, according to this article in the UK’s Daily Mail, and it’s called “tail-sailing.” Scientists aren’t 100 percent certain why whales tail-sail, but it could have something to do with thermoregulation, suggests Ed Lyman Ed Lyman, Resource Protection Specialist for the Hawaiian Islands Humpback Whale National Marine Sanctuary, is quoted in the article. But, he says, it’s not necessarily a posture for navigation as the word, “sail” may indicate.
This is just a reminder that there’s much we don’t know about marine mammals. It’s always good to report unusual behavior. In this case, while unusual, it was normal.
Kaua'i Seals 