Spate of Blue whale deaths off California24/06/2006 00:00:00
September, 2007. To the alarm of marine scientists, three blue whales have been found dead off the coast of Southern California in the past two weeks. As many as 200 blue whales have been feeding in the Santa Barbara Channel during their annual summer migration from Mexico and Central America. About 3,000 of the world's 12,000 blue whales live off the west coast of the Americas. The latest dead whale was spotted Wednesday floating in the Santa Barbara Channel, and there are plans to bring the carcass ashore. The dead whale is believed to be a 70 foot long male whale, weighing more than 50 tons.
Two more dead Blue whales
Last week, a dead blue whale beached about 10 miles up the coast from Ventura and another was found in Long Beach Harbour before being towed out to sea. There have been only 6 reported Blue whale strandings since 1980, so to have three in two weeks is a very worrying sign, and has puzzled marine scientists.
These two whales, found with many of their bones broken, are believed to have been struck by ships in the busy shipping channel. It is not known yet if this latest whale suffered a similar fate.
Frances Gulland, director of veterinary science at the Marine Mammal Centre in Sausilito, California and other biologists plan to examine the latest dead whale to determine if it may have been disoriented by some sort of illness.
Dr. Gulland says the appearance of these three whale carcasses is ‘a highly unusual event and may be an indicator of an unusual mortality event.’ She was one of the scientists who determined that the whale found north of Ventura had been hit by a ship.
That whale was a female sub-adult to adult about 72 feet long according to the Santa Barbara Museum of Natural History. The whale was about three to five years old. She was not pregnant and was most likely not of breeding age.
A necropsy conducted by that Marine Mammal Stranding Network, the Santa Barbara Museum of Natural History, the Marine Mammal Center and the Channel Islands Marine and Wildlife Institute revealed that the most likely cause of death was a ship strike along the back side of the whale. Date, time, and exact location of the incident and death are unknown.
Scientists were able to collect tissue samples which were taken for biochemical and genetic testing. The results will be available in about a month.
The skull and some of the broken vertebrae were harvested by the Santa Barbara Museum of Natural History. The museum had hoped to collect the whole skeleton, but the bones were too badly damaged.
Paul Collins, curator of vertebrate zoology at the museum, says it is normal for large sized ships and tankers to be in the Santa Barbara Channel, as it is normal for blue whales to be in the channel. This particular summer, there seems to be greater numbers of blue whales in the channel, possibly due to richer food sources.