Interesting Facts about Whales

Scientists believe that early whales actually walked the earth. The theory, supported by recent fossil finds in the foothills of the Himalayas, is that about 53.5 million years ago, whales were amphibious. They originated as land mammals, and gradually ventured into the water in search of food. They fed on fresh and saltwater fish. Eventually, they lost their legs and nostrils, and became the creatures we know today.

The name of the early species is Himalayacetus subathuensis.

Source: New York Times Science Times, Tuesday, January 12, 1999

Domino effect: The sea otter population in the Aleutian Islands has declined by about 90 percent, and this change is due to a disturbance in the web of marine life. Ecologists who noted the disappearance of the otters in the early 1990s discovered that orcas (killer whales) had started eating the otters. This is a new development in what was always a peaceful relationship between orcas and otters. In a recent issue of the journal Science, a team of scientists gave a detailed explanation for this change: sea lions and harbor seals have been the standard orca diet, but due to a sharp decline in their most nutritious meal, ocean perch and herring, their populations have declined. So, the theory goes, in lieu of sea lions and harbor seals, orcas are going after the next best thing: sea otters. The decline in the forage fish population has several possible causes, including over-fishing by commercial fishermen, and warming of the Northern Pacific climate.

Source: The New York Times Science Times, January 5, 1999

Scientists have determined that killer whales can live a maximum of 35 years. How? By looking at a cross-section of a killer whale's tooth! Killer whales, like other marine mammals, produce a periodic growth layer on the teeth. By counting these layers, scientists can estimate the animal's age.

Source: WhaleTimes Website

Marine mammals such as whales and dolphins spend their entire lives at sea. So how can they sleep and not drown? Scientists have observed two basic methods of sleeping: They either rest quietly in the water, vertically or horizontally, or sleep while swimming slowly next to another animal. Young whales and dolphins actually rest, eat, and sleep while their mother swims, towing them along in her slipstream. This is called "echelon swimming." At these times, the mother will also sleep on the move. In fact, she cannot stop swimming for the first several weeks of a newborn's life. If she does for any length of time, the calf will begin to sink; it is not born with enough body fat or blubber to float easily.

Source: South Carolina Aquarium

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