EVANSTON, Illinois, January 25, 2011 (ENS) - Extinction cascades are often observed following the loss of a key species within an ecosystem. As the system changes to compensate for the loss, availability of food, territory and other resources to each of the remaining species can fluctuate wildly, creating a boom-or-bust environment that can lead to even more extinctions.
New research at Northwestern University has found that more than 70 percent of these extinctions are preventable, assuming that the ecosystem can be brought into balance and no new factors are introduced.
Northwestern University physics professor Adilson Motter and his student, Sagar Sahasrabudhe, have developed a mathematical model to describe interactions within ecological food webs that could rescue fragile ecosystems and halt complex cascade events.
Published in the January 25 issue of the journal Nature Communications, their study illustrates how human intervention may be effective in species conservation.
"Our study provides a theoretical basis for management efforts that would aim to mitigate extinction cascades in food web networks," Motter said.
The scientists found evidence that some extinctions are caused not by a primary disturbance but as the result of a cascade.
"We find that extinction cascades can often be mitigated by suppressing, rather than enhancing, the populations of specific species," he said.
Motter and his team conclude that large-scale failures can be avoided by focusing on preventing the waves of failure that follow the initial event. …
Wednesday, January 26, 2011
Extinction cascades can be prevented, scientists find
Monday, August 23, 2010
Good riddance to overfishing: New management can end unsustainable practices
Editor's note: This story is part of a series of online exclusives about natural phenomena and human endeavors we'd like to see come to an end. They are connected with the September 2010 special issue of Scientific American called "The End".
The meeting of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES (pronounced "sight-eez") this past March was a decided defeat for the Atlantic bluefin tuna. Delegates voted 72 to 43 not to restrict fishing and international trade of the tuna so prized for its sushi that stocks are estimated to be at 15 percent of their historic levels. Although dismayed, conservationists remain upbeat, because they have at their disposal other management tools that could save the species.
Those strategies belong to the International Commission for the Conservation of Atlantic Tunas (ICCAT), which actually has the job to manage tuna and tunalike species (a point argued by Japan and other opponents of a CITIES trade ban). Conservationists had forged ahead with a CITES effort anyway, because "we felt that a CITES ban would be a useful part of a package of tools to help reduce incentives for going over the quota," says Rebecca Lent, director of the National Oceanic and Atmospheric Administration Office of International Affairs and U.S. commissioner for ICCAT.
ICCAT, one of many regional fishery management organizations around the world, used a different tool to rebuild Atlantic swordfish populations (pdf) last September—namely, quotas. "The most important thing was setting the quotas at the appropriate level," Lent says, so that both the fish and the fishery economy can be sustained. To help enforce those limits, ICCAT tracked international trade to find countries that were catching (and selling) more fish than they reported. And domestically, the U.S. prohibited fisheries from waters where juvenile swordfish were getting killed as bycatch.
Still, getting countries to adhere to quotas is "the hardest challenge internationally," Lent says. Catch share programs, in which regional fishery councils divvy up quota shares to fishermen, could help ease this burden. Instead of creating a "struggle over a shrinking pie, you make [fishermen into] stakeholders, and that generates an incentive to be better stewards," says Frank Alcock, director of the Marine Policy Institute at the Mote Marine Laboratory in Sarasota, Fla. In the Pacific Northwest, for example, the program helped cut halibut fishing levels by one quarter. …
Good Riddance to Overfishing: New Management Can End Unsustainable Practices
Saturday, March 20, 2010
Closing of sushi restaurant that served endangered whale ‘a self-imposed punishment’
I’ve never seen anything like this announcement from a business:
After twelve years doing business in Santa Monica, The Hump will be closing its doors effective March 20th, 2010.
The Hump hopes that by closing its doors, it will help bring awareness to the detrimental effect that illegal whaling has on the preservation of our ocean ecosystems and species. Closing the restaurant is a self-imposed punishment on top of the fine that will be meted out by the court. The Owner of The Hump also will be taking additional action to save endangered species.
One such action will be to make a substantial contribution to one or more responsible organizations dedicated to the preservation of whales and other endangered species.
The Hump apologizes to our loyal customers, the community of Santa Monica, and the public at large for our illegal actions. While the current difficulties faced by The Hump overshadow the many friendships formed over the years, we want our customers and friends to know how much we thank you for your support.
Thursday, March 11, 2010
Sushi chef, restaurant charged with serving endangered whale
(Reuters) - A California sushi chef and the restaurant in which he worked have been charged with illegally serving meat from an endangered Sei whale, the Justice Department said on Thursday.
Kiyoshiro Yamamoto, 45, and the parent company of the popular restaurant The Hump in Santa Monica were charged late on Wednesday with violating the Marine Mammal Protection Act which makes it illegal to sell any kind of whale meat.
The case stemmed from informants who ordered whale meat at the restaurant in October 2009 and evolved into a sting operation by U.S. wildlife and customs officials who observed whale meat being served at the restaurant last week.
"Someone should not be able to walk into a restaurant and order a plate of an endangered species," U.S. Attorney Andre Birotte Jr. said in a statement. …
Sushi chef, restaurant charged with serving endangered whale
Thursday, October 15, 2009
Trade curbs sought for sharks, corals, bluefin tuna
By Laura MacInnis
GENEVA (Reuters) - Tuna popular in sushi, colorful corals used in jewelry and sharks whose fins make soup have been proposed for international trade restrictions overseen by the United Nations, a spokesman for the treaty said on Thursday.
Juan-Carlos Vasquez of the Convention on International Trade in Endangered Species (CITES) said countries had submitted 40 requests for trade curbs and controls that will be reviewed at a conference in Qatar in March.
African elephants, some plants from Madagascar, the skins of certain snakes and crocodiles, and a range of waxes and oils used in cosmetics were also suggested for the regulation which aims to encourage conservation, Vasquez said.
"We check that the trade is sustainable, is legal and is traceable," he explained. CITES registration gives protection to endangered species carrying high economic or commercial value.
Most of the plants and animals proposed for the 2010 Doha conference would, if approved by CITES' 175 member states, be regulated in a government permit system certifying their trade.
But Monaco proposed that Atlantic bluefin tuna be subjected to a full ban, which could cause big losses for Mediterranean countries who have resisted European Union calls to stop fishing the over-exploited population. …
Trade curbs sought for sharks, corals, bluefin tuna
Thursday, October 8, 2009
Feds give sea otters habitat protection in Alaska
By MARY PEMBERTON , Associated Press Writer
(AP) -- Four years after being placed on the Endangered Species List, the dwindling sea otters of southwest Alaska on Wednesday were given an important recovery tool.
The U.S. Fish and Wildlife Service designated nearly 5,900 square miles as critical habitat for sea otters in the Aleutian Islands, Bering Sea and Alaska Peninsula. The designated area includes all nearshore waters.
"Critical habitat has a proven record of aiding the recovery of endangered species," said Rebecca Noblin, a lawyer for the Center for Biological Diversity, which filed two lawsuits and engaged in years of litigation to get the animals protected under the federal Endangered Species Act. The otters in southwest Alaska were listed as threatened in 2005.
"This has been a long time coming," she said.
Critical habitat gives the sea otters - the smallest of marine mammals - a "fighting chance of recovery," she said.
Nearshore areas were chosen because most of the creatures that sea otters eat - sea urchins, crabs, octopuses and some bottom fish - are found in shallow waters. Areas close to shore also provide the best protection from marine predators, especially killer whales, according to the Fish and Wildlife Service.
Federal law requires that critical habitat be designated at the time of listing. But when that didn't happen under the Bush administration, the Center for Biological Diversity filed a federal lawsuit in 2006. The following year an agreement was reached that critical habitat would be designated by this October. …
Feds give sea otters habitat protection in Alaska
Tuesday, September 15, 2009
Sushi lovers tense in Tokyo as bluefin tuna nears endangered listing
By Peter J Brown
A few European countries are taking steps to save the world's bluefin tuna population. This month, the European Commission (EC) announced its support for a formal listing of the species as endangered under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which would in effect ban any international trade in bluefin tuna.
Japan is the world's biggest importer of bluefin tuna, which can weigh as much as 300 kilograms or more. Considered a highly prized delicacy by the Japanese, the fish are often sold to customers in wafer-thin slices at sushi bars and restaurants. Whereas a fishing boat owner or captain might sell the fish to a buyer at the dock for $30 to $40 per kilo, that price could increase tenfold or more by the time it lands on someone's plate in Japan.
Prices tripled from 2007 to 2008. One bluefin tuna caught in Japanese waters sold at auction in Japan this year for over $100,000, well short of the all-time record which was set in 2001 at over $150,000.
According to the Asahi Shimbun, Japan consumed 43,000 tons of bluefin tuna last year, and "a total ban on trade of Atlantic and Mediterranean bluefin tunas would translate to a cut of about 20,000 tons". …
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