Whale Gymnastics: Tail Slaps
Tail slaps are another intriguing humpback behavior. Most obviously, they reflect the tremendous power the whales' tails can exert, but photo sequences also reveal something of the technique, akin to a baseball pitcher's winding-up process, that may achieve a more powerful slap by increasing the tail's speed before impact.
Here are three tail-slap sequences. The second and third sequences depict the winding-up process.
Here's a simple four-frame tail-slap sequence. Note that there is a second whale nearby. It is "waving" its pectoral fin, as seen most clearly in the fourth frame, past the slapping flukes.
This longer sequence shows a pre-slap wind-up, and the flexibility of the flukes.
Below is another wind-up and slap. The spray or water from the back-lit tail gives an idea of the flukes' angular velocity generated by the powerful peduncle during the wind up and then the downward slap.
Why do humpbacks sometimes tail slap? The Sea Goddess whale watching site states: "While there are many theories on why whales lobtail including attracting the opposite sex, aggressive posturing to ward off males, communicating with other whales, scaring prey, defense or play, a more plausible suggestion relating mostly to humpback whales, is a means of foraging."
Two of these possibilities might fit the behavior depicted in this post: play after successful hunts or as an adjunct to foraging, since the slaps might have helped corral prey on an afternoon the whales collaborated in bubble-net feeding.
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After a lifetime of mainly expressing myself with words, my postings here will mainly rely on images. They will speak for themselves to some extent, but I'll usually add a few comments of explanation. I've taken photographs for decades, since the 1950's, inspired in part by my father's photographic skill. Four years of photo assignments and quality darkroom time eventually gave way to decades of casual and family picture-taking. I re-immersed myself when I left film and turned to digital.