March is proving once again to provide remarkable opportunities to witness the humpback whales on their Hawaiian breeding grounds.  Many of the recent sightings have been of larger groups of whales, where males are thought to be competing with each other to gain access to the female.   In other species of whales, males cooperate with each other to mate, but in humpback whales competitive mating groups dictate which male will prove most likely to mate the female.  These larger groups of whales, also called “chase groups” are especially entertaining to watch as males often display in an effort to intimidate one another; they are sometimes seen hitting their huge 800-pound tails on the water, slapping their 15-foot long pectoral flippers, or raising up and lunging their massive heads above the surface, blowing bubble trails to obscure the visibility of fellow competitors, or even launching their 60,000 – 80,000 pound bodies out of the water creating a thunderous splash.   These impressive behaviors are part of a strategy intended to secure the position closest to the female who likely will be receptive to mating the most dominant male.

 

While humpback whales are in Hawaii seasonally, there are a variety of whales and dolphins that live here year round.  Frequently these “residents” are seen interacting with the seasonal visitors.  Last week, we witnessed an encounter between pygmy killer and humpback whales.  Pygmy killer whales are amongst the smallest of the whales, but what they lack in size they make up for in attitude.  Often seen waiting outside of tuna fisheries for dolphins to escape the nets, pygmy killers have earned themselves an aggressive reputation.

Also seen interacting with humpback whales are sometimes curious pilot whales.  Witnessing the co-mingling of interspecies encounters is always thrilling.  In fact, just last week while waiting for a humpback whale to surface, we had a group of exotic Cuvier’s beaked whales come up near by.  Cuvier’s are rotund in shape, mostly white in coloration, characterized by a lot of scarring and have a single barnacle laden tooth that protrudes from the tip of the jaw that resembles a clown nose.  Some of the most unusual species in the world’s oceans, Cuvier’s beaked whales are the focus of a lot of study over recent years as they are often implicated in strandings following naval sonar exercises.

 

The bottlenose, spotted, and spinner dolphins are also frequently seen with humpbacks.  These resident dolphins can be seen jumping over the backs of humpback whales or even riding near the face of the whale in a similar manner to riding the bow of a boat where they take advantage of the pressure wave the whale creates as it moves through the water.

 

 

Aloha,

Captain Dan

 

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