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President Bush will establish three national monuments in the Pacific Ocean today in a move that will protect a vast marine ecosystem from mining, oil exploration, and commercial fishing. With the stroke of a pen this afternoon, Bush will have set aside more square miles of ocean for protection than any other political leader in history. The three new monuments, surrounding far-flung islands, reefs and atolls scattered across the Pacific, will add 195,000 square miles of protected waters to the nearly 140,000 square miles around the Northwest Hawaiian Islands that Bush protected in 2006 [Los Angeles Times]. The United States has authority over these waters because the tiny atolls and islands are U.S. territories.

The three areas are thronged with fish, sharks, coral reefs, and other forms of sea life, all of which will benefit from the new protections. Blue-water fish such as yellowfin, bigeye tuna, and marlin–all in decline–will be big winners because they breed in these waters. So will sharks, birds, turtles, and dolphins accidentally caught by the tuna long-line fleets [ScienceNOW Daily News]. One of the new national monuments also encompasses the deepest location of the earth’s crust. The Marianas Trench, which reaches depths of more than 36,000 feet in some locations, contains undersea volcanoes and hydrothermal vents around which cluster tough organisms that can withstand high temperatures and harsh chemicals. These “extremophiles” are of interest to scientists who think they signal forms that extraterrestrial life could take.

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The health benefits of eating more fish outweigh the risks of mercury poisoning, according to a new Food and Drug Administration (FDA) proposal that would revise current federal seafood advisories. The proposal is drawing fire from the Environmental Protection Agency (EPA) and environmental groups that accuse the FDA of pandering to the seafood industry. Richard Wiles, director of an environmental advocacy group, said, “This is an astonishing, irresponsible document…It’s a commentary on how low FDA has sunk as an agency. It was once a fierce protector of America’s health, and now it’s nothing more than a patsy for polluters” [Washington Post].

Currently, the government advises young children, pregnant women, and women of child-bearing age to restrict overall fish consumption to 12 ounces per week and to avoid shark, swordfish, king mackerel and tilefish, which are known to have particularly high mercury levels. Mercury in the environment accumulates in fish and studies have linked the element to developmental problems in fetuses and young children as well as cardiovascular disease in adults. However, the new FDA report says recent studies suggest “a beneficial impact on fetal neurodevelopment from the mother’s consumption of fish, even though they contain methylmercury…The net effect is not necessarily adverse, and could in fact be beneficial” [AP]. The report argued that nutrients in fish, including omega-3 fatty acids, selenium and other minerals could boost a child’s IQ by three points [Washington Post]. The new analysis places ideal fish consumption—for optimal IQ-boosting—somewhere above 12 ounces per week.

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Massive swarms of jellyfish are a growing threat to swimmers, the fishing industry, and even the nuclear power industry, a new report argues, and it’s high time for scientists to begin researching the causes of the population boom and how to reverse the trend. The new report from the National Science Foundation may tend towards sensationalism (the report is titled “Jellyfish Gone Wild!!“), but the problem is very real. The report says more than 1,000 fist-sized comb jellies can be found in a cubic yard (meter) of Black Sea water during a bloom. They eat the eggs of fish and compete with them for food, wiping out the livelihoods of fishermen, according to the report [Reuters]. A big swarm of jellies can also burst a fishing net or poison and crush a load of captured fish, the report says, and their bodies can clog boat engines.

“When jellyfish populations run wild,” the NSF jellyboffins warn, “they may jam thousands of square miles with their pulsing, gelatinous bodies.” It seems that no less than half a billion “refrigerator sized” slimy horrors weighing 450 pounds each invade the Sea of Japan daily, while Australian waters are plagued with “deadly, peanut-sized” Jellybabies of Death [The Register]. Popular tourist beaches from Spain to Alabama have been closed in recent years when swarms of stinging jellies threatened to harm bathers. As for their impact on nuclear power: The report claims that swarms of jellies sometimes clog the water intake pipes of power plants, and notes that in 1999 just such an incident forced a power plant in the Philippines to shut down, which “plunged 40 million people into darkness and started rumors of a coup d’etat.”

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It’s a question that has fascinated scientists for decades: When sea turtles and salmon decides to give up the freedom of the open ocean and head back to their birthplaces to breed, how do they find their way back? Some species of sea turtle migrate thousands of miles across entire oceans back to their birthplaces after leaving more than 10 years earlier. And after hatching in rivers, salmon travel hundreds of miles out to sea before returning home to spawn years later [Press Association]. Now one researcher thinks he has the answer. Marine biologist Kenneth Lohmann believes that these marine animals can detect the distinctive magnetic fields of different spots and use them to navigate.

“What we’re proposing is the sea turtles and salmon, when they begin life, basically learn or imprint on the magnetic field that marks their home area,” he said. “They retain this information. And years later, when it is time for them to return, they are able to exploit this information in navigating back to their home area” [National Geographic News]. Lohman says this doesn’t contradict the existing theory that when salmon reach coastal waters, chemical scents guide them upriver to the particular stream where they were born; those olfactory cues probably have a limited range, he says, and couldn’t extend thousands of miles into the ocean to guide the salmon all the way home.

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It’s not just we humans who value consensus: A new study has shown that stickleback fish make better decisions when acting as a group than they do as individuals. Researchers set up a clever experiment in which the fish had to choose which leader to follow in the quest for food, giving them an option between a “good” choice and a “bad” choice. Based on earlier experiments, the study’s researchers had a pretty good idea about … stickleback preferences. Fat, evenly colored fish are regarded as healthy and strong, while scrawny fish mottled with black spots may be considered diseased. Coauthor Ashley Ward … says of these sticklebacks, “Fish like large leaders, well-fed leaders and unparasitized leaders” [Science News].

Researchers made a stickleback replica that looked healthy and fat as well as one that appeared bony and mottled, and put both into the fish tank. When shown the fish replicas, the other sticklebacks in the tank would approach and follow one of the two replicas, which were moved around by remote control. Following a certain fish would be their version of casting a ballot…. When just one fish chose its leader, the fish would make the right choice, picking the healthiest leader about 55 percent of the time. That number went up to 80 percent with the eight-fish electorate [LiveScience].

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Using boat, tags, nets, and submarines, marine biologists from 82 nations have been canvassing the oceans for the first Census of Marine Life, an ambitious effort to get a rough tally of all the creatures in the world’s oceans. The 10-year project is expected to conclude in 2010, and researchers say the broad survey will help them observe changes to marine ecosystems. Says co-senior scientist Ron O’Dor: “We are moving into this period of global warming, which is resulting in the acidification of the oceans, melting of the polar ice cap. We can use the first census as a benchmark to see what happens in the oceans over the next decade or more” [BBC News].

Although the project still has two years to go, researchers have already made a host of startling discoveries, many of which will be discussed this week at the World Conference on Marine Biodiversity in Valencia, Spain. In one study, researchers conducted a genetic analysis of deep sea octopuses from around the world, and determined that most descended from a common ancestor species that still lives near Antarctica. Researchers believe that octopuses started migrating to new ocean basins more than 30 million years ago when, as Antarctica cooled and a large icesheet grew, nature created a “thermohaline expressway,” a northbound flow of tasty frigid water with high salt and oxygen content. Isolated in new habitat conditions, many different species evolved; some octopuses, for example, losing their defensive ink sacs — pointless at perpetually dark depths [LiveScience].

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In a new study that’s already generating controversy, researchers tracked more than 1,000 young Pacific salmon on their first journey to the sea, and found that those battling dams on the Columbia River fared no worse than the young fish with an easier path to the sea on Canada’s free-flowing Fraser River. The findings seem to contradict many previous studies about dams: Conservationists have blamed these obstacles for a large share of the shrinking salmon populations in the Pacific Northwest, and engineers have spent billions trying to make the dams less damaging to salmon [Science News].

The study used implanted transmitters to follow the juvenile salmon, called smolts, on their trips downriver, and found that only about 25 percent of smolts in both the Columbia and the Fraser survived the voyage and made it to the ocean. But environmentalists and several salmon biologists pounced on the study, suggesting that industry funding might have biased the results. These critics question the value of comparing the two rivers and say that the study doesn’t even address what many think is the dams’ biggest effect: stressed smolts dying after they reach the ocean [Nature News].

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A new study of a the fossilized remains of the Tiktaalik, the “walking fish” that illuminates how swimming fish evolved into land-dwelling amphibians, shows that there was more to the transition than the switch from fins to limbs. The study shows that the head and braincase were changing, a mobile neck was emerging and a bone associated with underwater feeding and gill respiration was diminishing in size, a beginning of the bone’s adaptation for an eventual role in hearing for land animals [The New York Times].

The creature, dubbed Tiktaalik roseae — or, to be less formal, Fishapod — lived 375 million years ago 600 miles north of the Arctic Circle in a subtropical floodplain that eventually became Ellesmere Island, where it was discovered in 2004 [Wired News]. The fishapod has already earned its reputation as a “missing link” in evolutionary history due to its sturdy, jointed fins and its dual breathing system, with both gills and lungs. But the new study suggests that changes to the animal’s head and the development of the first neck also played a critical role in its evolution.

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Marine biologists have gotten the first footage ever of a school of fish living 4.8 miles beneath the ocean’s surface in the cold, pitch black, and fiercely pressurized habitat of the Pacific’s Japan Trench. A video shows the pale white hadal snailfish, officially known as Pseudoliparis amblystomopsis, happily wriggling around on the seabed, despite water pressure that the researchers say is equivalent to 1,600 elephants standing on the roof of a Mini.

The fish belong to a species previously known only from five pickled specimens trawled up by Russian scientists in the 1950s, said [researcher] Monty Priede [National Geographic News]. Priede’s team of British and Japanese researchers found the rare snailfish during their exploration of deep, narrow marine trenches in Pacific Ocean, and say it was the deepest ever sighting of live fish.

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Young bluefin tuna travel the wide, blue, Atlantic Ocean much more extensively than researchers had previously realized, and the new findings should influence how the declining tuna fisheries are managed, researchers say. According to a new study, juvenile tuna born in the Gulf of Mexico and in the Mediterranean both swim to the waters off the mid-Atlantic coast, where they mingle for a while before returning to their native grounds to breed.

Researchers used the chemical composition of the fishes‘ inner ears to determine which marine ecosystem they were born in, and found that nearly 60 percent of juvenile bluefin tuna off the coast of Maryland had come all the way from the Mediterranean. “If you are a fisherman from Maryland going out and seeing lots of juvenile bluefin tuna, you might think the population is fine,” [lead researcher David] Secor says. “But when you realise they are being subsidised from the Mediterranean, it gives you a different perspective” [New Scientist].

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In Africa’s Lake Victoria, researchers believe they’ve caught a fish population in the act of splitting into two distinct species. Researchers say this example of evolution-in-action is remarkable because the two sub-populations of fish aren’t geographically isolated and could theoretically interbreed, but adaptations to their vision are causing them to diverge.

Lead researcher Norihiro Okada and his colleagues had previously shown that cichlid fish in Lake Victoria’s shallow waters are bathed in bluer light, while the turbid water of the lake predominantly lets redder light filter down to fish living in deeper water. The researchers showed that the fish’s eyes have adapted to this difference so that fish that live in deeper water have a pigment in their eyes that is more sensitive to red light, while shallow-water fish have a pigment that’s sensitive to blue [Science News]. Okada’s new study, published in Nature [subscription required], shows that those eye adaptations have also affected mating patterns.

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Researchers have found the first small finger-like bones in the fins of a fish that lived 380 million years ago, about 15 million years before the first four-footed creatures, called tetrapods, clambered onto the land.

The finding upends the most recent theory of the evolution of digits: The need to adapt to swampy marshlands and terra firma, the theory went, is what drove the gradual shift through natural selection from fish fins suitable only for swimming to weight-bearing limbs with articulated joints. The study, however, reveals that rudimentary fingers were already present inside the fins of the shallow-water Panderichthys, a transitional species that was nonetheless more fish than tetrapod [The Daily Telegraph].

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Researchers may have found a away to avert the doom many predict for commercial fisheries around the world. A system in which individuals are apportioned a fixed share of each year’s catch shows great promise in averting the collapse of fish stocks, according to a new study, in contrast to traditional “open access” rules in which fishermen compete to bring in the biggest load. “Under open access, you have a free-for-all race to fish, which ultimately leads to collapse,” said [lead researcher] Christopher Costello…. “But when you allocate shares of the catch, then there is an incentive to protect the stock, which reduces collapse. We saw this across the globe” [Reuters].

The results are a rare bit of good news in the debate over what’s to be done about the world’s fisheries; in a previous study, researchers predicted that if overfishing, pollution and habitat destruction continue unabated, all of the world’s fisheries would collapse by 2048. A fishery is considered collapsed if catches fall to 10% of historic highs [Los Angeles Times].

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A federal judge declared that California’s water management system is jeopardizing the existence of the state’s salmon and steelhead, which have to navigate the complicated network on their journeys out to the ocean and back to their riverine spawning grounds. The judge’s ruling established that the canals and pumps that deliver water to 23 million Californians are causing “irreparable harm” to two salmon species, as well as the threatened Central Valley steelhead [AP].

The judge stopped short of ordering immediate remedies like storing more water behind Shasta Dam, which could be released later to help migrating fish. But the judge’s conclusions mean regulators will be forced to impose more protective conditions when they issue a new permit in March, lawyers said. “It’s a clear signal that business as usual in the Delta is not going to be acceptable,” said Kate Poole, a lawyer for the Natural Resources Defense Council [Contra Costa Times].

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When a male toadfish lying in the mud starts humming a love song to a female or grunting a threat to another male, he’s not only playing the mating game; he’s also giving humans a hint of the origins of language.

Researchers studied the brains of the rare vocalizing toadfish as well as its close relative, the midshipman fish, to see which neurons controlled their production of various sounds. They found the answer in a clump of of neurons that are shared by all vertebrates, suggesting that the ability to vocalize evolved around 400 million years ago, before the first fishapods crawled out of the sea. “I’m not saying fish have a language or are using higher powers of the brain,” [said lead researcher Andrew Bass]. “But some of the networks of neurons, nerve cells in the brain, are very ancient” [AP].

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