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Actually, we don't think we ever saw this whale alive. It was a young, male, humpback whale which came into Cape Cod Bay in late May of this year. Fishermen reported seeing this whale very close to shore for about a week prior to its stranding, but these reports were not confirmed. On Sunday, June 3, however, this whale was found beached at low tide on a sand bar. It died a few hours later. The carcass was recovered and moved to the Brewster town landfill, where a number of scientists, including Whale Center staff, did a complete necropsy (an animal autopsy) to find out more about why the animal died. The necropsy was led by Katie Touhey of the Cape Cod Stranding Network.
Initially it was not easy to get a look at the fluke pattern of this whale, as it died and was placed belly-down. In order to identify it, we had to have a front-end loader lift the massive flukes (below right) while we lay underneath and looked up. During the necropsy we removed both sides (flukes) of the tail, as you can see in the photo below. We have completed a careful match of this whale against those we have previously photographed, and we have not been able to find a previous history of it.
Based on its size (34 feet), we think that the animal was no more than three years old. The most noticeable thing about the whale, however, was how thin he was. The back by the dorsal fin, where many of the fat reserves are stored, was clearly sunk in, indicating a lack of blubber (see photo below right). Although there were entanglement scars on the base of the flukes, there was no fishing gear on the whale, and no signs a boat had hit it. Instead, he appeared to have died of natural causes.
A very thorough necropsy was conducted on the whale, looking at every internal organ to assess the whale's health. The most noticeable thing we found was a very high number of parasitic worms in the whale's kidney ducts (kidney, below right). Otherwise, although there was a less than ideal fat layer around the whale (see white blubber, below left), the other organs appeared to be in decent shape. There were no food remains in the stomach, but there were fresh feces in the intestines, indicating the whale had been feeding recently.
We suspect this whale may have died of kidney failure. Based on examination of carcasses of fin whales during the whaling period, one scientist had speculated that kidney failure caused by these worm-like parasites was a major cause of death in whales, especially young whales. In the first few years after weaning, youngsters probably have to learn how to find food and feed on that prey. If they are not successful, their body reserves can be depleted, and they can become increasingly susceptible to disease and internal parasites.
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