Sea Otters' Disappearance A Mystery - Reuters

[hatrack]

ANCHORAGE, Alaska - When Russian explorers first saw sea otters bobbing in the waters off Alaska's Aleutian Islands in the mid-18th century, they knew they had discovered a money maker. The otters' fur "is so far superior in length, beauty, blackness and gloss of hair to the river otters' pelts that these can scarcely be compared to it," wrote German naturalist Georg Steller, who accompanied legendary mariner Vitus Bering on his Alaska expeditions.
Russian and American hunters later wiped out nearly all of Alaska's sea otters, whose luxurious fur became known as "soft gold." The otters were saved from extinction after a 1911 treaty banned the commercial hunt.

But sea otters are once again vanishing from Alaska's 1,000-mile Aleutian chain and other parts of southwestern Alaska. This time, there is no obvious explanation.

Alaska's sea otter population numbered 100,000 to 137,000 in the 1980s, with its core in the Aleutians and western Alaska. But numbers fell 70 percent from 1992 to 2000, according to the U.S. Fish and Wildlife Service. Some Aleutian populations are down to just a few thousand, about 5 percent of 1980s' levels, the agency said.

EDIT

Otters eat sea urchins, which feed on kelp. Without the otters to control urchin populations, undersea kelp forests are being mowed down, scientists warn. "Now across the Aleutian archipelago there are these vast areas that are just deforested kelp beds," said Jim Estes, a Santa Cruz, California-based U.S. Geological Survey ecologist and Alaska sea otter expert. That could hurt fish that dwell in kelp beds, Estes said."

EDIT

http://www.planetark.com/dailynewsstory.cfm/newsid/23730/story.htm

[JailForBush]

1. I worked in the Aleutian Islands with the U.S. Fish & Wildlife Service

in the early 1980's. Even then, biologists were warning about all sorts of population crashes. The major problem, of course, was unregulated fishing.

There's one surefire way to rally Republicans to the cause. When Native Americans legally killed a gray whale in Washington State a few years ago, local conservatives and liberals switched sides in one of the most bizarre events I've ever witnessed. Liberals bacame the racists, while Repugs like Senators Slade "Skeletor" Gordon and Jack Metcalf could have passed for Greenpeace officers.

Weird.

[salinen]

2. Jail

That's because sometimes rascism trumps greed.

[xchrom]

3. wasn't there support from japanese and norwegian

whaling industries for that hunt?

[NickB79]

7. Question on overfishing

Are the otters starving from overfishing, or are they getting caught in the nets? If their food source consists a great deal of sea urchins, wouldn't fishing not have much effect on them? Or were sea urchins overfished too (do people even fish for urchins?)?

[blindpig]

4. I think it has something to do with orcas

as I understand it seal populations, which are the basis of the orca diet, have declined for reasons which I'm not clear on. Orcas are eating more sea otters. No documentation.
What have we done now?

[minkyboodle]

8. If I was an Orca

...... well lets say I'd be giving Shamu a bad name. I think it is really interesting that we (humans) aren't on their menu. Orcas are so far on top of the food chain in ocean ecosystems its amazing.
Scott

[yo-yo-ma]

5. as they finally have made a comeback in California n/t

[BrotherBuzz]

6. California sea otter population is having problems, too

California Sea Otter Mystery

<snip>
California sea otters, with their luxuriously soft pelts, were hunted to near extinction by the early 20th century, but have since recovered somewhat, reaching a recent population high of 2,377 off the California coast in 1995.

Since then, however, their numbers have at best stagnated, and at worst decreased, along much of their range, which once extended all along the West Coast, and now is limited to California's central coast. A survey last fall put their numbers at 2,202.

<snip>

Infectious disease seems to be one of the biggest culprits in otter deaths. Disease has always claimed otter lives, but recent research by Miller has shown that a protozoan parasite, Toxoplasma gondii, typically found on land, is more common in water than previously recognized and is finding its way into sea otters.

The parasite causes encephalitis that is killing some otters. More than 60 percent of the dead otters examined are found to have antibodies to this parasite.
<more>

www.cbsnews.com/stories/2003/04/21/tech/main550397.shtml

I think it may be agricultural runoff that is killing them. Like the canary in the mine, The sea otter population is a good barometer on how healthy our environment is. Cute, too!

[Boomer]

9. Multiple pressures

There's probably no one single cause, rather we're reaching the breaking point on the general onslaught on the environment. Over-fishing, water pollution, and global warming are all creating their individual pressures, and then the combination of them all is creating additional chaos and destruction.

From bits and pieces I've read elsewhere, one of the results of global warming is an increase in disease for human population, but probably also by extension to animal populations as well. Cooler temperatures that once limited the range of mosquitos, for instance, are giving way to longer and longer warm periods, and extended geographical areas as well.

So even if researchers determine that an animal species like sea otters is reduced in numbers due to a specific disease, the underlying issue could be global warming. Unfortunately, there's no quick injection to cure that problem.

I'm just glad that at my age I won't make it past 2040 or so. All the grim predictions about deteriorating conditions by the end of this century are probably being overly optimistic. I suspect the crash will come sooner rather than later as the interconnections of our biosphere begin to erode. We keep monitoring the health of individual elements, but systemic failure is rarely a gradual, gentle decline of pieces. It's a sudden crash when the relationship between the pieces erodes beyond a critical level.

--Boomer