Monday, February 1, 2010

"The Humpback of Hilo Bay"

To Hawaiians, the whale is a representation of the Hawaiian god, Kanaloa – the god of fish, animals in the ocean and greenery on land. My wife (Devany) and I have recently become interested in the humpback whale since on most days we can now see off our lanai some ten to fifteen of them – often doing many incredible feats.

One thing humpbacks do is breach. This is when the whale lifts almost its entire body out of the water. It will turn its body while in the air so that it will land on its back. They may breach to remove parasites such as barnacles from their bodies. Other theories are that they want to take a look around, they are just being playful, or that they are trying to attract the attention of other whales.

Another thing they commonly do is tail slap. This is when a whale will hit the surface of the water with its tail in a slapping motion. It makes a very load sound although it is not quite known why they do this. Some have speculated that it is used by the males to either attract females or it is an aggressive posture to ward off other males.

And finally, there is fluke slapping. This is when the whale will raise one of its two flukes and slap it against the surface of the water. Researchers believe this is another aggressive posture toward other whales. It is also thought to be a method that the female whale uses to stress or enforce a lesson to her calf. mauicheetah

Humpback Whales show up in Hilo Bay from roughly Christmas to Easter. They make their annual journey from near Alaska to the waters surrounding the Hawaiian Islands. Here they mate and give birth to their young. You can often see babies which were just born traveling with their mothers and learning how to dive, and breach high into the air. Their annual migration of about 6,000 miles is one of the longest of any mammal.

Mother whales nursing their calves usually arrive first in Hawai'i. Then juveniles and newly weaned yearlings come. The adult males arrive next, double the number of adult females who follow. Finally, the pregnant females arrive, after feeding up to the last minute in Alaska.

Humpback whales are the fifth largest of the world's great whales; a mature whale can be up to 45 feet long and weigh about 42-45 tons. Even their tongues can weigh up to one ton!

The calves have a ten to twelve-month gestation period. On average, newborns weigh 1.5 tons and are 10-16 feet long. New born calves grow at the rate of about 100 pounds a day strictly from the milk they receive from their mothers.

Humpbacks are distributed throughout the world's oceans, although all populations were depleted by whaling from the mid-1800s and into this century. As many as 15,000 humpbacks may have once been present in the North Pacific, but the numbers were reduced to less than 1,000 animals by 1965.

Today however the whales are doing better, according to David Mattila, science and rescue coordinator for the Hawaiian Islands Humpback Whale National Marine Sanctuary. His study co-authored in 2006 concluded that about 10,000 humpbacks winter in Hawai'i waters. The study also calculated that their numbers are increasing by about 6 percent to 7 percent each year.

At that rate, there now could be 12,000 or more humpbacks here each winter -- a very positive sign.

We can hear them slapping and sometimes groaning and of course they are famous for their underwater songs – but I’ll “save” that for another posting. Aloha.

1 comment:

  1. Interesting! Thanks Wes. As always I learn a lot from your posts.


Mahalo for leaving a comment!~WesIsland