The most extensive survey of pH levels in the Pacific Ocean confirms what spot measurements have suggested: From Hawaii to Alaska, the upper reaches of the sea are becoming more acidic in concert with rising carbon dioxide in the atmosphere."If you see these changes across an entire ocean basin, you can be assured it's happening on a global scale in other ocean basins around the world," said Robert Byrne, a marine chemist at the University of South Florida and lead author of an upcoming paper in Geophysical Research Letters.Ocean acidification is a threat to shelled creatures and other marine life, and is a leading suspect in the ongoing crash of Pacific oyster populations in Washington.Byrne collaborated with Seattle scientists on the survey, which was 15 years in the making. The team first measured acidity along the 2,800-mile sweep of ocean between Oahu and Kodiak in 1991. They returned in 2006 aboard the University of Washington research vessel Thomas G. Thompson, working around the clock in shifts to collect and analyze nearly 1,500 water samples over two months.It's the first time measurements have been taken across such a wide area, said co-author Richard Feely, of the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory in Seattle."The fact that we saw this very significant change over the last 15 years is a reminder of how mankind is affecting the oceans at an ever-increasing rate," Feely said.In addition to contributing to a global greenhouse effect, some of the carbon dioxide from cars, factories and power plants dissolves in the ocean, creating the same carbonic acid that gives soda pop its tang. The process makes seawater slightly more acidic, and also gobbles up carbonate, a basic building block of seashells.The result can be an environment where shells dissolve, destroying plankton, marine snails and other small creatures that sustain the rest of the marine food web. Acidified water also can kill fish eggs and larvae.Byrne and his colleagues developed a more precise way to measure pH, using a dye that turns from purple to bright yellow as acidity increases. On board the ship, they used instruments called spectrophotometers to measure the color change and nail pH levels 10 times more accurately than possible before.Debby Ianson, an ocean climate modeler for Canada's Institute of Ocean Sciences who was not involved in the project, said the approach is a good one. "We need studies like this," she wrote in an e-mail.As expected, the researchers found acidification was strongest in the top layer of water, closest to the atmosphere. Normal seawater is slightly alkaline, with a pH value of about 8. Over the past 15 years, average pH levels in the top 300 feet of the ocean dropped 0.026 pH units. That sounds tiny, but is equivalent to a 6 percent jump in acidity, Byrne said.Working a thousand or more miles off the West Coast, the scientists took samples down to the ocean floor. They found no change yet in acidity at the deepest levels. But as carbon-dioxide levels in the atmosphere continue to climb, natural mixing eventually will raise acidity throughout the water column, Byrne said.Analysis of air bubbles trapped in Antarctic ice cores show that atmospheric carbon dioxide already is higher than anytime in the last 800,000 years, and the same is almost certainly true of ocean acidity, Byrne pointed out. Since the start of the Industrial Age, the scientists calculate that the acidity of the world's oceans has increased by 25 to 30 percent.Under a business-as-usual scenario, Feely said, ocean acidity could triple by the end of the century.Ianson cautions that extrapolating future rates of acidification is difficult, because the ocean and atmosphere are so complex.Still, Byrne said, the trend is clear."We're seeing unprecedented rates of change in the atmosphere, and we're going to see changes in seawater in lock-step with that," he said.
Showing posts with label Marine life. Show all posts
Showing posts with label Marine life. Show all posts
Monday, January 25, 2010
Thursday, January 07, 2010
Impact of Unsettled Summer Weather on UK Marine Life
A recent scientific conference has provided new evidence for the effects of unseasonal summer storms on a variety of spectacular marine life, including deadly jellyfish, basking sharks and oceanic seabirds.
The third annual 'South West Marine Ecosystems' meeting, held in Plymouth in December 2009, brought together 40 representatives from the scientific, conservation, fishing and eco-tourism sectors. The aim was to discuss impacts of environmental change and conservation measures on marine life off southwest England.
A common theme was the influence of a third successive summer dominated by wet and windy weather, with southwest England particularly affected by a series of Atlantic storms. This led to an unprecedented mid-summer influx of the deadly Portuguese man-o-war jellyfish onto Cornish beaches, leading to temporary closure of some popular tourist hotspots such as Sennen Cove.
The stormy conditions also blew in record numbers of the Wilson's storm petrel, a tiny oceanic seabird that breeds in the southern Atlantic Ocean and is traditionally a very rare visitor to UK coasts. Several sightings of the spectacular black-browed albatross were also made during the summer and autumn, including the first in Cornwall for over 20 years.
Meeting organiser, Dr Russell Wynn of National Oceanography Centre, Southampton (NOCS) said: "The effect of these mid-summer storms on our marine life has been dramatic. If recent summers are an indication of future trends, then we might expect to see more exotic visitors around our coasts in the years to come."
However, the unsettled weather was bad news for basking sharks, which were only seen in very low numbers off southwest UK through the summer and autumn. During stormy conditions, their plankton prey is widely scattered, and it is believed that the sharks move further north and west in search of more productive waters at these times. In addition, the RSPB reported that the wet, cold conditions could be contributing to low productivity of breeding seabirds such as kittiwakes.
Helen Booker of RSPB said "Mid-summer storms are a particular problem for our breeding kittiwakes, which nest on exposed cliffs and headlands. The adult birds have difficulty finding food in very rough seas, while the chicks are vulnerable to chilling in persistently cold, damp conditions."
Conservation topics discussed at the meeting included a study on threatened seahorses in Studland Bay, Dorset, the establishment of a network of Marine Conservation Zones around our coasts, and ongoing efforts to reduce dolphin strandings and bycatch in southwest England.
South West Marine Ecosystems is an annual meeting that has run since 2007, and is organised by NOCS and the Sir Alister Hardy Foundation for Ocean Science (SAHFOS).
Monday, November 23, 2009
Acid oceans leave fish at more risk from predators
Clown fish reared in acidified water lost the ability to "smell" danger Ocean acidification could cause fish to become "fatally attracted" to their predators, according to scientists.A team studying the effects of acidification - caused by dissolved CO2 - on ocean reefs found that it leaves fish unable to "smell danger". Young clownfish that were reared in the acidified water became attracted to rather than repelled by the chemical signals released by predatory fish. The findings were published in the journal Ecology Letters. Danielle Dixson from James Cook University in Queensland, Australia, led the study. She and her colleagues tested orange clown fish larvae that were raised in water with the same slightly alkaline pH as their ocean reef habitat, and those raised in more acidic water. The team released the fish into a "flow chamber" with two water sources flowing in parallel. One source was taken from tanks containing the clown fishes' natural predators and one was drawn from tanks in which non-predatory fish were swimming. "The flow rates are identical, so the water won't mix," Ms Dixson explained. "This allows the fish in the chamber to choose which water cue they prefer or dislike." In the test, the fish reared in normal water avoided the stream of water that their predators had been swimming in. They detected the odour of a predator and swam away from it. But, Ms Dixson said, fish raised in the more acidic water were strongly attracted to both the predatory and the non-predatory flumes. The researchers say that their study shows that fish larvae "might exhibit a fatal attraction to predators at CO2 and pH levels that could occur in our oceans by 2100 on a business-as-usual scenario of greenhouse gas emissions". Smell of dangerPrevious studies have shown that fish rely on their sense of smell, or olfaction, to avoid being eaten during the what is known as their settlement process. This is when the recently hatched larvae find a suitable, and safe, place to live. At this vulnerable juvenile stage, the researchers pointed out, "the ability to detect and avoid predators is one of the most important mechanisms to ensure survival". Ms Dixson told BBC News: "Ocean acidification has the potential to become a widespread problem and it's unknown how many organisms and ecosystems will cope with the decrease [in] pH. "This study shows that ocean acidification could lead to an increase in the mortality of larvae."BBC
Tuesday, October 20, 2009
New Insights Into Marine Ecosystems And Fisheries Production
NOAA and Norwegian researchers recently completed a comparative analysis of marine ecosystems in the North Atlantic and North Pacific to see what factors support fisheries production, leading to new insights that could improve fishery management plans and the ecosystems.
Known as MENU, for Marine Ecosystems of Norway and the U.S., the collaborative project involved scientists at the NOAA Fisheries Service’s Northeast Fisheries Science Center and Alaska Fisheries Science Center and colleagues at the Institute of Marine Research in Norway. Results of their analyses, funded by the Norwegian Research Council, were recently published in a special issue of the journal Progress in Oceanography.
“We used some innovative statistical methods and approaches, applying these over different space and time scales to compare multiple ecosystems,” said Jason Link of the Northeast Fisheries Science Center lab in Woods Hole, Mass., who served as a guest editor of the issue and is a co-author of several of the 17 research articles.
"Other comparative ecosystem studies have been conducted, but most have involved applying a single statistical model to multiple systems or multiple models to one ecosystem. MENU is the first attempt to provide a comprehensive, coordinated and integrated view of a wide range of marine ecosystems.”
Researchers involved in MENU and in other comparative analyses found underlying patterns in the ecosystems that would not have been apparent had only one ecosystem been studied. For example, MENU results revealed that deeper eastern ocean boundary systems, like those off Alaska or in the eastern North Atlantic off Europe, are more strongly influenced by bottom-up mechanisms, known as forcing. These would include broad scale oceanographic systems like the Pacific Decadal Oscillation and the El Nino Southern Oscillation.
Shallower western boundary systems, mainly on continental shelves, like Georges Bank and other areas off the east coast of the U.S. and Canada, are more strongly influenced by top-down processes, such as fisheries exploitation. "Both top-down and bottom-up processes occur in all of these ecosystems, but being able to determine their relative importance is difficult.," Link said.
The researchers compared marine ecosystems in the northern hemisphere and mostly in high latitudes, ranging from the eastern Bering Sea and Gulf of Alaska in the North Pacific to Georges Bank and the Gulf of Maine, North Sea and the Adriatic Sea off Italy. Other ecosystems studied included the Gulf of St. Lawrence, Scotian Shelf, Newfoundland Shelf, Southern New England, Gulf of Finland, and the Baltic Sea. All of these ecosystems support commercially important fisheries.
Fisheries landings in the ecosystems studied appear to have shifted from groundfish to invertebrates, such as squid, shrimp and scallops. In many, the fish community has changed from one dominated by demersal or bottom-dwelling species to one dominated by pelagic or upper water column species. The researchers note that it is unclear if their findings are true of all marine ecosystems, or just those studied. One of the many questions raised by the comparative analyses is whether similar species in different ecosystems react to environmental conditions in similar ways, or whether the local ecosystems override global factors.
Fisheries production varies widely among ecosystems, and is affected by changing natural and human-induced factors such as climate, pollution and fishing effort. With so many factors involved, Link said scientists need to understand the relative importance of each factor in each ecosystem, something that is difficult to achive but important for an ecosystem approach to fisheries management and conservation.
“We do a lot of science, but rarely have the opportunity to pull it all together to understand the big picture, with basin-scale comparisons, so that we can start to understand processes within an ecosystem as well as between ecosystems,” Link said. “Since we cannot conduct experiments in large marine ecosystems, we used the comparative approach in MENU as a natural experiment to address a number of questions. Among these are what is fundamental to ecosystems in general, and what is unique to particular ecosystems?”
Scientists are already undertaking more integrated ecosystem assessments like MENU in the U.S. to build on decades of smaller scale, more focused studies on individual ecosystems. Comparative Analysis of Marine Ecosystem Organization, or CAMEO, is a partnership between NOAA’s Fisheries Service and the National Science Foundation to advance understanding of marine ecological systems using a comparative approach. CAMEO funded seven projects for 2008-2009 and is currently soliciting research proposals for 2009-2010.
Adapted from materials provided by NOAA Fisheries Northeast Fisheries Science Center.
“We used some innovative statistical methods and approaches, applying these over different space and time scales to compare multiple ecosystems,” said Jason Link of the Northeast Fisheries Science Center lab in Woods Hole, Mass., who served as a guest editor of the issue and is a co-author of several of the 17 research articles.
"Other comparative ecosystem studies have been conducted, but most have involved applying a single statistical model to multiple systems or multiple models to one ecosystem. MENU is the first attempt to provide a comprehensive, coordinated and integrated view of a wide range of marine ecosystems.”
Researchers involved in MENU and in other comparative analyses found underlying patterns in the ecosystems that would not have been apparent had only one ecosystem been studied. For example, MENU results revealed that deeper eastern ocean boundary systems, like those off Alaska or in the eastern North Atlantic off Europe, are more strongly influenced by bottom-up mechanisms, known as forcing. These would include broad scale oceanographic systems like the Pacific Decadal Oscillation and the El Nino Southern Oscillation.
Shallower western boundary systems, mainly on continental shelves, like Georges Bank and other areas off the east coast of the U.S. and Canada, are more strongly influenced by top-down processes, such as fisheries exploitation. "Both top-down and bottom-up processes occur in all of these ecosystems, but being able to determine their relative importance is difficult.," Link said.
The researchers compared marine ecosystems in the northern hemisphere and mostly in high latitudes, ranging from the eastern Bering Sea and Gulf of Alaska in the North Pacific to Georges Bank and the Gulf of Maine, North Sea and the Adriatic Sea off Italy. Other ecosystems studied included the Gulf of St. Lawrence, Scotian Shelf, Newfoundland Shelf, Southern New England, Gulf of Finland, and the Baltic Sea. All of these ecosystems support commercially important fisheries.
Fisheries landings in the ecosystems studied appear to have shifted from groundfish to invertebrates, such as squid, shrimp and scallops. In many, the fish community has changed from one dominated by demersal or bottom-dwelling species to one dominated by pelagic or upper water column species. The researchers note that it is unclear if their findings are true of all marine ecosystems, or just those studied. One of the many questions raised by the comparative analyses is whether similar species in different ecosystems react to environmental conditions in similar ways, or whether the local ecosystems override global factors.
Fisheries production varies widely among ecosystems, and is affected by changing natural and human-induced factors such as climate, pollution and fishing effort. With so many factors involved, Link said scientists need to understand the relative importance of each factor in each ecosystem, something that is difficult to achive but important for an ecosystem approach to fisheries management and conservation.
“We do a lot of science, but rarely have the opportunity to pull it all together to understand the big picture, with basin-scale comparisons, so that we can start to understand processes within an ecosystem as well as between ecosystems,” Link said. “Since we cannot conduct experiments in large marine ecosystems, we used the comparative approach in MENU as a natural experiment to address a number of questions. Among these are what is fundamental to ecosystems in general, and what is unique to particular ecosystems?”
Scientists are already undertaking more integrated ecosystem assessments like MENU in the U.S. to build on decades of smaller scale, more focused studies on individual ecosystems. Comparative Analysis of Marine Ecosystem Organization, or CAMEO, is a partnership between NOAA’s Fisheries Service and the National Science Foundation to advance understanding of marine ecological systems using a comparative approach. CAMEO funded seven projects for 2008-2009 and is currently soliciting research proposals for 2009-2010.
Adapted from materials provided by NOAA Fisheries Northeast Fisheries Science Center.
Saturday, September 19, 2009
Live Birth - Key To Much Marine Life - Depends Upon Evolution Of Chromosomal Sex Determination
A new analysis of extinct sea creatures suggests that the transition from egg-laying to live-born young opened up evolutionary pathways that allowed these ancient species to adapt to and thrive in open oceans.
The evolutionary sleuthing is described this week in the journal Nature by scientists at Harvard University and the University of Reading who also report that the evolution of live-born young depended crucially on the advent of genes -- rather than incubation temperature -- as the primary determinant of offspring sex.
Having drawn this link in three lineages of extinct marine reptiles -- mosasaurs, sauropterygians, and ichthyosaurs -- the scientists say that genetic, or chromosomal, sex determination may have played a surprisingly strong role in adaptive radiations and the colonization of the world's oceans by a diverse array of species.
"Determining sex with genetic mechanisms allowed marine reptiles to give live birth, in the water, as opposed to laying eggs on a nesting beach," says Chris Organ, a research fellow in Harvard's Department of Organismic and Evolutionary Biology. "This freed these species from the need to move and nest on land. As a consequence extreme physical adaptations evolved in each group, such as the fluked tails, dorsal fins, and the wing-like limbs of ichthyosaurs."
Mosasaurs, sauropterygians, and ichthyosaurs invaded the Mesozoic seas between 251 million and 100 million years ago. All three groups of extinct marine reptiles breathed air, but evolved other adaptations to life in the open ocean, such as fin-shaped limbs, streamlined bodies, and changes in bone structure. Some evolved into enormous predators, such as porpoise-like ichthyosaurs that grew to more than 20 meters in length. Ichthyosaurs, and possibly mosasaurs, even evolved tail-first birth, an adaptation that helps modern whales and porpoises avoid drowning during birth.
"Losing the requirement of dry land during the life cycle of ichthyosaurs and other marine reptiles freed them to lead a completely aquatic existence, a shift that seems advantageous in light of the diversification that followed," says Daniel E. Janes, a research associate in Harvard's Department of Organismic and Evolutionary Biology.
Even though populations of most animals have males and females, the way sex is determined in offspring varies. Some animals rely primarily on sex chromosomes, as in humans where two X chromosomes make a female and an X and a Y chromosome make a male. Among living marine species, whales, porpoises, manatees, and sea snakes have chromosomal sex determination.
In sea turtles and saltwater crocodiles, on the other hand, the sex of offspring is generally determined by the temperature at which eggs incubate. These species are also bound to a semi-terrestrial existence because their gas-exchanging hard-shelled eggs must be deposited on land.
"No one has clearly understood how sex determination has co-evolved with live birth and egg laying," Organ says.
Organ, Janes, and colleagues show that evolution of live birth in a species depends on the prior evolution of genetic sex determination. Since the fossilized remains of pregnant mosasaurs, sauropterygians, and ichthyosaurs show that these species gave birth to live young, they must also have employed genetic sex determination, a point on which the fossil record is silent.
Organ and Janes' co-authors on the Nature paper are Andrew Meade and Mark Pagel of the University of Reading. Their work was funded by Harvard's Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology and by the National Institutes of Health.
Adapted from materials provided by Harvard University. Original article written by Steve Bradt, Harvard News Office.
Having drawn this link in three lineages of extinct marine reptiles -- mosasaurs, sauropterygians, and ichthyosaurs -- the scientists say that genetic, or chromosomal, sex determination may have played a surprisingly strong role in adaptive radiations and the colonization of the world's oceans by a diverse array of species.
"Determining sex with genetic mechanisms allowed marine reptiles to give live birth, in the water, as opposed to laying eggs on a nesting beach," says Chris Organ, a research fellow in Harvard's Department of Organismic and Evolutionary Biology. "This freed these species from the need to move and nest on land. As a consequence extreme physical adaptations evolved in each group, such as the fluked tails, dorsal fins, and the wing-like limbs of ichthyosaurs."
Mosasaurs, sauropterygians, and ichthyosaurs invaded the Mesozoic seas between 251 million and 100 million years ago. All three groups of extinct marine reptiles breathed air, but evolved other adaptations to life in the open ocean, such as fin-shaped limbs, streamlined bodies, and changes in bone structure. Some evolved into enormous predators, such as porpoise-like ichthyosaurs that grew to more than 20 meters in length. Ichthyosaurs, and possibly mosasaurs, even evolved tail-first birth, an adaptation that helps modern whales and porpoises avoid drowning during birth.
"Losing the requirement of dry land during the life cycle of ichthyosaurs and other marine reptiles freed them to lead a completely aquatic existence, a shift that seems advantageous in light of the diversification that followed," says Daniel E. Janes, a research associate in Harvard's Department of Organismic and Evolutionary Biology.
Even though populations of most animals have males and females, the way sex is determined in offspring varies. Some animals rely primarily on sex chromosomes, as in humans where two X chromosomes make a female and an X and a Y chromosome make a male. Among living marine species, whales, porpoises, manatees, and sea snakes have chromosomal sex determination.
In sea turtles and saltwater crocodiles, on the other hand, the sex of offspring is generally determined by the temperature at which eggs incubate. These species are also bound to a semi-terrestrial existence because their gas-exchanging hard-shelled eggs must be deposited on land.
"No one has clearly understood how sex determination has co-evolved with live birth and egg laying," Organ says.
Organ, Janes, and colleagues show that evolution of live birth in a species depends on the prior evolution of genetic sex determination. Since the fossilized remains of pregnant mosasaurs, sauropterygians, and ichthyosaurs show that these species gave birth to live young, they must also have employed genetic sex determination, a point on which the fossil record is silent.
Organ and Janes' co-authors on the Nature paper are Andrew Meade and Mark Pagel of the University of Reading. Their work was funded by Harvard's Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology and by the National Institutes of Health.
Adapted from materials provided by Harvard University. Original article written by Steve Bradt, Harvard News Office.
Wednesday, September 09, 2009
Climate Change Influences The Size Of Marine Organisms: Big Advantage For The Small
The ice is melting, the sea level is rising and species are conquering new habitats. The warming of the world climate has many consequences. Researchers now report that climate change influences the size of aquatic organisms.
For a long time scientists have observed the biological consequences of global climate change. One of the most famous symptoms is the shift of habitats from the equator further north or further south. More recent studies show that not only the habitats but also the size of organisms is affected.
Dr. Martin Daufresne of the HYAX Lake Ecosystem Laboratory in Aix-en-Provence, France, as well as Prof. Ulrich Sommer and Dr. Kathrin Lengfellner of the Leibniz-Institute of Marine Sciences (IFM-GEOMAR) in Kiel have shown that global warming leads to reduced body size of organisms in the ocean and in freshwater. Very different organisms showed this tendency: bacteria, plankton-algae, zooplankton and fishes in the North and Baltic Sea and in French rivers.
Three mechanisms seem to play a role in this process.
First: The proportion of smaller species grows.
Second: The proportion of smaller individuals grows within one species.
Third: The animals reach sexual maturity with smaller body size.
“This development affects the functioning of the whole eco-system: The body size is decisive for what animals can eat and by whom they are eaten. A shift to smaller species and individuals within the fish population could lead to a reduction of zooplankton because small fish will eat less fish and more zooplankton. This could pave the way fvor massive and unpleasant algal blooms. Furthermore, with smaller fish the economic value of fishery declines”, explains Prof. Sommer.
The bacteria, algae and zooplankton were examined in experiments of Baltic Sea plankton as part of the German Research Foundation-programme AQUASHIFT. The results about fish size are based on long term measurements in the North Sea, the Baltic Sea and in French Rivers.
Journal reference:
Daufresne et al. Global warming benefits the small in aquatic ecosystems. Proceedings of the National Academy of Sciences, 2009; DOI: 10.1073/pnas.0902080106
Adapted from materials provided by Leibniz Institute of Marine Sciences (IFM-GEOMAR).
Dr. Martin Daufresne of the HYAX Lake Ecosystem Laboratory in Aix-en-Provence, France, as well as Prof. Ulrich Sommer and Dr. Kathrin Lengfellner of the Leibniz-Institute of Marine Sciences (IFM-GEOMAR) in Kiel have shown that global warming leads to reduced body size of organisms in the ocean and in freshwater. Very different organisms showed this tendency: bacteria, plankton-algae, zooplankton and fishes in the North and Baltic Sea and in French rivers.
Three mechanisms seem to play a role in this process.
First: The proportion of smaller species grows.
Second: The proportion of smaller individuals grows within one species.
Third: The animals reach sexual maturity with smaller body size.
“This development affects the functioning of the whole eco-system: The body size is decisive for what animals can eat and by whom they are eaten. A shift to smaller species and individuals within the fish population could lead to a reduction of zooplankton because small fish will eat less fish and more zooplankton. This could pave the way fvor massive and unpleasant algal blooms. Furthermore, with smaller fish the economic value of fishery declines”, explains Prof. Sommer.
The bacteria, algae and zooplankton were examined in experiments of Baltic Sea plankton as part of the German Research Foundation-programme AQUASHIFT. The results about fish size are based on long term measurements in the North Sea, the Baltic Sea and in French Rivers.
Journal reference:
Daufresne et al. Global warming benefits the small in aquatic ecosystems. Proceedings of the National Academy of Sciences, 2009; DOI: 10.1073/pnas.0902080106
Adapted from materials provided by Leibniz Institute of Marine Sciences (IFM-GEOMAR).
Wednesday, June 17, 2009
Marine life at Pulau Perhentian (Malaysia) under threat from trash
Pulau Perhentian Besar and Kecil, the havens for marine life, are under threat environmentally due to poorly planned tourism development, ineffective sewage treatment and solid waste disposal.The state government is worried that this could lead to severe damage to coral reefs found in abundance surrounding both islands.State Commercial, Industry and Environment Committee chairman Toh Chin Yaw said the new chalets have compounded the problem as many of them did not have proper sewage and rubbish disposal systems."Some of these operators are taking the easy way out by diverting all types of wastes from their chalets direct into the sea," he said in an interview yesterday.Toh said during the peak season, mounds of garbage bags could also be seen around the islands, believed to have been left by these operators."They are blaming us for not centralising the sewage system and garbage collection without realising that it is too costly for the state government to do that.Just dumped: A photo showing bags of rubbish dumped onto floating rafts meant for tourists at Pulau Perhentian, Terengganu."We have commissioned a contractor to regularly collect the garbage from the islands to be disposed of on the mainland, but many of the operators are refusing to pay the maintenance fees and continued to indiscriminately throw their garbage into the sea," he added.Toh said the state government would build a sewage treatment plant on the islands if the operators were willing to pay the monthly maintenance fees.However, he doubted that they would do so as at present, they were also unwilling to share part of their revenues to be utilised for the pollution control efforts as advocated by the state government."We are intensifying our environmental awareness programme, besides encouraging operators to improve their waste facilities."We will also rope in the relevant authorities to educate these operators on the importance of protecting the eco-system at these islands," he added.Source: http://www.thestar.com.my/news/story.asp?file=/2009/6/15/nation/4120173&sec=nation
THE STAR Online: Marine life at Pulau Perhentian under threat from trash
Thursday, May 14, 2009
Climate change threatens millions who live off sea
Around 100 million people risk losing their homes and livelihoods unless drastic steps are taken to protect Southeast Asia's coral reefs, which could be wiped out in coming decades because of climate change, a report said Wednesday.The Coral Triangle — which spans Indonesia, the Philippines, Malaysia, Papua New Guinea, the Solomon Islands and East Timor — accounts for a third of the world's coral reefs and 35 percent of coral reef fish species.If carbon emissions are not cut by 25 percent to 40 percent by the year 2020, higher ocean temperatures could kill off vast marine ecosystems and half the fish in them, according to the World Wildlife Fund, which warned that 100 million people earning a living off the sea could be forced to leave inundated coastlines and find new jobs.The group, which presented its 220-page study at the World Ocean Conference, cited 300 published scientific studies and 20 climate change experts."Decisive action must be taken immediately, or a major crisis will develop," the report said."Hundreds of thousands of unique species, entire communities and societies will be in jeopardy," it said.Scientists have long warned that higher temperatures will melt polar ice and cause sea levels to rise, wiping out island communities and coastal ecosystems. Increasing carbon dioxide is also making oceans increasingly acidic, eroding sea shells, bleaching coral and killing other marine life.But many questions remain about oceans — which can also play an important part in absorbing carbon — partly because the technology to study them is relatively new."We are looking to promote better understanding of the role of the ocean in the climate system," said Mary M. Glackin, U.S. deputy undersecretary for oceans and atmosphere. "It's really a web of life. So you need to be concerned about the very smallest thing up to the very high predators.""The acidity that will be impacting some of those species could really have ripple-through effects," she added.Fish living in the coral reefs, mangroves and sea grass ecosystems in Southeast Asia generate $3 billion in annual income through commercial fishing, provide coastal protection from high waves and give food security to millions of the world's poorest families.In addition to climate change, marine ecosystems are being eroded by pollution, declining water quality, overfishing and destructive fishing techniques.Indonesia, the world's largest archipelago, said Wednesday it wasn't going to stand by and wait for disaster.It officially launched a new, protected marine park in the Coral Triangle with a unique and varied ecosystem that is considered to be especially resilient to rising sea temperatures.The park, an area about the size of the Netherlands, is a major migratory corridor and home to 14 whale species, as well as dolphins, dugongs, manta rays and sea turtles. It also has a high concentration of iridescent coral, fish, crustaceans, mollusks and plants."If well managed, this park has the capability to support sustainable fisheries and to ensure food security" for up to 2 million people in the region, said Minister of Marine Affairs and Fisheries Freddy Numberi.The five-day oceans' conference in Manado is aimed at shaping scientific debate about the role of oceans ahead of a U.N. climate change meeting in Copenhagen, Denmark, in December.That meeting will discuss a successor to the Kyoto Protocol, which expires in 2012. By GRACE WAKARY, Associated Press Writer Grace Wakary.
Tuesday, March 10, 2009
Acid oceans transform marine life
Ocean acidification driven by climate change is stripping away the protective shell of tiny yet vital organisms that absorb huge amounts of carbon pollution from the atmosphere, a new study has revealed.Since the start of the Industrial Revolution, the calcium carapace of microscopic animals called foraminifera living in the Southern Ocean have fallen in weight by a third, the study found.The amoeba-like organisms, about the size of a grain of sand, live in the surface waters of oceans around the world.They are an important part of the ecological chain and also provide a bulwark against global warming.They transform carbon dioxide (CO2) from the air into calcium-based shells. When they die, their carbon-rich shells sink to the ocean floor, effectively storing the atmospheric CO2 forever.Previous studies have shown that other marine animals, notably corals, are losing their ability to form exoskeletons from calcium.However, the potential causes for this are tangled, and include rising temperatures and nutrient runoff from coastal agriculture as well as acidification.This is the first study to look specifically at acidification and pin it to greenhouse-gas pollution, which is driven especially by the invisible product of burning oil, gas and coal."It is the invasion of anthropogenic (man-made) CO2 that is causing this particular source of acidification," said co-author William Howard of the Antarctic Climate and Ecosystems Cooperative Research Center in Hobart, Tasmania.Howard's team collected shells of one foraminifera species, Globigerina bulloides, as they drifted toward the sea floor, and compared them to older specimens that had sunk several hundred years earlier.The newer shells had 30-to-35 percent less mass, they reported in the online edition of the journal Nature Geoscience."If forams and other shell makers are not making shells, that might change the transfer of carbon from the surface ocean into the deep ocean," said Howard."It changes the efficiency of the biological pump, and would tend to lessen the degree to which the ocean takes up carbon. That's a feedback that we have to be concerned about," he said in a phone interview.Only in the last five years have scientists become aware of the extent of ocean acidification and its potential to disrupt Earth's carbon cycle, which balances the absorption and release of CO2 into the atmospshere."The problem with this impact is that it is so persistent and so long-lived, unlike other pollution carbons. We will have a harder time turning this impact around," Howard said.The geo-chemical mechanisms that buffer acidification work very slowly, he explained."It is like taking an antacid tablet for an upset stomach and then having to wait hundreds -- or thousands -- of years for it to work."If the loss of shell mass threatens the survival of the amoeba-like creatures, it could also disrupt a food chain reaching from the plankton they eat, all the way up to large sea mammal such as whales. "We don't know yet what those impacts might be," Howard said.
Sunday, March 08, 2009
New Light Shed On Marine Luminescence
The phenomenon of light emission by living organisms, bioluminescence, is quite common, especially in marine species. It is known that light is generated by chemical reactions in which oxygen molecules play an important part.
In the animal world, these chemical reactions take place in special luminescent cells called photocytes. These are aggregated into complex light organs, in which the intensity of light is regulated by nerve impulses, and in which light can be modulated with the help of reflectors, lenses and filters. By these means, organisms can adjust the wavelength, diffusion and intensity of light according to need. But the exact mechanisms behind these processes remain shrouded in mystery.
Jenny Krönström, a researcher at the Department of Zoology of the University of Gothenburg has put another piece of the jigsaw puzzle in place by investigating the light organs of marine jellyfish, crustaceans and fish. In her thesis she reveals that krill, the luminescent crustacean, is equipped with special muscles that regulate light intensity through contraction and relaxation.
Nitric oxide is also thought to play an important role in the bioluminescence of krill. It is produced in the small capillary vessels that keep the krill's photocytes supplied with oxygen, as well as in special closure muscles, sphincters, that are located at the point where these capillaries distribute blood to the photocytes. Experiments with agents that make the sphincters contract or relax show that when the sphincters relax, the krill begins to luminesce, presumably because of the increased flow of oxygenated blood to the photocytes.
As bioluminescence has developed independently at several different points in evolution, different species have developed different methods of regulating and emitting light. Jenny Krönström's research demonstrates that nitric oxide also has different effects in different species. In the remarkable deep sea Silver Hatchetfish (Argyropelecus olfersii) nitric oxide inhibits the light reaction, whilst in the Plain Midshipman fish (Porichthys notatus) it has an opposite, stimulating effect.
Biological light is not only useful to the organism itself as a biological torch, camouflage or as a means of communication; the substances that are involved in the chemical luminescent reaction have also shown themselves to be useful in modern molecular biology, in which the discovery of green fluorescent protein, which produces green light in jellyfish, led to the Nobel Prize in Chemistry as recently as 2008.
The thesis "Control of bioluminescence: Operating the light switch in photophores from marine animals" is to be publicly defended on February 20th 2009.
Adapted from materials provided by University of Gothenburg.
Jenny Krönström, a researcher at the Department of Zoology of the University of Gothenburg has put another piece of the jigsaw puzzle in place by investigating the light organs of marine jellyfish, crustaceans and fish. In her thesis she reveals that krill, the luminescent crustacean, is equipped with special muscles that regulate light intensity through contraction and relaxation.
Nitric oxide is also thought to play an important role in the bioluminescence of krill. It is produced in the small capillary vessels that keep the krill's photocytes supplied with oxygen, as well as in special closure muscles, sphincters, that are located at the point where these capillaries distribute blood to the photocytes. Experiments with agents that make the sphincters contract or relax show that when the sphincters relax, the krill begins to luminesce, presumably because of the increased flow of oxygenated blood to the photocytes.
As bioluminescence has developed independently at several different points in evolution, different species have developed different methods of regulating and emitting light. Jenny Krönström's research demonstrates that nitric oxide also has different effects in different species. In the remarkable deep sea Silver Hatchetfish (Argyropelecus olfersii) nitric oxide inhibits the light reaction, whilst in the Plain Midshipman fish (Porichthys notatus) it has an opposite, stimulating effect.
Biological light is not only useful to the organism itself as a biological torch, camouflage or as a means of communication; the substances that are involved in the chemical luminescent reaction have also shown themselves to be useful in modern molecular biology, in which the discovery of green fluorescent protein, which produces green light in jellyfish, led to the Nobel Prize in Chemistry as recently as 2008.
The thesis "Control of bioluminescence: Operating the light switch in photophores from marine animals" is to be publicly defended on February 20th 2009.
Adapted from materials provided by University of Gothenburg.
Friday, February 27, 2009
Antibiotic Resistance: Rising Concern In Marine Ecosystems
A team of scientists, speaking February 13 at the annual meeting of the American Association for the Advancement of Science, called for new awareness of the potential for antibiotic-resistant illnesses from the marine environment, and pointed to the marine realm as a source for possible cures of those threats
The group stated that newly completed studies of ocean beach users point to an increasing risk of staph infections, and that current treatments for seafood poisoning may be less effective due to higher than expected antibiotic resistance. The group also asserts that new research has identified sponge and coral-derived chemicals with the potential for breaking down antibiotic resistant compounds and that could lead to new personalized medical treatments.
"While the marine environment can indeed be hostile to humans, it may also provide new resources to help reduce our risks from illnesses such as those caused by water borne staph or seafood poisoning," stated Paul Sandifer, Ph.D., former member of the U.S. Commission on Ocean Policy, chief scientist of NOAA's Oceans and Human Health Initiative, and co-organizer of the symposium.
Carolyn Sotka, also with the NOAA Oceans and Human Health Initiative and lead organizer of the session, stated "It is critically important that we continue research on the complex interactions between the condition of our oceans and human health. Without doubt, this research will develop new understandings of ocean health risks and perhaps more importantly crucial discoveries that will lead to new solutions to looming public health problems."
Coral, Sponges Point To Personalized Medicine Potential
"We've found significant new tools to fight the antibiotic resistance war," says NOAA research scientist Peter Moeller, Ph.D., in describing the identification of new compounds derived from a sea sponge and corals.
"The first hit originates with new compounds that remove the shield bacteria utilize to protect themselves from antibiotics. The second hit is the discovery of novel antibiotics derived from marine organisms such as corals, sponges and marine microbes that fight even some of the worst infectious bacterial strains. With the variety of chemicals we find in the sea and their highly specific activities, medicines in the near future can be customized to individuals' needs, rather than relying on broad spectrum antibiotics."
The research team, a collaboration between scientists at NOAA's Hollings Marine Laboratory in Charleston, S.C., the Medical University of South Carolina and researchers at North Carolina State University in Raleigh, N.C., noticed a sponge that seemed to thrive despite being located in the midst of a dying coral reef. After extraction, testing showed that one of the isolated chemicals, algeliferin, breaks down a biofilm barrier that bacteria use to protect themselves from threats including antibiotics. The same chemical can also disrupt or inhibit formation of biofilm on a variety of bacteria previously resistant to antibiotics which could lead to both palliative and curative response treatment depending on the problem being addressed.
"This could lead to a new class of helper drugs and result in a rebirth for antibiotics no longer thought effective," notes Moeller. "Its potential application to prevent biofilm build-up in stents, intravenous lines and other medical uses is incredible."
The compound is currently being tested for a variety of medical uses and has gone through a second round of sophisticated toxicity screening and thus far shows no toxic effects.
Staph: A Beach Going Concern
Research, funded by multiple agencies and conducted by the University of Miami's Rosenstiel School of Marine and Atmospheric Sciences and the Leonard M. Miller School of Medicine, found that swimmers using public ocean beaches increase their risk for exposure to staph organisms, and they may increase their risk for potential staph infections once they enter the water.
"Our study found that if you swim in subtropical marine waters, you have a significant chance , approximately 37 percent, of being exposed to staph — either yours or possibly that from someone else in the water with you," said Dr. Lisa Plano, a pediatrician and microbiologist with the Miller School of Medicine. Plano collaborated in the first large epidemiologic survey of beach users in recreational marine waters without a sewage source of pollution. "This exposure might lead to colonization or infection by water-borne bacteria which are shed from every person who enters the water. People who have open wounds or are immune-compromised are at greatest risk of infection."
The Miami research team does not advise avoiding beaches, but recommends that beach-goers take precautions to reduce risk by showering thoroughly before entering the water and after getting out. They also point out that while antibiotic resistant staph, commonly known as MRSA, has been increasingly found in diverse environments, including the marine environment, less than three percent of staph isolated from beach waters in their study was of the potentially virulent MRSA variety. More research is needed to understand how long staph (including MRSA) can live in coastal waters, and human uptake and infection rates associated with beach exposures.
Antibiotic Resistance in Seafood-borne Pathogens Increasing
Researchers at the Bigelow Laboratory for Ocean Science in West Boothbay Harbor, Maine, report that the frequency of antibiotic resistance in vibrio bacteria was significantly higher than expected. These findings suggest that the current treatment of vibirio infections should be re-examined, since these microbes are the leading cause of seafood-borne illness and death in the United States. The severity of these infections makes antibiotic resistance in vibrios a critical public health concern.
Naturally-occurring resistance to antibiotics among Vibrios may undermine the effectiveness of antibiotic treatment, but as yet this has not been extensively studied. Furthermore, antibiotics and other toxicants discharged into the waste stream by humans may increase the frequency of antibiotic-resistant Vibrio strains in contaminated coastal environments.
"We found resistance to all major classes of antibiotics routinely used to treat Vibrio infections, including aminoglycosides, tetracyclines, and cephalosporins," stated Bigelow's Ramunas Stepanauskas, Ph.D. "In contrast, we found that Vibrios were highly susceptible to carbapenems and new-generation fluoroquinolones, such as Imipenem and Ciprofloxacin. This information may be used to design better strategies to treat Vibrio infections."
Adapted from materials provided by National Oceanic And Atmospheric Administration, via EurekAlert!, a service of AAAS.
"While the marine environment can indeed be hostile to humans, it may also provide new resources to help reduce our risks from illnesses such as those caused by water borne staph or seafood poisoning," stated Paul Sandifer, Ph.D., former member of the U.S. Commission on Ocean Policy, chief scientist of NOAA's Oceans and Human Health Initiative, and co-organizer of the symposium.
Carolyn Sotka, also with the NOAA Oceans and Human Health Initiative and lead organizer of the session, stated "It is critically important that we continue research on the complex interactions between the condition of our oceans and human health. Without doubt, this research will develop new understandings of ocean health risks and perhaps more importantly crucial discoveries that will lead to new solutions to looming public health problems."
Coral, Sponges Point To Personalized Medicine Potential
"We've found significant new tools to fight the antibiotic resistance war," says NOAA research scientist Peter Moeller, Ph.D., in describing the identification of new compounds derived from a sea sponge and corals.
"The first hit originates with new compounds that remove the shield bacteria utilize to protect themselves from antibiotics. The second hit is the discovery of novel antibiotics derived from marine organisms such as corals, sponges and marine microbes that fight even some of the worst infectious bacterial strains. With the variety of chemicals we find in the sea and their highly specific activities, medicines in the near future can be customized to individuals' needs, rather than relying on broad spectrum antibiotics."
The research team, a collaboration between scientists at NOAA's Hollings Marine Laboratory in Charleston, S.C., the Medical University of South Carolina and researchers at North Carolina State University in Raleigh, N.C., noticed a sponge that seemed to thrive despite being located in the midst of a dying coral reef. After extraction, testing showed that one of the isolated chemicals, algeliferin, breaks down a biofilm barrier that bacteria use to protect themselves from threats including antibiotics. The same chemical can also disrupt or inhibit formation of biofilm on a variety of bacteria previously resistant to antibiotics which could lead to both palliative and curative response treatment depending on the problem being addressed.
"This could lead to a new class of helper drugs and result in a rebirth for antibiotics no longer thought effective," notes Moeller. "Its potential application to prevent biofilm build-up in stents, intravenous lines and other medical uses is incredible."
The compound is currently being tested for a variety of medical uses and has gone through a second round of sophisticated toxicity screening and thus far shows no toxic effects.
Staph: A Beach Going Concern
Research, funded by multiple agencies and conducted by the University of Miami's Rosenstiel School of Marine and Atmospheric Sciences and the Leonard M. Miller School of Medicine, found that swimmers using public ocean beaches increase their risk for exposure to staph organisms, and they may increase their risk for potential staph infections once they enter the water.
"Our study found that if you swim in subtropical marine waters, you have a significant chance , approximately 37 percent, of being exposed to staph — either yours or possibly that from someone else in the water with you," said Dr. Lisa Plano, a pediatrician and microbiologist with the Miller School of Medicine. Plano collaborated in the first large epidemiologic survey of beach users in recreational marine waters without a sewage source of pollution. "This exposure might lead to colonization or infection by water-borne bacteria which are shed from every person who enters the water. People who have open wounds or are immune-compromised are at greatest risk of infection."
The Miami research team does not advise avoiding beaches, but recommends that beach-goers take precautions to reduce risk by showering thoroughly before entering the water and after getting out. They also point out that while antibiotic resistant staph, commonly known as MRSA, has been increasingly found in diverse environments, including the marine environment, less than three percent of staph isolated from beach waters in their study was of the potentially virulent MRSA variety. More research is needed to understand how long staph (including MRSA) can live in coastal waters, and human uptake and infection rates associated with beach exposures.
Antibiotic Resistance in Seafood-borne Pathogens Increasing
Researchers at the Bigelow Laboratory for Ocean Science in West Boothbay Harbor, Maine, report that the frequency of antibiotic resistance in vibrio bacteria was significantly higher than expected. These findings suggest that the current treatment of vibirio infections should be re-examined, since these microbes are the leading cause of seafood-borne illness and death in the United States. The severity of these infections makes antibiotic resistance in vibrios a critical public health concern.
Naturally-occurring resistance to antibiotics among Vibrios may undermine the effectiveness of antibiotic treatment, but as yet this has not been extensively studied. Furthermore, antibiotics and other toxicants discharged into the waste stream by humans may increase the frequency of antibiotic-resistant Vibrio strains in contaminated coastal environments.
"We found resistance to all major classes of antibiotics routinely used to treat Vibrio infections, including aminoglycosides, tetracyclines, and cephalosporins," stated Bigelow's Ramunas Stepanauskas, Ph.D. "In contrast, we found that Vibrios were highly susceptible to carbapenems and new-generation fluoroquinolones, such as Imipenem and Ciprofloxacin. This information may be used to design better strategies to treat Vibrio infections."
Adapted from materials provided by National Oceanic And Atmospheric Administration, via EurekAlert!, a service of AAAS.
Wednesday, December 03, 2008
Antarctica Has More Species Than Galapagos, First Comprehensive Inventory Of Antarctic Life Shows
The first comprehensive “inventory” of sea and land animals around a group of Antarctic islands reveals a region that is rich in biodiversity and has more species than the Galapagos. The study provides an important benchmark to monitor how they will respond to future environmental change.
Reporting this week in the Journal of Biogeography, the team from British Antarctic Survey and University of Hamburg, describe how they combed the land, sea and shores of the South Orkney Islands, near the tip of the Antarctic Peninsula, using scuba divers and trawled nets to catch creatures as deep as 1500 metres.
Animals recorded were then checked with a century of literature and modern databases and the team concludes there are over 1200 known marine and land species. These include sea urchins, free-swimming worms, crustaceans and molluscs, mites and birds. Five were new to science.
Lead author Dr David Barnes from British Antarctic Survey (BAS) says: “This is the first time anybody has done an inventory like this in the polar regions. It’s part of the Census of Marine Life (COML) – an international effort to assess and explain the diversity and distribution of marine life in the world’s oceans. If we are to understand how these animals will respond to future change, a starting point like this is really important.”
Author Stefanie Kaiser from University of Hamburg says: “We never knew there were so many different species on and around these islands. This abundance of life was completely unexpected for a location in the polar regions, previously perceived to be poor in biodiversity.”
The research team, consisting of 23 scientists from five research institutes, spent seven weeks on the BAS Royal Research Ship James Clark Ross in 2006.
Adapted from materials provided by British Antarctic Survey (BAS).
Animals recorded were then checked with a century of literature and modern databases and the team concludes there are over 1200 known marine and land species. These include sea urchins, free-swimming worms, crustaceans and molluscs, mites and birds. Five were new to science.
Lead author Dr David Barnes from British Antarctic Survey (BAS) says: “This is the first time anybody has done an inventory like this in the polar regions. It’s part of the Census of Marine Life (COML) – an international effort to assess and explain the diversity and distribution of marine life in the world’s oceans. If we are to understand how these animals will respond to future change, a starting point like this is really important.”
Author Stefanie Kaiser from University of Hamburg says: “We never knew there were so many different species on and around these islands. This abundance of life was completely unexpected for a location in the polar regions, previously perceived to be poor in biodiversity.”
The research team, consisting of 23 scientists from five research institutes, spent seven weeks on the BAS Royal Research Ship James Clark Ross in 2006.
Adapted from materials provided by British Antarctic Survey (BAS).
Adopted from Science Daily
Monday, November 10, 2008
Sea census leads to discoveries of marine wonders
A city of brittle stars off the coast of New Zealand, an Antarctic expressway where octopuses ride along in a flow of extra salty water and a carpet of tiny crustaceans on the Gulf of Mexico sea floor are among the wonders discovered by researchers compiling a massive census of marine life."We are still making discoveries," but researchers also are busy assembling data already collected into the big picture of life in the oceans, senior scientist Ron O'Dor said.The fourth update of the census was released Sunday ahead of a meeting of hundreds of researchers that begins Tuesday in Valencia, Spain. More than 2,000 scientists from 82 nations are taking part in the project, which is to be completed in 2010.A discovery that delights O'Dor is that many deep-ocean octopuses share an Antarctic origin. As the Antarctic got colder, ice increased and octopuses were forced into deeper water, he said in a telephone interview.Salt and oxygen are concentrated in the deeper waters, he said. This dense water then flows out, carrying along the octopuses that have adapted to the new conditions, enabling them to spread to deep waters around the world.Deep-water octopuses worldwide, he pointed out, lack the ink sack that allows their shallow-water cousins to shoot out a camouflage screen.After all, if they live where it is dark, ink is unnecessary, said O'Dor, a Canadian member of the research team.Patricia Miloslavich, a senior scientist from Venezuela, is pleased with newly discovered mollusks, from snails to cuttlefish to squids.Once the census is complete, the plan is to publish three books: a popular survey of sea life, a second book with chapters for each working group and a third focusing on biodiversity.O'Dor said also researchers are working with the online scientific journal PLoS ONE, which is open to anyone and thus would make the results readily available.Scientists at this week's sessions will hear about the discovery of what the researchers call a brittle star city off the coast of New Zealand.The brittle stars, animals with five arms, have colonized the peak of a seamount — an underwater mountain — where the current flows past at about 2.5 miles per hour. The current delivers such an ample food supply that thousands of stars can capture food simply by raising their arms.Researchers found a carpet of small crustaceans inhabiting the head of the Mississippi Canyon in the Gulf of Mexico. There are as many as 12,000 of these small crustaceans per square yard.Among the other findings being reported at the meeting:_The mid-Atlantic ridge half way between America and Europe is home to hundreds of species rare or unknown elsewhere._The ridge includes the world's deepest known active hot vent, more than 13,300 feet (4,100 meters) deep and populated by anemones, worms and shrimp._Reefs deep in the Black Sea are made of bacterial mats using methane as an energy source. The bacteria form chimneys up to 13 feet (4 meters) high._The deepest comb jellyfish ever found was discovered at a depth of 23,455 feet (7,217 meters) in the Ryukyu Trench near Japan. The discovery raises questions about the availability of food resources at such depths, which had not been thought capable of supporting predators like this one. _The White Shark Cafe. Satellite tagging discovers that white sharks travel long distances each winter to concentrate in the Pacific for up to six months. While there, both males and females make frequent, repetitive dives to depths of 975 feet (300 meters), which researchers theorize may be significant in either feeding or reproduction.
Wednesday, July 09, 2008
Census Of Marine Life Lists 122,500 Known Species, Over Halfway To Complete Inventory By Oct. 2010
Census of Marine Life-affiliated scientists consolidating world databases of ocean organisms have demoted to alias status almost one-third of all names culled from 34 regional and highly specialized inventories.
The new World Register of Marine Species contains about 122,500 validated marine species names (experts having recognized and tidied up some 56,400 aliases -- 32% of all names reviewed). It also contains some 5,600 images, hyperlinks to taxonomic literature and other information.
Marking the World Register's official inauguration, some 55 researchers from 17 countries met in Belgium to plan its completion by 2010. Leading WoRMS experts independently estimate that about 230,000 marine species are known to science. They also believe there are three times as many unknown (unnamed) marine species as known, for a grand total on Earth that could surpass 1 million.
"Convincing warnings about declining fish and other marine species must rest on a valid census," says Dr. Mark Costello of the University of Auckland, co-founder of WoRMS and a senior Census of Marine Life official. "This project will improve information vital to researchers investigating fisheries, invasive species, threatened species and marine ecosystem functioning, as well as to educators. It will eliminate the misinterpretation of names, confusion over Latin spellings, redundancies and a host of other problems that sow confusion and slow scientific progress."
Some species, such as those reclassified in years past based on new information, were shown to have a handful of names or more.
In such cases, the oldest name trumps later ones to become the valid name (though all aliases are noted to help researchers interpret centuries of scientific literature).
Popularly called Breadcrumb Sponge, Halichondria panicea is the marine world's reigning champion of Latin aliases, with 56 synonyms appearing in taxonomic literature since its first description in 1766. Of no fixed address, it's known to frequent floats, pilings, and the underside of rocks, smells like exploded gunpowder and takes on many appearances (as shown in photos). It is also known as (AKA): Alcyonium manusdiaboli (1794), Spongia compacta (1806), Halichondria albescens (1818), Seriatula seriata (1826), Hymeniacidon brettii (1866), Pellina bibula (1870), Amorphina appendiculata (1875), Isodictya crassa (1882), Microciona tumulosa (1882), Menanetia minchini (1896), Trachyopsilla glaberrima (1931) and 44 other names.
No researcher's work is spared -- not even Carl Linnaeus, who in the 1750s overcame an international scientific Tower of Babel when it came to naming species. He instituted the two-word Latin name, starting with the (capitalized) genus, followed by a (lowercase) specific epithet, a system used ever since. Thanks to his method of binominal nomenclature, what is dubbed a bulot in French fish markets, whelk in New England, buccin in Canada, and the Wellhornschnecke of the North Sea, is known universally to scientists as Buccinum undatum.
However, over time it emerged that Linnaeus assigned four names to the same species of sperm whale, a mistake caught years ago but which still appears in world literature and databases. The World Register will clarify for all time the valid name for that whale and all other marine species for future researchers, census takers and educators alike.
Says Philippe Bouchet, a Census scientist involved in WoRMS: "Describing species without a universal register in place is like setting up a library without an index catalog."
Discovery outstrips description capacity
Census of Marine Life and other explorers are finding unknown species at a rate much faster than the capacity to describe them due to a shortage of experts. Dr. Bouchet calculates that 3,800 taxonomists enter at least 1,400 new marine species into the literature every year. At this rate, the process of discovering, verifying, describing and naming all remaining unknown marine species would take over five centuries.
The global scale cooperation underway by the Census and the World Register is a prerequisite for the more time and cost-efficient discovery and recording of ocean-dwelling species. So too are new technologies for sampling, image capture, data management, genetic analyses (e.g. DNA barcodes), new training programs for taxonomists, and online initiatives such as ZooBank, which can assign "official" permanent registration identifications to new animal species.
Hosted by the Flanders Marine Institute, Belgium, the World Register has received early funding from several sources, including the EU's MarBEF (Marine Biodiversity and Ecosystem Functioning) research network and PESI (Pan-European Species-Directories Infrastructures) project, the European Register of Marine Species, Species2000 Europa, CoML's International Census of Marine Microbes project, the Richard Lounsbery Foundation, and the Global Biodiversity Information Facility.
And it will serve as the taxonomic backbone of another funder -- the Ocean Biogeographic Information System (OBIS), the Census of Marine Life's portal to vast information on species, including their global distribution and other data, adds Dr. Costello, founding chair of OBIS.
The World Register will also contribute to several related global biodiversity enterprises, including the Encyclopedia of Life (creating a webpage for every species), and Species2000 (assembling a list of valid names for the 1.8 million or so known animals, plants, and fungi, both marine and terrestrial).
"Modern technologies allow unprecedented global collaboration to consolidate, validate and advance more than 250 years of research into the diverse species that live beneath the waves," says Dr. Edward Vanden Berghe, who heads OBIS at Rutgers University, New Jersey, and who initiated the World Register while working at the Flanders Marine Institute. "The World Register of Marine Species and the Ocean Biogeographic Information System will be major Census legacies."
How many species in the sea?
The Belgium meeting affirmed that the World Register should surpass 200,000 valid names by the end of 2008 and will offer the first complete listing of the estimated 230,000+ marine species known to science when the First Census of Marine Life (CoML) is released in October 2010.
"Decisions about the last few thousand species to be included could be difficult, as some descriptions are inadequate or the specimens missing," noted CoML Chief Scientist Ron O'Dor. "Experts may disagree on the scientific validity of an entry when evidence is contentious or scant."
The database has yet to reflect massive discovery efforts underway by CoML collaborators. Preliminary CoML estimates show many thousands of suspected new marine life species have been discovered in the first eight years of explorations, 110 of which have completed the formal description process.
The taxonomic analysis and description process means that "newly discovered" species often take years to appear in publications. The process involves exhaustive comparison, documentation, peer-review, publication, and depositing specimens in museum collections for others to access.
The Census is the largest-ever global marine biology research project, uniting researchers from more than 80 nations with the goal of assessing and explaining the diversity, distribution and abundance of ocean life -- past, present and future.
Started in 2000, some 17 projects (including 14 conducting field research) examining all aspects of sea life the world over are beginning to shift from data collection to analysis as the first Census moves towards a conclusion and synthesis report in 2010 -- an unprecedented baseline of information about ocean biodiversity in a changing environment.
In isolated parts of the world, such as the deep-sea, the tropics, and the Southern Ocean swirling around Antarctica, discovery of previously undescribed species can exceed 80% of specimens captured, especially for smaller animals like crustaceans, worms and molluscs. Census plankton project leader Ann Bucklin predicts her collaborators will at least double the number of known zooplankton species in the world, which in 2008 consisted of 7,000 species in 15 different phyla.
"Discovering a species never known to science before is one of the great prizes of marine research," says Ian Poiner, Australia-based chair of CoML's Scientific Steering Committee. "The accomplishment earns the researcher the hard-earned right to bestow the species with a name.
"For years to come, as new species discoveries are validated and enter the literature, some individual researchers could earn that right hundreds of times over -- and we look forward to seeing thousands of new species identified through the Census eventually fed to the World Register."
"What may appear a simple task on the surface is in fact two-fold: the names of every known species have first to be validated, and the register must also simultaneously try to keep pace with new discoveries," says WoRMS data manager Ward Appeltans of the Flanders Marine Institute (VLIZ), noting that one expert representing each taxonomic group is assigned to control the quality of the databank's content.
"The fact that every year scientists still find more than 100 new marine fish species in the sea is astonishing," he adds. "While we are looking up to search for life on Mars, there is still so much beauty to discover at our feet."
Adapted from materials provided by Census of Marine Life.
Marking the World Register's official inauguration, some 55 researchers from 17 countries met in Belgium to plan its completion by 2010. Leading WoRMS experts independently estimate that about 230,000 marine species are known to science. They also believe there are three times as many unknown (unnamed) marine species as known, for a grand total on Earth that could surpass 1 million.
"Convincing warnings about declining fish and other marine species must rest on a valid census," says Dr. Mark Costello of the University of Auckland, co-founder of WoRMS and a senior Census of Marine Life official. "This project will improve information vital to researchers investigating fisheries, invasive species, threatened species and marine ecosystem functioning, as well as to educators. It will eliminate the misinterpretation of names, confusion over Latin spellings, redundancies and a host of other problems that sow confusion and slow scientific progress."
Some species, such as those reclassified in years past based on new information, were shown to have a handful of names or more.
In such cases, the oldest name trumps later ones to become the valid name (though all aliases are noted to help researchers interpret centuries of scientific literature).
Popularly called Breadcrumb Sponge, Halichondria panicea is the marine world's reigning champion of Latin aliases, with 56 synonyms appearing in taxonomic literature since its first description in 1766. Of no fixed address, it's known to frequent floats, pilings, and the underside of rocks, smells like exploded gunpowder and takes on many appearances (as shown in photos). It is also known as (AKA): Alcyonium manusdiaboli (1794), Spongia compacta (1806), Halichondria albescens (1818), Seriatula seriata (1826), Hymeniacidon brettii (1866), Pellina bibula (1870), Amorphina appendiculata (1875), Isodictya crassa (1882), Microciona tumulosa (1882), Menanetia minchini (1896), Trachyopsilla glaberrima (1931) and 44 other names.
No researcher's work is spared -- not even Carl Linnaeus, who in the 1750s overcame an international scientific Tower of Babel when it came to naming species. He instituted the two-word Latin name, starting with the (capitalized) genus, followed by a (lowercase) specific epithet, a system used ever since. Thanks to his method of binominal nomenclature, what is dubbed a bulot in French fish markets, whelk in New England, buccin in Canada, and the Wellhornschnecke of the North Sea, is known universally to scientists as Buccinum undatum.
However, over time it emerged that Linnaeus assigned four names to the same species of sperm whale, a mistake caught years ago but which still appears in world literature and databases. The World Register will clarify for all time the valid name for that whale and all other marine species for future researchers, census takers and educators alike.
Says Philippe Bouchet, a Census scientist involved in WoRMS: "Describing species without a universal register in place is like setting up a library without an index catalog."
Discovery outstrips description capacity
Census of Marine Life and other explorers are finding unknown species at a rate much faster than the capacity to describe them due to a shortage of experts. Dr. Bouchet calculates that 3,800 taxonomists enter at least 1,400 new marine species into the literature every year. At this rate, the process of discovering, verifying, describing and naming all remaining unknown marine species would take over five centuries.
The global scale cooperation underway by the Census and the World Register is a prerequisite for the more time and cost-efficient discovery and recording of ocean-dwelling species. So too are new technologies for sampling, image capture, data management, genetic analyses (e.g. DNA barcodes), new training programs for taxonomists, and online initiatives such as ZooBank, which can assign "official" permanent registration identifications to new animal species.
Hosted by the Flanders Marine Institute, Belgium, the World Register has received early funding from several sources, including the EU's MarBEF (Marine Biodiversity and Ecosystem Functioning) research network and PESI (Pan-European Species-Directories Infrastructures) project, the European Register of Marine Species, Species2000 Europa, CoML's International Census of Marine Microbes project, the Richard Lounsbery Foundation, and the Global Biodiversity Information Facility.
And it will serve as the taxonomic backbone of another funder -- the Ocean Biogeographic Information System (OBIS), the Census of Marine Life's portal to vast information on species, including their global distribution and other data, adds Dr. Costello, founding chair of OBIS.
The World Register will also contribute to several related global biodiversity enterprises, including the Encyclopedia of Life (creating a webpage for every species), and Species2000 (assembling a list of valid names for the 1.8 million or so known animals, plants, and fungi, both marine and terrestrial).
"Modern technologies allow unprecedented global collaboration to consolidate, validate and advance more than 250 years of research into the diverse species that live beneath the waves," says Dr. Edward Vanden Berghe, who heads OBIS at Rutgers University, New Jersey, and who initiated the World Register while working at the Flanders Marine Institute. "The World Register of Marine Species and the Ocean Biogeographic Information System will be major Census legacies."
How many species in the sea?
The Belgium meeting affirmed that the World Register should surpass 200,000 valid names by the end of 2008 and will offer the first complete listing of the estimated 230,000+ marine species known to science when the First Census of Marine Life (CoML) is released in October 2010.
"Decisions about the last few thousand species to be included could be difficult, as some descriptions are inadequate or the specimens missing," noted CoML Chief Scientist Ron O'Dor. "Experts may disagree on the scientific validity of an entry when evidence is contentious or scant."
The database has yet to reflect massive discovery efforts underway by CoML collaborators. Preliminary CoML estimates show many thousands of suspected new marine life species have been discovered in the first eight years of explorations, 110 of which have completed the formal description process.
The taxonomic analysis and description process means that "newly discovered" species often take years to appear in publications. The process involves exhaustive comparison, documentation, peer-review, publication, and depositing specimens in museum collections for others to access.
The Census is the largest-ever global marine biology research project, uniting researchers from more than 80 nations with the goal of assessing and explaining the diversity, distribution and abundance of ocean life -- past, present and future.
Started in 2000, some 17 projects (including 14 conducting field research) examining all aspects of sea life the world over are beginning to shift from data collection to analysis as the first Census moves towards a conclusion and synthesis report in 2010 -- an unprecedented baseline of information about ocean biodiversity in a changing environment.
In isolated parts of the world, such as the deep-sea, the tropics, and the Southern Ocean swirling around Antarctica, discovery of previously undescribed species can exceed 80% of specimens captured, especially for smaller animals like crustaceans, worms and molluscs. Census plankton project leader Ann Bucklin predicts her collaborators will at least double the number of known zooplankton species in the world, which in 2008 consisted of 7,000 species in 15 different phyla.
"Discovering a species never known to science before is one of the great prizes of marine research," says Ian Poiner, Australia-based chair of CoML's Scientific Steering Committee. "The accomplishment earns the researcher the hard-earned right to bestow the species with a name.
"For years to come, as new species discoveries are validated and enter the literature, some individual researchers could earn that right hundreds of times over -- and we look forward to seeing thousands of new species identified through the Census eventually fed to the World Register."
"What may appear a simple task on the surface is in fact two-fold: the names of every known species have first to be validated, and the register must also simultaneously try to keep pace with new discoveries," says WoRMS data manager Ward Appeltans of the Flanders Marine Institute (VLIZ), noting that one expert representing each taxonomic group is assigned to control the quality of the databank's content.
"The fact that every year scientists still find more than 100 new marine fish species in the sea is astonishing," he adds. "While we are looking up to search for life on Mars, there is still so much beauty to discover at our feet."
Adapted from materials provided by Census of Marine Life.
Thursday, January 24, 2008
Lungfish a breed apart
QUEENSLAND lungfish may be regarded as unusual and totally protected, but Gordon Hides has about 7000 of them."We have worked out how to breed them where the scientists couldn't," said Hides, who with his wife, Linda, operates the world's only commercial lungfish farm at Howard, near Maryborough.And they export young lungfish to fish fanciers all over the world at $500 each."There's been a lot of talk, with scientists getting on the bandwagon, about the Traveston dam killing lungfish and making them extinct and it's a whole lot of garbage," he said.Hides, 67, said scientists had said female lungfish laid 100 eggs which were individually fertilised by the male."That's poppycock," he said. "One big old female can lay 15,000 eggs and it would be impossible for the male to fertilise them all. They are pea-sized eggs, and in the wild, everything from insects to fish and snakes will eat them."When the young hatch, they lie on their sides for the first couple of weeks, hardly moving at all, and sometimes they go back into their eggs."The Hides feed algae and black worms to the fry and for the first month, they are slow growers. After 12 months, the lungfish are 30cm long.Working with Department of Primary Industries officers, Hides said the biggest lungfish he had seen was a 1.4m specimen, probably 100 years old.When the young reach about 15cm long, they are individually placed in plastic boxes, kept wet and shipped to public aquariums, commercial marine attractions, private collectors and scientific establishments worldwide."We've never lost one," he said. "We sell over the internet to collectors in South Africa, Germany, the United Kingdom, Thailand, Korea and the US. Japan is our biggest market." Recently, British wildlife filmmaker Sir David Attenborough visited the Hides' 5ha property with its array of concrete tanks, to film lungfish for his latest nature series, Life in Cold Blood.Reaching this point has been a long haul for the Hides."We pestered the government for nearly 20 years before we got a licence to breed lungfish, then it was another five years of applications to get an export licence," he said.In 2001, the couple achieved the first of four successful spawnings. They have 10 large breeding lungfish and another 10 "future breeders". The fourth and most recent spawning has given the couple young lungfish worth about $3.5 million.Now they're ready for a break. At 67, Hides' health is failing."We have not had a day off for 10 years," he said."You're sitting there waiting for them to breed. There's some stress in it all and we are not getting any younger."If you've a lazy $1.5 million, the Hides would like to hear from you. Visit their lungfish website: www.ceratodus.com
Wednesday, January 23, 2008
Nonlinear Ecosystem Response Points To Environmental Solutions
The preservation of coastal ecosystem services such as clean water, storm buffers or fisheries protection does not have to be an all-or-nothing approach, a new study indicates, and a better understanding of how ecosystems actually respond to protection efforts in a "nonlinear" fashion could help lead the way out of environmental-versus-economic gridlock।
There may be much better ways to provide the majority of environmental protection needed while still maintaining natural resource-based jobs and sustainable communities, scientists from 13 universities and research institutes will suggest January 18 in a new article in the journal Science.
"The very concept of ecosystem-based management implies that humans are part of the equation, and their needs also have to be considered," said Lori Cramer, an associate professor of sociology at Oregon State University.
"But ecosystem concerns have too often been viewed as an all-or-none choice, and it doesn't have to be that way," Cramer said. "What we are learning is that sometimes a little environmental protection can go a long way, and leave room for practical compromises."
In their analysis, a diverse group of scientists from four nations analyzed the values and uses of mangrove forests in Thailand -- a hot spot of concern about coastal ecosystems being degraded and losing their traditional value of storm protection, wood production and fish habitat. These saltwater forests are frequently being replaced with commercial shrimp farms.
In the past, the scientists said, it was often assumed that the environment responded to protection efforts in a "linear" fashion -- in other words, protecting twice as much of a resource generated twice the amount of protection. But the new study, and others like it, are making it more clear that ecosystems respond in a "nonlinear" fashion -- protection of a small percentage of a resource might result in a large percentage of the maximum benefit that can be gained.
If the data are available to help quantify goods and services, researchers say, values can be attached to them and used to reach societal compromises. This might lead to most -- but not all -- of an environmental resource being protected, and some -- but not all -- of resources available for commercial use. The combined value of the ecosystem protection and commercial development may approach, or even exceed the value of a "hands-off" approach.
"Part of the problem now is that a lot of the data we need to make this type of assessment simply isn't available," said Sally Hacker, an OSU associate professor of zoology. "Biological, economic and sociological data could be enormously helpful to help us reach better management decisions, and this is something we need to improve."
Fairly good data were available in the case of the Thailand mangrove forests, however, and researchers used it to make their case. On a given area of mangrove forest there, the assigned value of ecosystem services -- storm protection, biological habitat, etc. -- was determined to be about $19 million with a "hands-off" approach and no commercial use whatsoever.
But with a full range of uses, which included leaving 80 percent of the area in mangrove forests and gaining almost all of their flood protection ability, the value was found to be $17.5 million, Hacker said. And this allowed for a commercial shrimp fishery, gathering of wood products, fishing and other commercial uses.
"At some point we have to get beyond this 'either-or' mentality when it comes to land and ocean management," Cramer said. "Insisting that our ecosystems be either totally protected, or totally developed, just leads to polarization, entrenched positions and a loss of communication. We can do better than that, and a good scientific approach can help show the way."
In the final analysis, the researchers said, everything should be on the table -- the value of ecosystem services, the protection of species and the environment, jobs, tourism, protection of human life, even cultural and community values.
"Shrimp farming may be a person's livelihood, and that cannot be ignored," Cramer said. "At the same time these mangrove forests help protect human lives and healthy ecosystems, and you can't ignore that either. The good news is that when we understand the nonlinear nature of ecosystem response, some of these compromises become possible."
The concepts being developed, the researchers said, are directly relevant to the current debate over marine reserves in Oregon. The challenge there will be to balance an adequate amount of biological protection, and a careful analysis of the areas to be protected, with the needs and concerns of coastal communities, they said.
In like fashion, they said, such approaches may be relevant to many other societal debates -- whether it's health care or the preservation of protective marshes around New Orleans -- in which values can be assigned to various services and compromises reached.
Adapted from materials provided by Oregon State University.
"The very concept of ecosystem-based management implies that humans are part of the equation, and their needs also have to be considered," said Lori Cramer, an associate professor of sociology at Oregon State University.
"But ecosystem concerns have too often been viewed as an all-or-none choice, and it doesn't have to be that way," Cramer said. "What we are learning is that sometimes a little environmental protection can go a long way, and leave room for practical compromises."
In their analysis, a diverse group of scientists from four nations analyzed the values and uses of mangrove forests in Thailand -- a hot spot of concern about coastal ecosystems being degraded and losing their traditional value of storm protection, wood production and fish habitat. These saltwater forests are frequently being replaced with commercial shrimp farms.
In the past, the scientists said, it was often assumed that the environment responded to protection efforts in a "linear" fashion -- in other words, protecting twice as much of a resource generated twice the amount of protection. But the new study, and others like it, are making it more clear that ecosystems respond in a "nonlinear" fashion -- protection of a small percentage of a resource might result in a large percentage of the maximum benefit that can be gained.
If the data are available to help quantify goods and services, researchers say, values can be attached to them and used to reach societal compromises. This might lead to most -- but not all -- of an environmental resource being protected, and some -- but not all -- of resources available for commercial use. The combined value of the ecosystem protection and commercial development may approach, or even exceed the value of a "hands-off" approach.
"Part of the problem now is that a lot of the data we need to make this type of assessment simply isn't available," said Sally Hacker, an OSU associate professor of zoology. "Biological, economic and sociological data could be enormously helpful to help us reach better management decisions, and this is something we need to improve."
Fairly good data were available in the case of the Thailand mangrove forests, however, and researchers used it to make their case. On a given area of mangrove forest there, the assigned value of ecosystem services -- storm protection, biological habitat, etc. -- was determined to be about $19 million with a "hands-off" approach and no commercial use whatsoever.
But with a full range of uses, which included leaving 80 percent of the area in mangrove forests and gaining almost all of their flood protection ability, the value was found to be $17.5 million, Hacker said. And this allowed for a commercial shrimp fishery, gathering of wood products, fishing and other commercial uses.
"At some point we have to get beyond this 'either-or' mentality when it comes to land and ocean management," Cramer said. "Insisting that our ecosystems be either totally protected, or totally developed, just leads to polarization, entrenched positions and a loss of communication. We can do better than that, and a good scientific approach can help show the way."
In the final analysis, the researchers said, everything should be on the table -- the value of ecosystem services, the protection of species and the environment, jobs, tourism, protection of human life, even cultural and community values.
"Shrimp farming may be a person's livelihood, and that cannot be ignored," Cramer said. "At the same time these mangrove forests help protect human lives and healthy ecosystems, and you can't ignore that either. The good news is that when we understand the nonlinear nature of ecosystem response, some of these compromises become possible."
The concepts being developed, the researchers said, are directly relevant to the current debate over marine reserves in Oregon. The challenge there will be to balance an adequate amount of biological protection, and a careful analysis of the areas to be protected, with the needs and concerns of coastal communities, they said.
In like fashion, they said, such approaches may be relevant to many other societal debates -- whether it's health care or the preservation of protective marshes around New Orleans -- in which values can be assigned to various services and compromises reached.
Adapted from materials provided by Oregon State University.
Tuesday, January 22, 2008
Climate Influences Deep Sea Populations
In a new article Joan B. Company and colleagues at the Institut de Ciències del Mar (CSIC) in Spain describe a mechanism of interaction across ecosystems showing how a climate-driven phenomenon originated in shelf environments controls the biological processes of a deep-sea living resource।
The progressive depletion of world fisheries is one of the key socio-economical issues of the forthcoming century. However, amid this worrying scenario, Company's study demonstrates how a climate-induced phenomenon occurring at a decadal time-scale, such as the formation of dense shelf waters and its subsequent downslope cascading can repeatedly reverse the general trend of overexploitation of a deep-sea living resource.
Strong downslope currents associated with intense cascading events displace the population of the shrimp Aristeus antennatus from the fishing grounds, producing a temporary fishery collapse. However, nutritive particles brought by cascading waters to deep regions cause an enhancement of its recruitment process and an increase of its total landings during the following years.
These new findings resolve the paradox of a long-overexploited fishery that has not collapsed after 70 years of intense deep-sea trawling. The results will have a high socio-economic impact, since this species is the most valuable deep-sea living resource in the Mediterranean Sea. Because the cascading of dense water from continental shelves is a global phenomenon whose effects on biological processes were not considered in the past, it is hypothesized that its influence on deep-sea ecosystems and fisheries worldwide should be more important than previously thought.
In this sense, applying the findings to a global fishery scenario, shelf water cascading sites identified worldwide could be considered as regions favorable for deep-sea demersal fisheries, just as the upwelling zones are considered favorable regions for pelagic fisheries. This paper is particularly timely, since these new results will be of special relevance to the current debate on the shift from shelf to deep-sea fisheries.
*Journal reference: Company JB, Puig P, Sardà F, Palanques A, Latasa M, et al (2008) Climate Influence on Deep Sea Populations. PLoS ONE 3(1): e1431.doi:10.1371/journal.pone.0001431 http://www.plosone.org/doi/pone.0001431
Adapted from materials provided by Public Library of Science, via EurekAlert!, a service of AAAS.
Strong downslope currents associated with intense cascading events displace the population of the shrimp Aristeus antennatus from the fishing grounds, producing a temporary fishery collapse. However, nutritive particles brought by cascading waters to deep regions cause an enhancement of its recruitment process and an increase of its total landings during the following years.
These new findings resolve the paradox of a long-overexploited fishery that has not collapsed after 70 years of intense deep-sea trawling. The results will have a high socio-economic impact, since this species is the most valuable deep-sea living resource in the Mediterranean Sea. Because the cascading of dense water from continental shelves is a global phenomenon whose effects on biological processes were not considered in the past, it is hypothesized that its influence on deep-sea ecosystems and fisheries worldwide should be more important than previously thought.
In this sense, applying the findings to a global fishery scenario, shelf water cascading sites identified worldwide could be considered as regions favorable for deep-sea demersal fisheries, just as the upwelling zones are considered favorable regions for pelagic fisheries. This paper is particularly timely, since these new results will be of special relevance to the current debate on the shift from shelf to deep-sea fisheries.
*Journal reference: Company JB, Puig P, Sardà F, Palanques A, Latasa M, et al (2008) Climate Influence on Deep Sea Populations. PLoS ONE 3(1): e1431.doi:10.1371/journal.pone.0001431 http://www.plosone.org/doi/pone.0001431
Adapted from materials provided by Public Library of Science, via EurekAlert!, a service of AAAS.
Thursday, September 13, 2007
Mediterranean's rich marine life under threat
Climate change has warmed up the Mediterranean Sea and threatens its rich animal and plant life, Italy's Institute of Marine Research (ICRAM) warned in a new report Tuesday. The alarm bell came a day before the start of a national conference on climate change in Rome.The experts said a cold current emanating from the Gulf of Trieste off northern Italy, which allowed the waters of the Adriatic and the Mediterranean to mix, had vanished since 2003 due to warming.This threatened to turn the Adriatic Sea into a salt lake with no marine life, it said.The body said the warming of the Mediterranean Sea prevented the mixing of waters and could lead to the disappearance of micro-algae crucial to the marine food chain.Temperature rises of 0.4 degrees Centigrade could "alter up to 50 percent of the species," it said.Italy's Environment Minister Alfonso Pecoraro Scanio on Monday termed the situation "a national crisis."He is due to inaugurate Wednesday's conference along with Jacques Diouf, the head of the UN Food and Agriculture Organisation.The conference will also discuss the melting of Alpine glaciers, drought, desertification and the choking of the lagoon at Venice and in the northern Adriatic.
Thursday, May 24, 2007
Antarctic "cradle of life"
Carnivorous sponges, 585 new species of crustaceans and hundreds of new worms have been discovered in the dark waters around Antarctica, suggesting these depths may have been the source of much marine life, European researchers reported on Wednesday।
The team, who scooped samples from as deep as 20,000 feet , found unexpectedly rich diversity of animal life.
Many belong to species found around the world, notably in the Arctic, while others appear to be unique to the deepest Antarctic waters, the researchers reported in the journal Nature.
The unique species tend to be the kind that do not spread easily, which suggests the deep, cold southern oceans may have been the source of many types of marine life, the researchers conclude.
"The Antarctic deep sea is potentially the cradle of life of the global marine species. Our research results challenge suggestions that the deep sea diversity in the Southern Ocean is poor," said Angelika Brandt of the Zoological Institute and Zoological Museum at Germany's University of Hamburg.
"We now have a better understanding in the evolution of the marine species and how they can adapt to changes in climate and environments," Brandt, who led the expedition, said in a statement.
Among the new creatures they documented are a gourd-shaped carnivorous sponge called Chondrocladia; free-swimming worms and 674 species of isopod, a diverse order of crustaceans that includes woodlice, also commonly called pillbugs, sea lice or sea centipedes.
Of the isopod crustaceans, 585 species had never been seen before.
Between 2002 and 2005, researchers sampled water and the sediment from 2,500 to 20,000 feet in the deep Weddell Sea and adjacent areas.
Their catch was surprisingly rich.
"What was once thought to be a featureless abyss is in fact a dynamic, variable and biologically rich environment," Katrin Linse, a marine biologist from the British Antarctic Survey, said in a statement.
The researchers said the Weddell Sea is an important source of deep water for the rest of the ocean. Species can enter the depths of the Weddell sea from shallower continental shelves.
Animals that spread easily, such as the single-celled Foraminifera, were similar to those found in other oceans.
"The isopods, ostracods (seed shrimp) and nematodes, which are poor dispersers, include many species currently known only from the Southern Ocean," the researchers wrote.
Many belong to species found around the world, notably in the Arctic, while others appear to be unique to the deepest Antarctic waters, the researchers reported in the journal Nature.
The unique species tend to be the kind that do not spread easily, which suggests the deep, cold southern oceans may have been the source of many types of marine life, the researchers conclude.
"The Antarctic deep sea is potentially the cradle of life of the global marine species. Our research results challenge suggestions that the deep sea diversity in the Southern Ocean is poor," said Angelika Brandt of the Zoological Institute and Zoological Museum at Germany's University of Hamburg.
"We now have a better understanding in the evolution of the marine species and how they can adapt to changes in climate and environments," Brandt, who led the expedition, said in a statement.
Among the new creatures they documented are a gourd-shaped carnivorous sponge called Chondrocladia; free-swimming worms and 674 species of isopod, a diverse order of crustaceans that includes woodlice, also commonly called pillbugs, sea lice or sea centipedes.
Of the isopod crustaceans, 585 species had never been seen before.
Between 2002 and 2005, researchers sampled water and the sediment from 2,500 to 20,000 feet in the deep Weddell Sea and adjacent areas.
Their catch was surprisingly rich.
"What was once thought to be a featureless abyss is in fact a dynamic, variable and biologically rich environment," Katrin Linse, a marine biologist from the British Antarctic Survey, said in a statement.
The researchers said the Weddell Sea is an important source of deep water for the rest of the ocean. Species can enter the depths of the Weddell sea from shallower continental shelves.
Animals that spread easily, such as the single-celled Foraminifera, were similar to those found in other oceans.
"The isopods, ostracods (seed shrimp) and nematodes, which are poor dispersers, include many species currently known only from the Southern Ocean," the researchers wrote.
Thursday, March 29, 2007
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