Environmental News Archive

An almost weekly update of environmental news, particularly marine updates, with occasional splatters of transportation, indigenous, ideas of sustainability and sustainable development from around the world.


News Review for Week August 15 - August 21, 2005

News Review for Week August 15 - August 21, 2005
Compiled by November Tan, Intern
Edited by Holly S. Lohuis
Ocean Futures Society

Man spies bull shark under board
August 19, 2005 (BBC)
A surfer has said he spotted one of the world's most dangerous sharks in the sea off west Cornwall.
Luke Goodman, 25, from Penzance, said a bull shark at least 6ft (1.8m) long swam under his surfboard while he was in the water near Sennen Cove.
Bull sharks are from the same family as the reef shark. They can be up to 11.5ft (3.5m) in length and are known for their attacks against bathers.
But experts have said they have never been seen in European waters before.
Basking sharks are a common sight around Cornish waters in the summer, but they are plankton-eating fish, not human predators.

Ocean bug has 'smallest genome'
August 19, 2005 (BBC - By Roland Pease)
Small but perfectly formed, Pelagibacter ubique is a lean machine stripped down to the bare essentials for life.
Humans have around 30,000 genes that determine everything from our eye colour to our sex but Pelagibacter has just 1,354, US biologists report in the journal Science.
What is more, Pelagibacter has none of the genetic clutter that most genomes have accumulated over time.
There are no duplicate gene copies, no viral genes, and no junk DNA.
The spareness of its genome is related to its frugal lifestyle. The shorter the length of DNA that needs to be copied each generation, the less work there is to do.
Pelagibacter has even gone one step further. It has chosen where possible to use genetic letters - or base pairs - which use less nitrogen in their construction: nitrogen is a difficult nutrient for living things to obtain.
The result is one of the most successful organisms on the planet. Pelagibacter feeds off dead organic matter that is dissolved in ocean water - lead researcher Stephen Giovannoni of Oregon State University likens it to a very thin chicken soup.

Waves of hope in power research
August 19, 2005 (BBC)
Researchers studying waves 12 miles (19km) off the north Cornish coast say they have new evidence proving the area has huge potential to make electricity.
The height of the waves and the strength of the currents have been measured at a fixed location over three months using a special buoy.
The average wave height was about 2m (6.6ft), and the largest wave recorded in February was nearly 9m (29.5ft).
A Wave Hub to harness the waves is due to be put in place in the area in 2007.
BBC South West Environment Correspondent Adrian Campbell said: "The data is good news for the producers of wave to energy converters, which would look like giant snakes sitting on top of the water.
"They would eventually be linked up to a device to be installed on the sea bed called a Wave Hub. That is due to be put in place by 2007.

Coral Reef Ecosystems Found To Be in Decline in U.S. Waters
August 19, 2005 (AP — By John Heilprin)
WASHINGTON — Coral reef ecosystems, among the oldest and most diverse forms of life, are declining in U.S. waters because of overfishing, climate change, marine diseases, land-based pollution, storms and grounded ships.
Such ecosystems "clearly are beset by a wide array of significant threats," the National Oceanic and Atmospheric Administration said in a report Thursday.
About three-quarters of all the threats to coral reefs have not changed since the agency's last overview three years ago. Nearly half of those are considered medium to high threats.
Only in one place, Guam, did a threat level go from low to high, because of coral bleaching from rising ocean temperatures.
Coral reefs provide food and shelter to fish and protect shores from erosion.
The 522-page report says many of the programs that scientists use to monitor coral reefs only began in the past two to five years, so some of the data is inconclusive.
But the agency's head, Conrad Lautenbacher, said the findings offer "a baseline we can use to compare future results."
The data comes from more than 160 scientists and coral reef managers who have monitored the water quality, the sea floor and fish and other species that live in coral. They also have expanded their digital mapping of shallow water coral reef ecosystems.
Globally, only about 30 percent of the world's coral reefs are healthy, according to a study last year by 240 scientists in 96 countries. That is down from 41 percent in 2002.
That report listed global warming -- blamed for higher water temperatures and carbon dioxide concentrations -- as the top threat. It found that the Caribbean had lost 80 to 98 percent of its elkhorn and staghorn coral, which are both among the most common species.

Sexy Posters to Protect Mexico's Turtles
August 19, 2005 (Reuters)
MEXICO CITY — Sex sells everything from diet products to car tires, but Mexican authorities have found a new use for posters of scantily dressed young women: protecting endangered sea turtles.
An advertisement campaign featuring an Argentine model casting a sexy gaze is to be launched in September in the southern state of Guerrero to dispel myths that sea turtle eggs are an aphrodisiac, environmentalists said Thursday.
"My man doesn't need turtle eggs. Because he knows they don't make him more potent," reads the poster, aimed at stopping poachers from stealing eggs.
Every year, tens of thousands of turtles come ashore to lay their eggs on Mexico's Pacific and Caribbean beaches. Many fall prey to poachers who kill the females, extract the eggs from their wombs and sell them as a supposed aphrodisiac.
But the posters have outraged a government body defending women's rights, which says using images of women to raise consciousness is degrading, even if it is for a good cause.
Earlier this month, poachers bludgeoned and chopped to death some 80 protected Olive Ridley sea turtles for their eggs and left their shells scattered on a Pacific beach in Mexico.

Fishing, Climate Change, Development Jeopardize U.S. Coral Reefs
August 19, 2005 (ENS)
WASHINGTON, DC - Coral reef ecosystems of the United States and associated Pacific Islands are still under pressure from overfishing, disease, pollution, coastal development, and climate change finds a new national assessment of the condition of U.S. shallow coral reef ecosystems.
The report, was authored by teams in 14 jurisdictions where the corals are found and was released Thursday by the National Oceanic and Atmospheric Administration (NOAA).
It marks the first attempt to bring together quantitative results of monitoring data and information collected by federal, state, territory, commonwealth, nongovernmental, private and academic partners to provide an overall status report on the condition of U.S. coral reef ecosystems.
Of particular concern was the impact of fishing on coral reef ecosystems. Experts in eight of the jurisdictions perceived fishing as a high threat to coral reef ecosystems, while the rest viewed it as a medium threat.
Adverse impacts of fishing include changes in the populations of marine organisms, and fish in particular, that "can have far-reaching cascade effects throughout the ecosystem," the report warns.

'Unique' sighting of fin whales
August 18, 2005 (BBC)
Just days after the sighting of around 2,000 dolphins off the west Wales coast, a school of giant fin whales has been spotted fishing in the Irish sea.
The sighting by an Oxford University team was described as "unique" as they are normally on their own or in pairs.
Zoologist Dr Peter Evans said the sea "teeming with food" has put west Wales on the whale watching map.
"It was an experience of a lifetime. I see whales all around the world but this was really spectacular."
Steve Lewis whose safari company ran the trip, added: "These huge animals are normally seen singularly or in pairs.
"This is the biggest sighting of fin whales ever spotted in UK waters.
"The boat we were in was 35 feet long, and the biggest of the whales was bigger than that. It must have been 40ft plus.

Commission Votes to Cap Annual Catch of Menhaden Fish in Chesapeake
August 18, 2005 (AP — By Matthew Barakat)
ALEXANDRIA, Va. — Concerned about potential overharvesting, a regional commission has voted to limit the catch of a small but ecologically important fish in the Chesapeake Bay.
Wednesday's vote by the Atlantic States Marine Fisheries Commission would curtail the annual menhaden catch in the bay to 106,000 metric tons for five years beginning in 2006. The Virginia General Assembly must now enact new laws to implement the mandate.Texas-based Omega Protein is the only significant fisher of menhaden in the Chesapeake, but it's unclear whether the cap would be effective. Company spokesman Toby Gascon said that some years it catches more than the cap amount and others less.
Gascon said after the hearing Wednesday that the commission has "abandoned" the fishing industry. Virginia's representatives on the commission also opposed the cap and raised the possibility that the state could defy the new regulations.
Omega has more than 250 workers at its Reedville plant, making it the largest private employer in rural Northumberland County.

Marine survey could boost tourism
August 17, 2005 (BBC)
The tourist industry could be boosted by a new marine survey off Devon and Cornwall, scientists say.
The Marine Conservation Society (MCS) is to count the number of turtles, basking sharks, dolphins, porpoises and jellyfish blooms off the coast.
It will then pass the information to people running sea safaris for tourists to help them find the creatures.
The three-year survey will cover the sea up to 12 miles off the region's coastline.
The MCS said it hoped the more tourists who see the animals in their natural environment, the more interest there will be in preserving them.
The society is looking for a pilot and an aeroplane to help with the survey.
Two years ago Orca Sea-Faris based in Falmouth received a cash investment by Finance Cornwall and the Cornwall Business Enterprise Fund to operate educational whale and dolphin spotting trips.

Pacific Coast Ecosystems Return to Normal after Winds Arrive Late
August 17, 2005 (AP — By Terence Chea)
SAN FRANCISCO — The northerly winds that sustain the Pacific Coast's marine ecosystems have returned, but their arrival came too late for fish and birds that couldn't survive the unseasonably warm waters.
William Peterson, an oceanographer with the National Oceanic and Atmospheric Administration in Newport, Oregon, who just returned from a 10-day trip Sunday, said ocean conditions have returned to normal off the coasts of California and Oregon, but it's too late for many species.
"The water is very cold and productive. It's the way we would expect it to be," Peterson said. "But the animals that depend upon the ocean being productive in the spring and the early summer are dead. It's not going to help them any."
Coastal ecosystems rely on winds blowing south to push warmer surface waters away from shore and bring up colder, nutrient-rich water from the ocean bottom that feeds massive blooms of plankton -- the tiny plant-like organisms that form the basis of the marine food web.
The winds usually start blowing in March or April, but when they didn't arrive this spring, researchers saw the effects up and down the coast -- higher ocean temperatures near the shore, very little plankton, a drop in groundfish catches and a spike in dead seabirds on beaches.
The winds finally returned in mid-July and generated the long-delayed upwelling and a dramatic increase in plankton populations, according to researchers.

Red Tide Bloom Strikes Off Florida Coast
August 17, 2005 (AP)
TAMPA, Fla. — An unusually fierce red tide bloom this summer has choked off oxygen and killed undersea life in a region of the Gulf of Mexico bottom about 10 miles off the coast of Florida, scientists said.
Red tide is formed when a microscopic algae reproduces at an explosive rate. The algae produces a neurotoxin that can paralyze or make breathing difficult for fish, manatees or even humans that inhale or ingest it.
During a three-day expedition last week, researchers from the state's Fish and Wildlife Research Institute and the University of South Florida sampled 28 spots from the mouth of Tampa Bay north to Pasco County, on the north side of the Tampa metropolitan area, and from along the shore out to 30 miles offshore. Preliminary results of the research were reported Monday.
However, some spots where divers had reported no life during earlier investigations are starting to see fish return, institute spokesman Jeremy Lake said.
"Some of them are starting to heal," he said.

Full Moon in August: Time for Coral to Spawn - Researchers Have Once-a-Year Chance to Observe, Study Coral Spawning
August 17, 2005 ( University of Miami Rosenstiel School)
VIRGINIA KEY, Fla. — In the Florida Keys, the August full moon represents a unique and precious event: annual coral spawning for some of the most threatened corals in the world.
This year, like many others, researchers from the University of Miami Rosenstiel School and University of North Carolina Wilmington will spend the latter part of August and early September studying the phenomenon in the Florida Keys National Marine Sanctuary to understand how humans can improve the plight of elkhorn, staghorn, boulder star and other species of corals.
“We’ve been at this for quite a while, and each year we learn a little bit more about these corals,” said Margaret Miller, adjunct assistant professor in Rosenstiel School’s Marine Biology and Fisheries Division and benthic ecologist with the National Oceanic and Atmospheric Administration (NOAA)-Fisheries, Southeast Fisheries Science Center. “Unfortunately, we only have one opportunity a year to observe these corals spawning.”
Alina Szmant, who is now a professor at the University of North Carolina Wilmington’s Department of Biology and Marine Biology and Center for Marine Science, began this work back in 1983 when she was a faculty member at Rosenstiel School. Since then, the researchers have learned to predict the narrow time frame during which these corals will be spawning. For this group of species, this is during the late evening hours over the week or so after the full moon in August.

Spanish Surfers' Paradise Loses its Wave
August 17, 2005 (REUTERS)
MUNDAKA, SPAIN - U.S. surfer Mike Dobos emigrated to this tiny Basque village just to ride its wave. Eight years later, one of the most famous waves in the world has disappeared.
Thousands of surfing enthusiasts used to descend on this northern Spanish village every year for surfing's premier competition, the World Championship Tour.
This year, the Mundaka leg of the Billabong Pro championship has been cancelled because the wave, known as the best "left-hand" in Europe, has vanished.
"I'm shattered," 37-year-old Dobos said. "I left everything behind exactly to do this, to surf this wave."
Where once a powerful wave created by a sand bar curled into a long fast-moving tube, the sea is now calm like the Mediterranean. Instead of surfers, sailing boats and canoes dot the clear blue water.
Foreign surfers stumbled on Mundaka, an ancient village with strong Basque nationalist feeling, in the 1960s. The locals soon realised what could be done with their barrel-shaped wave and bought boards from the visitors.
Bruce Smith, from Perth, Australia, was one of the first to make surfboards here, arriving in 1982.
"Getting a tube is the most exciting part of surfing. Here you get very deep, intense tubes," he said.
Smith and other surfers are convinced the wave disappeared because the estuary was dredged in 2003 to make way for a newly built ship. The sand was used to restore a huge dune nearby and provide a home for endangered plants, and birds such as plovers.
Local officials have ordered a study into what happened to Mundaka's wave. Some scientists say it is just not clear why the vast tubes that drew surfers from around the world no longer roll across the bay.

Off the Cape, the Cod Continue to Dwindle
August 17, 2005 (Washington Post - By Juliet Eilperin)
Cape Cod's population of its namesake fish dipped by 25 percent between 2001 and 2004, according to preliminary findings by federal scientists, indicating that the once-abundant cod has yet to rebound despite years of government protection.
A group of scientists from the National Oceanic and Atmospheric Administration's Fisheries Service and the New England Fishery Management Council reported Monday at a public workshop that fishermen continue to take too many adult cod and that not enough juvenile fish are surviving to replenish the population's ranks.
Andrew A. Rosenberg, a professor of natural resources policy and management at the University of New Hampshire who oversaw New England groundfish stocks under President Bill Clinton, said the new numbers show the government needs to impose further restrictions on fishing cod.
"They're still fishing them, and when you kill them, they tend to die," Rosenberg said.
But Pat Fiorelli, a spokeswoman for the New England Fishery Management Council, said officials did not expect the government's new rebuilding plan to show results for several more months. The average New England fisherman can take groundfish only 53 days a year now, she added, down from 88 days in 1996.

Rare fish settle in new lake home
August 16, 2005 (BBC)
A radical project to relocate 70,000 fish eggs in an effort to save a rare breed has proved successful.
The eggs, from endangered vendace, were taken from Bassenthwaite Lake, Cumbria, to Loch Skene, in Dumfriesshire.
The move followed fears that poor water quality and pollution in Bassenthwaite could wipe out the whitefish, which can be traced back to the Ice Age.
The fish are now doing well in their new Scottish home and a second Lake District lift is planned this winter.
Historically, vendace were recorded at four UK locations - Bassenthwaite, Derwentwater, Castle Loch and Mill Loch in Dumfries and Galloway.
The Castle Loch population disappeared at the beginning of the 20th Century and Mill Loch shortly before the end.

Scientists Track Alien Seaweed in Hawaii
August 16, 2005 (AP — By Jaymes Song)
HONOLULU — An alien seaweed introduced here 31 years ago has spread rapidly throughout Hawaii and has even reached the remote, unspoiled Northwestern Hawaiian Islands, which has scientists worried.
Researchers on the National Oceanic and Atmospheric Administration's research ship Hiialakai were scheduled to leave Friday in the first major effort to gauge the spread of Hypnea musciformis. The study is part of a mission of the 10-day cruise through the protected waters to educate science teachers about the marine environment.
"If there is a lot, then we're going to have to do something drastic like mount a campaign to go up there and haul it out of the ocean," said Isabella Abbott, an award-winning botanist at the University of Hawaii and the state's top seaweed expert.
The seaweed, also known as hookweed and commonly found in the Caribbean, was introduced to Hawaii in 1974 from Florida for aquaculture purposes. But after a failed attempt to cultivate it for a commercially valuable ingredient, the algae was abandoned in Kaneohe Bay.
It has since spread to every major Hawaiian island except Kahoolawe and the Big Island, plaguing beaches, choking reefs and overtaking native algae. It is not known why those two islands have been untouched.

New York Scientists Track Humpback in Two Ocean Basins
August 16, 2005 (ENS)
NEW YORK, New York - For the first time ever, a genetic study has followed a single humpback whale from one ocean basin to another, adding to traditional notions of the migratory patterns of these majestic marine mammals in the process, according to researchers from the Wildlife Conservation Society (WCS), the American Museum of Natural History (AMNH), and New York University.
In a study published in the current issue of the Royal Society's "Biology Letters," a male humpback whale that was first sighted in Madagascar's Antongil Bay in 2000 was found in 2002 swimming off the coast of Loango National Park in Gabon - on the other side of the African continent.
"While the movement of whales from one ocean to another has always been a possibility, it's quite difficult to track in the wild," said WCS researcher Dr. Cristina Pomilla, lead author of the study. "This study demonstrates the ability of molecular technologies to confirm the movements of an individual whale between ocean basins."
The study examined DNA samples extracted from skin biopsies collected from whales in the wintering grounds of both the Indian and South Atlantic Oceans for evidence of inter-oceanic exchange of individuals.
Using a method of genetic capture-recapture of genotypes constructed of microsatellite markers, the researchers identified an individual whale sampled in Gabonese waters in 2002 that had been first seen and sampled with its mother in Madagascar waters in 2000.

Irradiation of Oysters, Mussels, Clams Approved
August 16, 2005 (ENS)
WASHINGTON, DC - When it comes to announcing new regulations that allow ionizing radiation to be used on food, the U.S. government always calls the process "safe."
Today The Food and Drug Administration (FDA) announced that it is amending the food additive regulations "to provide for the safe use of ionizing radiation for control of Vibrio species and other foodborne pathogens in fresh or frozen molluscan shellfish" such as oysters, mussels, clams.
But Wenonah Hauter, director of the Food Program for the campaign group Public Citizen, is not so sure.
Calling the FDA's decision to permit the use of irradiation on oysters, clams and mussels "misguided," Hauter says despite years of consumer resistance to eating irradiated food, "the government continues to forge a path down which very few consumers are willing to tread."
"Grocery stores rarely carry irradiated meat because it doesn't sell. The National School Lunch Program has yet to order a single pound of irradiated ground beef despite the federal government's 2003 approval of such purchases for the program," said Hauter. "Several food irradiation facilities have closed their doors in the past two years due to lack of business."
The FDA is promoting irradiation despite the fact that questions about long-term health impacts of irradiation remain unanswered and despite the fact that alternatives exist, she said.

Jellyfish invade the globe, thanks to humans
Watery creatures carried by ships across the world
August 16, 2005 (LiveScience - By Robert Roy Britt)
There are exotic Frankenfish in the Potomac, unbearably noisy foreign frogs in Hawaii, and the destructive spiny water fleas that have snuck into northern lakes.
Now you can add alien moon jellyfish to the growing list of invasive species that threaten ecosystems around the planet.
Scientists announced the discovery of 16 new species of "moon jellyfish" today while also saying the creatures are invading marine environments all over the world.
The jellyfish are carried by ships, the researchers said. They join several other species that have hitchhiked into new habitats, often to the demise of native species.
The moon jellyfish could not have migrated naturally to so many corners of the globe, the scientists report.
The researchers conducted a 7,000-year computer simulation of possible movement based on ocean currents and the creatures' less-than-Olympic swimming skills. That combined with genetic data leaves ships as the only logical mode of transportation.
Ships take in water for stability, and some ends up in faraway harbors.

Dolphin spectacle baffles experts
August 15, 2005 (BBC)
A group of up to 2,000 common dolphins has been spotted off the coast of west Wales.
Marine experts said it was "massively unusual" to see so many off the Pembrokeshire coast, and the reason remained a mystery.
Cliff Benson, who runs Sea Trust, the marine branch of the Wildlife Trust of South and West Wales, said it had been an incredible sight.
"It's fairly normal to see a hundred or so, but not thousands."
Mr Benson, who carries out regular survey work on cetaceans - dolphins, whales, and porpoises - was on his boat when he saw the dolphins approaching.
"It was like a volcanic eruption," he said. "There were dolphins of all ages - adults and mothers with their babies - and they were leaping out of the water.
It's a mystery as to why there were so many. It could be because the waters are so rich in food, and that there aren't many predators.
"They could be coming here specifically to breed because the conditions are so right."

China to Build Offshore Wind Power Complex
August 15, 2005 (AP)
SHANGHAI, China — China plans to construct its first offshore wind power complex next year in hopes of easing chronic electricity shortages, the official Xinhua News Agency reported Monday.
The complex, to be built in the Bohai Sea off the northern province of Hebei, is designed to have a generating capacity of 1 million kilowatts when completed in 2020, Xinhua said.
An initial phase to begin construction late next year will generate 50,000 kilowatts, it said, citing Gao Xihai, a vice manager of the Huanghua Port Development Zone which is promoting the project.
The plans come as Chinese cities struggle with power shortages that have forced scheduled blackouts and required industries to close or shift production to weekends or other times when demand is weakest.
Officials announced last week that China plans to add 70 million kilowatts annually to the power grid through 2007 for a total of 650 million kilowatts. They said China could by then have an electricity surplus.
China is heavily reliant on coal burning thermal power plants, but reportedly has set a generating target of 20 million kilowatts from renewable energy sources such as hydropower, solar power and wind power by 2020.
China's government says wind power potentially could generate 253 million kilowatts, although only a tiny fraction of that has so far been exploited.

Angling 101: College Offers Class in How To Catch Alaska Fish
August 15, 2005 (AP — By Dan Joling)
COOPER LANDING, Alaska — Curt Muse stood on the cobbled shore of a creek, casting a 3-weight fly rod upstream as a dozen students -- all middle-aged or older -- watched.
Muse was the day's guest lecturer for the Kenai Fishing Academy, a weeklong class offered four times a summer by Kenai Peninsula College, a branch of the University of Alaska Anchorage.
As the students looked on, the longtime guide spotted a sockeye salmon, red as a fire hydrant but easy to miss swimming above colored rocks and below the rippled surface.
"You can barely see that fish and he's red," Muse observed.
Now in its third year, the noncredit course is aimed at fishing novices or anglers new to Alaska who want to avoid learning by reading how-to books or trolling for tips from salesmen at sporting goods stores.
The academy was the brainchild of Gary Turner, the college's director and an avid fisherman who helps teach classes.
"I thought, we need to educate people and teach them how to fish," Turner said. "It just seemed natural."

Estuary Protection Wins Public Support
August 15, 2005 (Coastal Cooperative Research Centre)
BRISBANE, AUSTRALIA — Australia's love affair with the coast has finally embraced estuaries, largely due to a multi-disciplinary team of scientists and natural resource managers collaborating since 2000.
Many of the nation’s estuaries — areas where fresh water from rivers mixes with salt water — have suffered years of human impact and planning neglect. Urban sprawl and the ‘sea-change’ trend to live near bays, beaches, river mouths and wetlands have put significant pressure on coastal waterways and catchments.
Thanks to a national coastal research and development program, the tide has turned. The Coastal Cooperative Research Centre (Coastal CRC) has bridged the gaps between estuary science, planning and policy by federal, State and local governments, and community groups.
The Coastal CRC’s National Estuaries Package assessed the condition of Australia’s 970 estuaries, designed models and indicators to measure changes to estuary health and put practical management and monitoring tools into the hands of local councils and community groups in areas around Australia.
The package, a finalist in the 2004 and 2005 Eureka Science Awards, includes an economic valuation of estuaries. Studies by Professor Robert Costanza of the University of Maryland in the United States reveal that each hectare of an estuary is worth approximately AUD$41,000 per year in its capacity to manage sediment, recycle nutrients, treat waste matter and provide food, transport and recreation to the local community. Australian scientists believe the true value is even higher.

Polar Bear Makes Huge 74 Km One-Day Arctic Swim
August 15, 2005 (REUTER)
OSLO, NORWAY - Scientists have tracked a tagged polar bear swimming at least 74 km in just one day -- and maybe up to 100 km -- providing the first conclusive proof the bears can cover such giant distances in the water.
Bears often roam thousands of kilometres in a year in search of prey such as seals and there has often been anecdotal evidence of prodigious ursine swims, with bears turning up on remote islands or across wide bays.
However, previously there had been doubts about whether the bears had walked over ice part of the way or hitched a ride on an iceberg.
"What's new this time is that we have data showing how long the bear was in the water," Jon Aars, a researcher at the Norwegian Polar Institute, said on Friday.
"This is the first time that such a long swim has been documented by satellite telemetry for polar bears," the institute added.
The female bear, equipped with a satellite tracking device, entered the water on the east of the Norwegian Arctic island of Spitsbergen early on July 20, swam northeast and re-emerged on the island of Edgeoya a day later.
A sensor on the bear's collar sent different signals when it was in salty sea water compared to on land or on ice.
"This is an astonishing swim," Aars said, saying it showed that polar bears could in many ways be classified as marine mammals -- a group including whales and dolphins.
Aars said the bear, dubbed "Skadi" after a Norse goddess of snow, had probably swum closer to 100 km (62 miles) since the bear almost certainly did not swim the 74 km (46 miles) between the two points in an exact straight line.
The bear covered the gap in about 24 hours, giving an average speed of 3-4 kmh -- about as fast as a person walking.

Children pledge to help rare fish
August 9, 2005 (BBC)
Youngsters are being asked to help secure the future of an endangered species of fish.
Bassenthwaite is one of only two lakes to be populated by vendace, a rare fish dating back to the Ice Age.
The Lake District Visitor Centre in Brockhole has created an exhibition to highlight the plight of the vendace.
It appeals to junior environmentalists to use less shampoo and soap to avoid polluting the lake, and to encourage family and friends to use less water.
A giant vendace called Vinny, made from papier-mache and covered in scaly bubble-wrap, explains how small things can make a big difference to wildlife.
Children are encouraged to post up their own promises, such as to turn off the tap while cleaning teeth, or walk on footpaths to avoid loosening soil which can get washed away by rain and end up in lakes and rivers.
John Pinder, manager of the Bassenthwaite Lake Restoration Programme, said: "It's great to get this sort of response. Obviously children love the display and are keen to do their bit.
"It's important they understand from an early age that small actions can make a big difference to lakes like Bassenthwaite."