Caspian Seal is Now an Endangered Species
Marine Mammal Population Collapse is the Result of Many Factors
Dec 18, 2008
The Caspian seal (Phoca caspica) inhabits a landlocked sea, surrounded by five countries-Iran, Kazakhstan, Turkmenistan, Russia and Azerbaijan. Based on recent survey work, the International Union for the Conservation of Nature (IUCN) has moved the species from Vulnerable to Endangered status.
Survey Results Show Massive Caspian Seal Population Drop
Over the last 100 years the numbers of Caspian seals have dropped by 90 percent. More critically, surveys over the last few years show that the population of these seals has fallen precipitously since 2005. The numbers of Caspian seal pups being born is down to 6,000 or 7,000, a nearly 60 percent decline between 2005 and 2008. And there are one-third fewer adults being seen on the breeding grounds. Marine mammals are long-lived, slow reproducing species, which means that such a steep decline may not be reversible.
Commercial Hunting an Important Factor in Caspian Seal Declines
In past years commercial hunters from the Russian Federation killed more than 8,000 Caspian seal pups, which has meant there are far fewer animals surviving to breeding age. In 2006, only 17,000 females were of reproductive age. Pup survival, even with no human impact is generally less than 50 percent, so further losses to hunting are no longer sustainable.
Fishing and Pollution Take a Toll on Caspian Seal Populations
Each year Caspian seals die from entanglement in fishing nets. In 2007 over one hundred seal carcasses washed ashore in Kazakhstan, prompting an investigation into the cause. Canine distemper virus was originally suspected as there had been an outbreak of the disease in 2000. This disease was ruled out by virology tests. Scientists now feel the seals may have died in sturgeon fishing nets as fishermen have acknowledged that hundreds may be trapped at one time.
The enclosed nature of the Caspian Sea means that there is minimal water exchange. Pollutants discharged into the Caspian remain there. Industry along the coasts not only pollutes the waters, it reduces the number of places where the Caspian seal can haul out to rest. The time spent on land is important for seals to conserve energy, rest and warming themselves.
The Caspian Seal Recovery Plan
While the recovery plan for this unique seal has not been accepted in full by all countries along the waters of the Caspian Sea, there is some movement in the right direction. Kazakhstan’s government has acknowledged the need for quick action. Two important steps will be to start with a ban on commercial hunting and to provide protected areas where the animals are undisturbed. Other efforts will concentrate on pollution remediation, changes to fisheries to reduce deadly interactions and ensure a food supply for the seals.
The Caspian seal joins many other marine mammals, including both species of monk seal and the Ganges River Dolphin, in facing possible extinction. The Darwin Caspian Seal Project, a cooperative effort by seal specialists initiated in 2006, is working to ensure that doesn't happen.
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