As the oceans warm, wide-ranging species will have an edge

Terra Daily via SPX: Marine species that already have large ranges are extending their territories fastest in response to climate change, according to new research from University of British Columbia biodiversity experts.

The study is one of the first comprehensive looks at how traits--other than thermal niche--impact marine animals' ability to respond to climate change. It could help improve global predictions of how different species redistribute as the oceans warm, and identify species in greatest jeopardy.

"We have a bit of a mystery as to why some animals are moving quickly into cooler waters, like the green sea urchin that is decimating kelp forests in Tasmania, while other species aren't moving at all," says UBC biodiversity researcher Jennifer Sunday, lead author of the study.

"Our findings indicate that animals which already have wide-latitudinal ranges, habitat generalists, and species with high adult mobility displayed the quickest and greatest range shifts. The flip side is that small-ranging species are in increased jeopardy as our planet's oceans continue to warm."....

Oscar (Astronotus ocellatus), a popular aquarium fish from South America, shot by Jón Helgi Jónsson (Amything), Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

All the world's oceans have plastic debris on their surface

Terra Daily via SPX: ...[S]urface waters of the oceans may not be the final destination of plastic debris since, as indicated by the study performed by the Malaspina Expedition, large amounts of microplastics could be passing to the marine food chain and the ocean floor. Results of the study, led by the University of Cadiz (Spain), have been published in the journal Proceedings of the National Academy of Sciences (PNAS).

Andres Cozar, researcher from the University of Cadiz, explains: "Ocean currents carry plastic objects which split into smaller and smaller fragments due to solar radiation. Those little pieces of plastic, known as microplastics, can last hundreds of years and were detected in 88% of the ocean surface sampled during the Malaspina Expedition 2010".

According to the study authors, the results obtained by the Malaspina Expedition show that the problem of plastic waste pollution has a global character. The major residues found are polyethylene and polypropylene, polymers used in the manufacture of everyday products like bags, food and beverage containers, kitchen utensils and toys, among others.

Cozar adds: "These microplastics have an influence on the behavior and the food chain of marine organisms. On one hand, the tiny plastic fragments often accumulate contaminants that, if swallowed, can be passed to organisms during digestion; without forgetting the gastrointestinal obstructions, which are another of the most common problems with this type of waste.

"On the other hand, the abundance of floating plastic fragments allows many small organisms to sail on them and colonize places they could not access to previously. But probably, most of the impacts taking place due to plastic pollution in the oceans are not yet known"....

A plastic bag looking like a jellyfish, shot by seegraswiese, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Deforestation starves fish

A press release from the University of Cambridge: Research shows forest debris that drains into lakes is an important contributor to freshwater food chains – bolstering fish diets to the extent that increased forest cover causes fish to get ‘fat’ and sparse forest leaves smaller, underfed fish. Debris from forests that washes into freshwater lakes supplements the diets of microscopic zooplankton and the fish that feed off them – creating larger and stronger fish, new research shows.

The researchers warn that, as forests are eroded through human activities such as logging, the impacts will be felt in aquatic as well as terrestrial food chains. In fact, the study was conducted at a Canadian lake chosen because it had suffered ecological disaster during the mid-20th century: acid rain as a result of the local nickel smelting industry.

Despite moves to reduce environmental impact, many areas of vegetation surrounding the lake are still in recovery. This enabled scientists to study Yellow Perch fish from different parts of a lake that has varying degrees of surrounding forest coverage.

Carbon from forest debris has a different elemental mass than carbon produced by algae in the aquatic food chain. By analysing the young Perch that had been born that year, scientists were able to determine that at least 34% of the fish biomass comes from vegetation, increasing to 66% in areas surrounded by rich forest. Essentially, the more forest around the edge of the lake, the fatter the fish in that part of the lake were.

Scientists say that the young fish in lake areas with scant forest cover were much smaller, and consequently much less likely to survive and breed. “We found fish that had almost 70% of their biomass made from carbon that came from trees and leaves instead of aquatic food chain sources,” said Dr Andrew Tanentzap from Cambridge’s Department of Plant Sciences, and lead author of the new study, published today in the journal Nature Communications....

US Fish and Wildlife image of yellow perch 

Making dams safer for fish around the world

Tom Rickey at the Pacific Northwest National Laboratory: Think of the pressure change you feel when an elevator zips you up multiple floors in a tall building. Imagine how you'd feel if that elevator carried you all the way up to the top of Mt. Everest — in the blink of an eye. That's similar to what many fish experience when they travel through the turbulent waters near a dam. For some, the change in pressure is simply too big, too fast, and they die or are seriously injured.

In an article in the March issue of the journal Fisheries, ecologists from the Department of Energy's Pacific Northwest National Laboratory and colleagues from around the world explore ways to protect fish from the phenomenon, known as barotrauma.

Among the findings: Modifying turbines to minimize dramatic shifts in pressure offers an important way to keep fish safe when passing through dams. The research is part of a promising body of work that aims to reduce such injuries by improving turbine designs in dams around the world.

PNNL researchers are working with officials and scientists from Laos, Brazil, and Australia — areas where hydropower is booming — to apply lessons learned from experience in the Pacific Northwest, where salmon is king and water provides about two-thirds of the region's power. There, billions of dollars have been spent since 1950 to save salmon endangered largely by the environmental impact of hydropower.

"Hydropower is a tremendous resource, often available in areas far from other sources of power, and critical to the future of many people around the globe," said Richard Brown, a senior research scientist at PNNL and the lead author of the Fisheries paper. "We want to help minimize the risk to fish while making it possible to bring power to schools, hospitals, and areas that desperately need it," added Brown....

A sluice at Brazil's Itaipu Dam, shot by Herr stahlhoefer, public domain

Myanmar's fish farms suffer amid early heat wave

Myat Nyein Aye in the Myanmar Times:   Unseasonable early heat and freshwater parasites that thrive in hotter water temperatures are devastating fish farms throughout Myanmar, an official from the Myanmar Fish Farmer Association said. “Starting on February 9, the temperature shot up unexpectedly, so many farmers’ fish pools dried up and the fish died as a result of lack of oxygen. Also, deadly parasites tend to grow in fish farms when the temperature increases,” U Soe Tint, the Association’s vice chairman, told The Myanmar Times on February 21.

While fish farmers normally wait to harvest their fish until monsoon season from June until October, they are harvesting their fish now in fear that they will die from the heat or parasites.

The most common parasite affecting fish farms is dactylogyrus, a flatworm known to inhabit fish gills, the Association said. The parasite is temperature dependent: Hotter water temperatures increase the parasite’s life cycle from only a few days to five or six months. Anti-parasitic medicine can be bought from China or Thailand and costs about K250,000 (about US$290).

“Fish farmers who did not use medicine for parasites face higher losses. I used the medicine after suffering about K300,000 (about US$350) in losses when my fish died,” U Soe Tint said, who has a fish farm in Yangon Region’s Twantay township...

EU states close to agreeing on greater local say in managing fisheries

Fiona Harvey in the Guardian (UK): Proposals to give European Union member states a greater say over how their fisheries are managed moved a step closer to acceptance on Friday, as part of a wider package of reforms that represent the biggest shakeup of the fishing industry in decades.

The meeting of the EU Fisheries Council in Luxemburg concluded without major upset, giving ministers the chance to concentrate in future meetings on the more controversial components of the package, such as the proposal to ban the wasteful practice of discarding edible fish at sea.

Giving member states greater powers over how to manage their fisheries is broadly popular with national governments. It could help to defuse tension over how the total catch in the EU's fisheries should be divided into quotas for each country.

Richard Benyon, the UK fisheries minister, said the meeting had made "progress, but there's still a long way to go" on the full package of measures.

He said: "We are in favour of greater localisation because it will lead to better management of fisheries – the situation in the western Mediterranean, for instance, is very different to that in the North Sea, and the centralisation of powers in the hands of the European Commission does not always reflect that."...

A mackerel caught in the Belgian part of the North Sea, shot by Hans Hillewaert, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Expert task force recommends halving global fishing for crucial prey species

Science Daily: Fishing for herring, anchovy, and other "forage fish" in general should be cut in half globally to account for their critical role as food for larger species, recommends an expert group of marine scientists in a recent report. The Lenfest Forage Fish Task Force conducted the most comprehensive worldwide analysis of the science and management of forage fish populations to date. Its report, "Little Fish, Big Impact: Managing a crucial link in ocean food webs," concluded that in most ecosystems at least twice as many of these species should be left in the ocean as conventional practice.

A thriving marine ecosystem relies on plenty of forage fish. These small schooling fish are a crucial link in ocean food webs because they eat tiny plants and animals, called plankton, and are preyed upon by animals such as penguins, whales, seals, puffins, and dolphins. They are primary food sources for many commercially and recreationally valuable fish found around North America, such as salmon, tuna, striped bass, and cod. The task force estimated that, globally, forage fish are twice as valuable in the water as in a net -- contributing US$11.3 billion by serving as food for other commercially important fish. This is more than double the US$5.6 billion they generate as direct catch.

These species play a growing role in the everyday lives of industrialized nations. Their demand in recent decades has greatly increased for use as fish meal and fish oil to feed farmed fish, pigs, and chickens that people consume on a regular basis. Fish oil is also used in nutritional supplements for humans....

A school of fish at the California Academy of Sciences, shot by Toby Hudson, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Ancient civilizations reveal ways to manage fisheries for sustainability

A press release from Wiley Publishing: In the search for sustainability of the ocean’s fisheries, solutions can be found in a surprising place: the ancient past. In a study to be published March 23 in the journal Fish and Fisheries, a team of marine scientists reconstructed fisheries yields over seven centuries of human habitation in Hawaii and the Florida Keys, the largest coral reef ecosystems in the United States, and evaluated the management strategies associated with periods of sustainability. The results surprised them.

“Before European contact, Native Hawaiians were catching fish at rates that far exceed what reefs currently provide society,” said John “Jack” N. Kittinger, co-author and an early career fellow at the Center for Ocean Solutions at Stanford University. “These results show us that fisheries can be both highly productive and sustainable, if they're managed effectively.” In contrast, historical fisheries in Florida were characterized by boom and bust, with serial depletions of highly valuable species for export markets. Today many species that were the target of 19th and early 20th century fisheries in Florida - including green turtles, sawfish, conch and groupers - have severely reduced populations or are in danger of extinction.

“Seven hundred years of history clearly demonstrate that management matters,” said Loren McClenachan, co-author and assistant professor of Environmental Studies at Colby College. "Ancient Hawaiian societies used sophisticated tools similar to innovative conservation strategies used today, like marine protected areas and restrictions on harvest of vulnerable species like sharks.” The difference, the authors explained, was in the way fisheries governance systems were structured. Regulations were developed locally with the buy-in of community members, but they were also effectively enforced with methods that now would be considered draconian. “Today, no management system comes close to achieving this balance, and as a result, resource depletion and collapse is common,” said McClenachan...

Overfishing leaves swaths of Mediterranean barren

Terra Daily via SPX: Centuries of overexploitation of fish and other marine resources - as well as invasion of fish from the Red Sea - have turned some formerly healthy ecosystems of the Mediterranean Sea into barren places, an unprecedented study of the Mediterranean concludes.

Research by an international team of scientists designed to measure the impact of marine reserves found that the healthiest places were in well-enforced marine reserves; fish biomass there had recovered from overfishing to levels five to 10 times greater than that of fished areas.

However, marine "protected" areas where some types of fishing are allowed did not do better than sites that were completely unprotected. This suggests that full recovery of Mediterranean marine life requires fully protected reserves, the scientists write in a paper published Feb. 29, 2012, in the journal PLoS ONE.

"We found a huge gradient, an enormous contrast. In reserves off Spain and Italy, we found the largest fish biomass in the Mediterranean," said National Geographic Explorer-in-Residence Enric Sala, the paper's lead author. "Unfortunately, around Turkey and Greece, the waters were bare."...

A fishing boat in Palermo, shot by Filippo, Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license

A damming assessment of Mekong development

Jane Qiu in Nature: Dams on the tributaries of the Mekong River could have a greater negative effect on fish biodiversity and food security than those on the main river, researchers say. Hydropower developments on Mekong tributaries are not subject to the same level of scrutiny as their counterparts on the main river. “Most of the attention has been on proposed dams on the Mekong mainstream, such as the highly controversial Xayaburi dam in Laos,” says lead author Guy Ziv, an environmental scientist now at Stanford University in California. “The impact of tributary dams is little studied.”

The findings, published today in Proceedings of the National Academy of Sciences1, “point to a desperate need to reconsider hydropower development in the entire Mekong River basin”, says Ame Trandem, the Southeast Asia programme director for the environmental group International Rivers in Bangkok.

With a watershed of 800,000 square kilometres, the Mekong River basin supports the world’s largest inland fishery and is home to 65 million people in six countries: China, Myanmar, Laos, Thailand, Vietnam and Cambodia. “Most of the people are poor and get 81% of their protein from subsistence fisheries,” says Ziv.

The steep topography of the region makes the Mekong an attractive place for hydropower development. Driven by increasing demand for electricity and a desire for economic development, 11 dams are being planned on the main river, with 41 on the tributaries expected to be completed within the next 4 years. Another 10–37 tributary dams are likely to be built between 2015 and 2030....

Gia Long waterfall in Srepok River, Dak Lak, Vietnam, shot by Đỗ Tuấn Hưng, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Pacific fisheries need tech to track climate impact

Johann Bell in SciDev.net: Climate change could derail plans by Pacific Island countries and territories (PICTs) to use fisheries and aquaculture to foster economic development and food security. Bottom-dwelling coastal fish are expected to be hardest hit. Under continued high emissions of greenhouse gases, stocks of these fish are estimated to decrease by 20 per cent by 2050 due to global warming and ocean acidification, which affect the fish themselves as well as the coral reefs that support them.

But much uncertainty remains about the impacts of climate change. And contrary to assessments for some other parts of the world, the projections for fisheries and aquaculture in the Pacific are not all negative. In particular, tuna stocks are expected to rise in the eastern Pacific, and increased rainfall is likely to improve the production of freshwater fisheries and pond aquaculture in the western Pacific.

Indeed, many communities could switch their fishing efforts to tuna that frequent coastal waters. By installing anchored fish aggregating devices (FADs) to temporarily hold tuna, small-scale fishers could access these valuable resources more easily.

Building networks of inshore FADs to increase coastal communities' access to tuna is an example of a 'win-win adaptation': it will help supply the additional fish needed by growing populations in ways that are likely to be favoured by climate change....

Nice picture, wrong ocean. Casting a net in Kerala, India, shot by Challiyil Eswaramangalath Vipin, Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license

Expanding dead zones are shrinking tropical blue marlin habitat

Science Daily: The science behind counting fish in the ocean to measure their abundance has never been simple. A new scientific paper authored by NOAA Fisheries biologist Eric Prince, Ph.D., and eight other scientists shows that expanding ocean dead zones -- driven by climate change -- have added a new wrinkle to that science.

In the December 4 paper published in the scientific journal Nature Climate Change, these scientists sound an alarm that expanding ocean dead zones are shrinking the habitat for high value fish such as marlins in the tropical northeast Atlantic Ocean. As dead zones expand, marlins, other billfish and tunas move into surface waters where they are more vulnerable to fishing. Dead zones are areas in the ocean where oxygen levels are so low that creatures cannot survive over the long term.

"By combining the disciplines of oceanography and fishery biology, we are getting a much clearer picture of how climate driven dead zones are shrinking the habitat for some of the world's most valuable fish to commercial and recreational fishermen," Prince said. "With a clearer picture, we will be able to make better management decisions for the long-term health of these species and their ecosystems."

...Blue marlins and many other billfish are high energy fish that need large amounts of dissolved oxygen. By comparing the movement of the blue marlins and the location of low-oxygen areas, the scientists show that blue marlins venture deeper when dissolved oxygen levels are higher and remain in shallower surface waters when low dissolved oxygen areas encroach on their habitat from below.

"The shrinking of habitat due to expanding dead zones needs to be taken into account in scientific stock assessments and management decisions for tropical pelagic billfish and tuna," said Prince. "Without taking it into account, stock assessments could be providing false signals that stocks are healthy, when in fact they are not, thus allowing overfishing that further depletes these fish stocks and threatens the sustainability of our fisheries."...

Atlantic blue marlin, image from NOAA

New biomass data reveals fish stocks more stable than believed

Terra Daily: Fish and marine species are among the most threatened wildlife on earth, due partly to over exploitation by fishing fleets. Yet there are differences in assessing trends in worldwide fishing stocks which, researchers writing in Conservation Biology argue, stem from inappropriate use of time trends in catches.

"Estimates of fishery status based on catches suggest that around 30% of fisheries are collapsed and 70% are overexploited or collapsed," said lead author Dr Trevor Branch from the University of Washington in Seattle. "Our assessment shows that the data are seriously biased, and that instead we should be looking at biomass data."

Biomass data from scientific stock assessments indicated a much smaller proportion in these categories (12% collapsed, 26% overexploited or collapsed), and that status trends are stable. Dr Branch's analysis suggests that in most regions fisheries management has led to stabilization, and even recovery, of fished populations.

"Species which are targeted by fishing fleets are divided into stocks, a division of species into units based on political boundaries, genetic divergence, and biological characteristics," said Branch. "The depletion of these stocks has important implications for ecosystem biodiversity; however methods of measuring depletion vary greatly."

Dr Branch's team considered stocks being "collapsed" or "overexploited" on the basis of catch and biomass data. Collapse is defined as biomass of less than 10% of unfished levels while over exploitation is defined by the governments of the United States and Australia as biomass below 50% of biomass that would produce maximum sustained catches. These reference points are widely used in fisheries management, either as management targets or as limits not to be exceeded….

Fish in net, shot by Joseolgon, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Invasive lionfish now found from Bahamas to New England

Environment News Service: The rapid spread of invasive lionfish along the U.S. eastern seaboard, Gulf of Mexico, and Caribbean is the first documented case of a non-native marine fish establishing a self-sustaining population in the region, a U.S. Geological Survey marine expert said today. "Nothing like this has been seen before in these waters," said Dr. Pam Schofield, a biologist with the USGS Southeast Ecological Science Center in Gainsville.

More than 30 species of non-native marine fishes have been sighted off the coast of Florida alone, but until now none of these have demonstrated the ability to survive, reproduce, and spread successfully. "We've observed sightings of numerous non-native species, but the extent and speed with which lionfish have spread has been unprecedented," Schofield said. "Lionfishes pretty much blanketed the Caribbean in three short years."

Indo-pacific red lionfish, Pterois volitans, originally came from the Indo-West Pacific Ocean. They were first reported off Florida's Atlantic coast in the mid-1980s, but did not become numerous in the region until 2000. Since then, lionfishes have been documented along the entire U.S. east coast from Florida to Massachusetts, east to Bermuda and south throughout the Bahamas and in other Caribbean nations such as Turks and Caicos and Cuba.

…"This invasion may constitute a harbinger of the emerging threat of non-native marine fishes to coastal systems," Schofield said....

Lionfish, or Pterois volitans, shot by Albert Kok, who has released the image into the public domain

Dust from Africa may increase risk of seafood poisoning

Richard Gray in the Telegraph (UK): Researchers have found that harmful bacteria found in seawater flourish in the presence of dust that comes from the Sahara desert in western Africa, as well as other areas of continent. They warn that as climate change causes such desert areas to grow, the risk of seafood poisoning could rise around the world.

At the same time, rising sea temperatures could further increase the chances of these bacteria occurring in shellfish caught in British waters. Huge quantities of the dust can be carried long distances across the sea by the trade winds. Although much of it is deposited in the Caribbean, the Gulf of Mexico and the Mediterranean, some reaches northern Europe and the UK, where it can sometimes be found forming a thin layer on car windscreens.

Dr Erin Lipp, from the University of Georgia, said that species of harmful bacteria including Vibrio parahaemolyticus, Vibrio alginolyticus, Vibrio vulnificus and even cholera showed significant growth spurts two days after African desert dust was added to the water they grew in. She said: "We focused on desert areas in western Africa that are likely to grow over the coming century due to climate change. Dust storms in these areas are also projected to increase and with them, the transport of dust across the Atlantic Ocean basin."
Dr Lipp, who presented the findings at the American Association for the Advancement of Science annual meeting in Washington on Saturday, added: "Our results suggest that in addition to rising sea surface temperatures, increased global production and oceanic deposition of desert dust may have a significant affect on key marine pathogens and may ultimately increase exposure rates and infection risk in humans. "We saw a 10 to 1,000-fold growth in Vibrios, including one strain that could cause eye, ear, and open wound infections, and another strain that could cause cholera."

Desert dust can lead to huge booms in sea life as it helps to nourish the water but the new findings could also now be used to help predict when shellfish from different regions are most at risk of causing food poisoning outbreaks…

A dust plume off the coast of West Africa

Hammerheads, other sharks protected at fisheries meet

Terra Daily via AFP: Half-a-dozen species of endangered sharks hunted on the high seas to satisfy a burgeoning Asian market for sharkfin soup are now protected in the Atlantic, a fisheries group decided Saturday.

Scalloped, smooth and great hammerheads, along with oceanic white tip, cannot be targeted or kept if caught accidentally, the International Commission for the Conservation of Atlantic Tunas (ICCAT) said.

Three other types of hammerhead are included in the ban: smalleye, scoophead, and whitefin. However, a proposal submitted by the European Union to extend the same level of protection to the porbeagle shark, critically endangered in the northeast Atlantic and Mediterranean, was shot down….

Great hammerhead (Sphyrna mokarran) at the Adventure Aquarium, Camden, NJ, USA, shot by Jim Capaldi, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license

Huge fish kill in Louisiana

Bob Warren in the New Orleans Times-Picayune: Plaquemines Parish officials have asked state wildlife officials to investigate what they said is a massive fish kill at Bayou Chaland on the west side of the Mississippi River late Friday. The fish kill was reported to the Louisiana Department of Wildlife & Fisheries and the cause has not yet been determined, the parish said. The fish were found in an area that has been impacted by the oil from the BP oil spill, the parish said.

The dead fish include pogies, redfish, drum, crabs, shrimp and freshwater eel, the parish said. Plaquemines Parish President Billy Nungesser said he has asked Wildlife & Fisheries for a quick determination of the cause. The parish has also requested testing by the U.S. Environmental Protection Agency and National Oceanic and Atmospheric Administration….

An 1814 map of Louisiana

Cold blamed for Bolivia's mass fish deaths

Anna Petherick in Nature News: With high Andean peaks and a humid tropical forest, Bolivia is a country of ecological extremes. But the unusually low winter temperatures experienced by the country's tropical region in July and August hit freshwater species hard, killing an estimated 6 million fish and thousands of alligators, turtles and river dolphins.

Scientists who have visited the affected rivers say the event is the biggest ecological disaster Bolivia has known. They are now scrambling to coordinate research into how it happened, and how quickly the ecosystem may recover. … Decomposing fish have polluted the waters of the Grande, Pirai and Ichilo rivers so badly that local authorities have had to provide alternative sources of drinking water for towns along the rivers' banks.

The blame lies with a mass of Antarctic air that settled over the Southern Cone of South America for most of July. Water temperatures in Bolivian rivers that normally register about 15 °C during the day fell as low as 4 °C.

"It is not unlikely that the extreme weather conditions in July might have been related to the El Niño–Southern Oscillation [ENSO]," says Fons Smolders, a fisheries scientist at Radboud University in Nijmegen, the Netherlands. "Although it is still debated whether ENSO is affected by climate change, it is generally accepted that climate change has the potential to increase the prevalence and severity of extremes such as heat waves, cold waves, storms, floods and droughts….

Fish farming in Lake Titicaca, Bolivia, shot by Christopher Walker, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license

Warming waters exacerbate dwindling New England fisheries

Scientific American: ….Many fishermen here feel threatened by a sweeping new set of fishing limits imposed this spring by authorities trying to rebuild fish stocks they say are depleted by overfishing and facing pressures that include climate change. Federal fishing regulators have traditionally reacted to falling stocks by putting additional curbs on fishing. But that approach may not work in the face of larger environmental changes such as global warming.

The chief fishing grounds for Massachusetts watermen are Gulf of Maine and the Georges Bank, the most westward of the famous Atlantic fishing banks off the North American coast. They are among the most famous and historically productive fishing grounds in the world; their collapse in the mid-1990s was equally historic, and the debate over how to manage the depleted stocks while nursing them back to health has been hotly contested ever since.

But the arguments are changing as scientists see more evidence of the coming impact of climate change on the Atlantic fisheries. Both the Gulf of Maine and the Georges Bank sit at the southern edge of the cod's preferred range. Fishermen have adapted to stock changes over the years, but their options may be dwindling.

"The question of the influence of fishing and the influence of the environment is tangled up," said Brian Rothschild, a professor of marine science at the University of Massachusetts, Dartmouth, who has studied aquatic stocks for more than five decades.

"There is no question that as some of the environment changes occur, some of the fish stocks are going to change," he said. "We don't know enough about it to know what's going to increase and what's going to decrease."

That gives a gloomy uncertainty to the future for New England commercial fishermen. There were an estimated 2,000 working fishermen in Gloucester in the 1940s; 50 years later the number had dropped to 400, according to a 1997 study. Fishermen glumly expect their numbers to continue to shrink….

"The Steam Ship President, The Largest in the World. Lieut. Roberts R.N. commander on her last voyage from New York to Liverpool. As last seen from the Packet Ship ORPHEUS Capt. COLE in the terrific gale of March the 12th 1841 ...She was then situated in that dangerous part of the Atlantic Ocean about midway between the Nantucket Shoal and the St. George's Bank, just where the Gulf Stream strikes soundings, and where the waves rise almost straight up & down & as high as a four or five story house...."

Europe's fishing industry 'unsustainable' as stocks drop

David Adam in the Guardian (UK): Europeans are eating more fish while stocks in their own seas continue to deplete, according to a new analysis that highlights the unsustainable nature of the industry. A report from the New Economics Foundation (NEF) names today as the point at which Europe has nominally consumed all its own fish, and needs to bring in stocks from elsewhere. The thinktank says this "fish dependence day" comes earlier than in previous years, which it says shows that policy changes are needed.

The report, Fish Dependence: The Increasing Reliance of the EU on Fish From Elsewhere, maps marine resources onto a calendar year, and finds the day when the EU effectively starts to live off the rest of the world. This point now arrives a month earlier than when the group performed a similar analysis in 2000.

Aniol Esteban, head of environmental economics at NEF, said: "Safeguarding the marine environment is vital if we want to make use of EU resources and protect livelihoods and economies."

Esteban added: "The EU has some of the largest and richest fishing grounds in the world but at the moment we're not managing them properly. The upcoming reform of the EU's common fisheries policy presents a unique opportunity to ensure that these ecosystems are protected for future generations."…

A European perch, shot by Lauri Rantala, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license