Wednesday, February 9, 2011

Moon by Whale Light: Whales

Photo: Flip Nicklin, National Geographic.

The following video has very interesting audio, but no visuals. I suggest listening while reading this posting.

For the third chapter of Moon by Whale Light, Diane Ackerman spends her time with whales. To meet with Roger Payne she goes first to Hawaii to listen to Humpback whales singing and then to Patagonia to study Right Whales. It was Payne who discovered Whalesong in 1967 and he has been working on theories for its purpose ever since. But little is known and whales are very difficult to study. Various theories include singing for territorial designation or for attracting a mate. It is supposed that only male Whales sing, but it is not even known how they sing. the songs are monotonous over a period of time, but change from year to year with different sounds being exchanged for one another.

Humpback Whales are a migratory species, spending the summers in cold, nutrient rich waters and migrating to warmer waters to give birth. Because of the vastness of the oceans it is very difficult for scientists to track the movement of these and other whales. After giving birth the female will not be able to feed in the tropical waters, she must wait until her calf is mature enough to travel to feeding grounds in colder climes. The calf grows very quickly, nourished by her rich milk.

For a gallery of other photos and sounds Whale Trust is an excellent resource. They also publish some beautiful books.

Ackerman meets with Roger Payne again in Patagonia, a stopping point for the endangered Right Whale on its migration to feed in the waters off Antarctica. They stop along the coast to engage in courtship and raise their young. Ackerman joins Payne and other researchers at the rustic station that he has set up there overlooking two bays that are frequented by whales.

The Right Whale is a Baleen Whale or Mysticeti, like the Humpback. They have no teeth but hundreds of closely packed, springy baleen plates that they use to filter out small prey such as krill, plankton and small schooling fish. They also have two blow holes in the top of their heads. Toothed whales (Odonoceti) such as orcas, sperm whales and dolphins only have one and echolocate to find larger prey.
Southern Right Whale photographed by Brian Skerry.

Right Whales earned their name in a rather macabre way. They float when dead and where referred to as the 'right whale to kill' by early whalers. It is the rarest whale species, hunted almost to extinction. It is however a surface whale making it easier to study and observe. The mating of Right Whales is far more aggressive than other documented whale species. Little is known about the mating of other whales because it has not been seen. Right whale "courtship" takes place on the surface and is a riotous affair with several males to one female. The females breed every three to five years and the calves are weaned after 8 months to a year. Adolescent whales have been seen following mothers and calves and it is theorized that they may be from the previous breeding season.

Ackerman swims with a mother and calf and observes how gentle and calm they are in her presence. The young one swims very close to her but she does not touch it as it can be very dangerous to startle a whale. The calf weighs a metric ton and may not know its own strength. Casualties from Right whales have occurred when boats have been crushed accidentally by tails or fins. The following photograph by Brian Skerry for National Geographic illustrate how close one can get to these giants when careful.

For some other inspiring whale stories here are audio podcasts from Radiolab and Stuff You Missed in History.
The introduction to Radiolabs Animal Minds is a story about a rescued whale off the coast of San Francisco.

The post from Missed in History is the story of a Sperm Whale turning the tables on a whaling ship. And is available through Real-Life Moby Dick.

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