Intensity of hurricanes: New study helps improve predictions of storm intensity

They are something we take very seriously in Florida — hurricanes. The names roll off the tongue like a list of villains — Andrew, Charlie, Frances and Wilma.In the past 25 years or so, experts have gradually been improving prediction of the course a storm may take. This is thanks to tremendous advancements in computer and satellite technology. While we still have the “cone of uncertainty” we’ve become familiar with watching television weather reports, today’s models are more accurate than they used to be.The one area, however, where there is still much more to be researched and learned is in predicting just how intense a storm may be. While hurricane hunter aircraft can help determine wind speed, velocity, water temperature and other data, the fact is we often don’t know why or how a storm gets stronger or weaker. There has been virtually no progress in hurricane intensity forecasting during the last quarter century.But, thanks to new research being conducted, all that’s about to change.”The air-water interface — whether it had significant waves or significant spray — is a big factor in storm intensity,” said Alex Soloviev, Ph.D., a professor at Nova Southeastern University’s Oceanographic Center. “Hurricanes gain heat energy through the interface and they lose mechanical energy at the interface.”Soloviev is also an Adjunct Professor at the University of Miami Rosenstiel School of Marine and Atmospheric Science (UM RSMAS) and a Fellow at the Cooperative Institute for Marine and Atmospheric Studies (CIMAS.) He and his fellow researchers used a computational fluid dynamics model to simulate microstructure of the air-sea interface under hurricane force winds. In order to verify these computer-generated results, the group conducted experiments at the UM’s Rosenstiel School Air-Sea Interaction Salt Water Tank (ASIST) where they simulated wind speed and ocean surface conditions found during hurricanes.The study “The Air-Sea Interface and Surface Stress Under Tropical Cyclones” was published in the June 16, 2014 issue of the journal Nature Scientific Reports. Soloviev was the lead author of this study, which was conducted by a multi-institutional team including Roger Lukas (University of Hawaii), Mark Donelan and Brian Haus (UM RSMAS), and Isaac Ginis (University of Rhode Island.)The researchers were surprised at what they found. Under hurricane force wind, the air-water interface was producing projectiles fragmenting into sub millimeter scale water droplets. …

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Antibiotics from mangroves?

Researchers at the Universiti Teknologi MARA (UiTM) in Malaysia have conducted a study on the mangrove ecosystem to search for actinomycetes bacteria. The mangrove ecosystem is known as a highly productive habitat for isolating actinomycetes, which has the potential of producing biologically active secondary metabolites.The UiTM study focused on eight different mangrove sites in Malaysia, which were chosen at random to isolate and screen actinomycetes from soil samples. A total of 53 possible marine actinomycetes were isolated and it was found that a three percent concentration of sodium chloride was sufficient to support the growth of marine actinomycetes.Among the isolated filamentous bacteria, five isolates showed antimicrobial activity from direct culture broth against at least one of the test organisms. Meanwhile, four extracts of ethyl acetate showed activity against Gram-positive test organisms. The results revealed that marine actinomycetes is a potential source for producing antibiotics.Story Source:The above story is based on materials provided by Universiti Teknologi MARA (UiTM). Note: Materials may be edited for content and length.

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Dust in the wind drove iron fertilization during ice age

Researchers from Princeton University and the Swiss Federal Institute of Technology in Zurich have confirmed that during the last ice age iron fertilization caused plankton to thrive in a region of the Southern Ocean.The study published in Science confirms a longstanding hypothesis that wind-borne dust carried iron to the region of the globe north of Antarctica, driving plankton growth and eventually leading to the removal of carbon dioxide from the atmosphere.Plankton remove the greenhouse gas carbon dioxide (CO2) from the atmosphere during growth and transfer it to the deep ocean when their remains sink to the bottom. Iron fertilization has previously been suggested as a possible cause of the lower CO2 levels that occur during ice ages. These decreases in atmospheric CO2 are believed to have “amplified” the ice ages, making them much colder, with some scientists believing that there would have been no ice ages at all without the CO2 depletion.Iron fertilization has also been suggested as one way to draw down the rising levels of CO2 associated with the burning of fossil fuels. Improved understanding of the drivers of ocean carbon storage could lead to better predictions of how the rise in manmade carbon dioxide will affect climate in the coming years.The role of iron in storing carbon dioxide during ice ages was first proposed in 1990 by the late John Martin, an oceanographer at Moss Landing Marine Laboratories in California who made the landmark discovery that iron limits plankton growth in large regions of the modern ocean.Based on evidence that there was more dust in the atmosphere during the ice ages, Martin hypothesized that this increased dust supply to the Southern Ocean allowed plankton to grow more rapidly, sending more of their biomass into the deep ocean and removing CO2 from the atmosphere. Martin focused on the Southern Ocean because its surface waters contain the nutrients nitrogen and phosphorus in abundance, allowing plankton to be fertilized by iron without running low on these necessary nutrients.The research confirms Martin’s hypothesis, said Daniel Sigman, Princeton’s Dusenbury Professor of Geological and Geophysical Sciences, and a co-leader of the study. “I was an undergraduate when Martin published his ‘ice age iron hypothesis,'” he said. “I remember being captivated by it, as was everyone else at the time. But I also remember thinking that Martin would have to be the luckiest person in the world to pose such a simple, beautiful explanation for the ice age CO2 paradox and then turn out to be right about it.”Previous efforts to test Martin’s hypothesis established a strong correlation of cold climate, high dust and productivity in the Subantarctic region, a band of ocean encircling the globe between roughly 40 and 50 degrees south latitude that lies in the path of the winds that blow off South America, South Africa and Australia. However, it was not clear whether the productivity was due to iron fertilization or the northward shift of a zone of naturally occurring productivity that today lies to the south of the Subantarctic. This uncertainty was made more acute by the finding that ice age productivity was lower in the Antarctic Ocean, which lies south of the Subantarctic region.To settle the matter, the research groups of Sigman at Princeton and Gerald Haug and Tim Eglinton at ETH Zurich teamed up to use a new method developed at Princeton. …

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Legal harvest of marine turtles tops 42,000 each year

A new study has found that 42 countries or territories around the world permit the harvest of marine turtles — and estimates that more than 42,000 turtles are caught each year by these fisheries.The research, carried out by Blue Ventures Conservation and staff at the University of Exeter’s Centre for Ecology and Conservation, is the first to comprehensively review the number of turtles currently taken within the law and assess how this compares to other global threats to the creatures.All seven marine turtle species are currently listed on the IUCN Red List of Threatened Species.Frances Humber of Blue Ventures and a PhD student at the University of Exeter, who led the research, said: “This is the first study to comprehensively review the legal take of turtles in recent years, and allows us to assess the relative fisheries threats to this group of species. Despite increased national and international protection of marine turtles, direct legal take remains a major source of mortality. However, it is likely that a fraction of current marine turtle mortality take is legal, with greater threats from illegal fisheries and bycatch.”The first marine turtle harvest legislation was instigated in Bermuda in 1620 to protect “so excellent a fishe” and prohibited taking any turtle “under eighteen inches in the breadth or diameter.”But large scale commercial taking of turtles continued all over the world for centuries, with global capture peaking at over 17,000 tonnes in the late 1960s. For example, during the peak of Mexico’s sea turtle exploitation in 1968 it is estimated that the national take was over 380,000 turtles.Increased conservation awareness at an international scale has led to greater protection of marine turtles, with 178 countries now signed up to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) restricting the international trade of turtle products.The direct take of turtles has continued legally in many regions and countries, often for traditional coastal communities to support themselves or small-scale fisheries supplying local markets with meat, and sometimes shell. The fisheries are an important source of finance, protein and cultural identity, but information can be scarce on their status — despite often being listed as one of the major threats to turtle populations.The researchers collated data for all seven species of marine turtles from over 500 publications and 150 in-country experts.They estimate that currently more than 42,000 marine turtles are caught each year legally, of which over 80% are green turtles. Legal fisheries are concentrated in the wider Caribbean region, including several of the UKs Overseas Territories, and the Indo-Pacific region, with Papua New Guinea, Nicaragua and Australia together accounting for almost three quarters of the total.The data indicates that since the 1980s more than 2 million turtles have been caught, although current levels are less than 60% of those in the 1980s.Bycatch — the unwanted fish and other marine creatures trapped by commercial fishing nets during fishing for a different species — is thought to be a far higher cause of death for marine turtles, likely running into hundreds of thousands each year.Illegal fishing also continues to be a major cause of mortality, with the researchers estimating a minimum of 65,000 turtles taken from Mexico alone since the year 2000. The scale of global illegal capture is likely to be severely underreported due to the difficulties collecting information on such an activity.Dr Annette Broderick, of the Centre for Ecology and Conservation at the University of Exeter’s Penryn Campus in Cornwall, added: “We were surprised to find that there are 42 countries with no legislation in place that prohibits the harvest of marine turtles, although for many of these countries these harvests provide important sources of protein or income. It is however important to ensure that these fisheries are operating at a sustainable level.”Story Source:The above story is based on materials provided by University of Exeter. Note: Materials may be edited for content and length.

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Theory on origin of animals challenged: Some animals need extremely little oxygen

One of science’s strongest dogmas is that complex life on Earth could only evolve when oxygen levels in the atmosphere rose to close to modern levels. But now studies of a small sea sponge fished out of a Danish fjord shows that complex life does not need high levels of oxygen in order to live and grow.The origin of complex life is one of science’s greatest mysteries. How could the first small primitive cells evolve into the diversity of advanced life forms that exists on Earth today? The explanation in all textbooks is: Oxygen. Complex life evolved because the atmospheric levels of oxygen began to rise app. 630 — 635 million years ago.However new studies of a common sea sponge from Kerteminde Fjord in Denmark shows that this explanation needs to be reconsidered. The sponge studies show that animals can live and grow even with very limited oxygen supplies.In fact animals can live and grow when the atmosphere contains only 0.5 per cent of the oxygen levels in today’s atmosphere.”Our studies suggest that the origin of animals was not prevented by low oxygen levels,” says Daniel Mills, PhD at the Nordic Center for Earth Evolution at the University of Southern Denmark.Together with Lewis M. Ward from the California Institute of Technology he is the lead author of a research paper about the work in the journal PNAS.A little over half a billion years ago, the first forms of complex life — animals — evolved on Earth. Billions of years before that life had only consisted of simple single-celled life forms. The emergence of animals coincided with a significant rise in atmospheric oxygen, and therefore it seemed obvious to link the two events and conclude that the increased oxygen levels had led to the evolution of animals.”But nobody has ever tested how much oxygen animals need — at least not to my knowledge. …

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Arctic marine mammals are ecosystem sentinels

As the Arctic continues to see dramatic declines in seasonal sea ice, warming temperatures and increased storminess, the responses of marine mammals can provide clues to how the ecosystem is responding to these physical drivers.Seals, walruses and polar bears rely on seasonal sea ice for habitat and must adapt to the sudden loss of ice, while migratory species such as whales appear to be finding new prey, altering migration timing and moving to new habitats.”Marine mammals can act as ecosystem sentinels because they respond to climate change through shifts in distribution, timing of their movements and feeding locations,” said Sue Moore, Ph.D., a NOAA oceanographer, who spoke today at the annual meeting of the American Association for the Advancement of Science in Chicago. “These long-lived mammals also reflect changes to the ecosystem in their shifts in diet, body condition and physical health.”Moore, who was part of a panel of U.S. and Canadian scientists on the health of marine mammals and indigenous people in the Arctic, stressed the importance of integrating marine mammal health research into the overall climate, weather, oceanographic and social science research on changes in the Arctic.”Marine mammals connect people to ecosystem research by making it relevant to those who live in the Arctic and depend on these mammals for diet and cultural heritage and people around the world who look to these animals as symbols of our planet’s health,” Moore said.Story Source:The above story is based on materials provided by National Oceanic and Atmospheric Administration. Note: Materials may be edited for content and length.

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Fish living near the equator will not thrive in the warmer oceans of the future

According to an international team of researchers, the rapid pace of climate change is threatening the future presence of fish near the equator.”Our studies found that one species of fish could not even survive in water just three degrees Celsius warmer than what it lives in now,” says the lead author of the study, Dr Jodie Rummer from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University.Dr Rummer and her colleagues studied six common species of fish living on coral reefs near the equator. She says many species in this region only experience a very narrow range of temperatures over their entire lives, and so are likely adapted to perform best at those temperatures.This means climate change places equatorial marine species most at risk, as oceans are projected to warm by two to three degrees Celsius by the end of this century.”Such an increase in warming leads to a loss of performance,” Dr Rummer explains. “Already, we found four species of fish are living at or above the temperatures at which they function best.”The team measured the rates at which fish use oxygen, the fuel for metabolism, across different temperatures — at rest and during maximal performance. According to the results, at warmer temperatures fish lose scope for performance. In the wild, this would limit activities crucial to survival, such as evading predators, finding food, and generating sufficient energy to breed.Because many of Earth’s equatorial populations are now living close to their thermal limits, there are dire consequences ahead if these fish cannot adapt to the pace at which oceans are warming.Dr Rummer suggests there will be declines in fish populations as species may move away from the equator to find refuge in areas with more forgiving temperatures.”This will have a substantial impact on the human societies that depend on these fish,” she says.A concentration of developing countries lies in the equatorial zone, where fish are crucial to the livelihoods and survival of millions of people, including those in Papua New Guinea and Indonesia.In an era of rapid climate change, understanding the link between an organism and its environment is crucial to developing management strategies for the conservation of marine biodiversity and the sustainable use of marine fisheries.”This is particularly urgent when considering food security for human communities.”Story Source:The above story is based on materials provided by ARC Centre of Excellence in Coral Reef Studies. Note: Materials may be edited for content and length.

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Giant mass extinction quicker than previously thought: End-Permian extinction happened in 60,000 years

The largest mass extinction in the history of animal life occurred some 252 million years ago, wiping out more than 96 percent of marine species and 70 percent of life on land — including the largest insects known to have inhabited Earth. Multiple theories have aimed to explain the cause of what’s now known as the end-Permian extinction, including an asteroid impact, massive volcanic eruptions, or a cataclysmic cascade of environmental events. But pinpointing the cause of the extinction requires better measurements of how long the extinction period lasted.Now researchers at MIT have determined that the end-Permian extinction occurred over 60,000 years, give or take 48,000 years — practically instantaneous, from a geologic perspective. The new timescale is based on more precise dating techniques, and indicates that the most severe extinction in history may have happened more than 10 times faster than scientists had previously thought.”We’ve got the extinction nailed in absolute time and duration,” says Sam Bowring, the Robert R. Shrock Professor of Earth and Planetary Sciences at MIT. “How do you kill 96 percent of everything that lived in the oceans in tens of thousands of years? It could be that an exceptional extinction requires an exceptional explanation.”In addition to establishing the extinction’s duration, Bowring, graduate student Seth Burgess, and a colleague from the Nanjing Institute of Geology and Paleontology also found that, 10,000 years before the die-off, the oceans experienced a pulse of light carbon, which likely reflects a massive addition of carbon dioxide to the atmosphere. This dramatic change may have led to widespread ocean acidification and increased sea temperatures by 10 degrees Celsius or more, killing the majority of sea life.But what originally triggered the spike in carbon dioxide? The leading theory among geologists and paleontologists has to do with widespread, long-lasting volcanic eruptions from the Siberian Traps, a region of Russia whose steplike hills are a result of repeated eruptions of magma. To determine whether eruptions from the Siberian Traps triggered a massive increase in oceanic carbon dioxide, Burgess and Bowring are using similar dating techniques to establish a timescale for the Permian period’s volcanic eruptions that are estimated to have covered over five million cubic kilometers.”It is clear that whatever triggered extinction must have acted very quickly,” says Burgess, the lead author of a paper that reports the results in this week’s Proceedings of the National Academy of Sciences, “fast enough to destabilize the biosphere before the majority of plant and animal life had time to adapt in an effort to survive.”Pinning dates on an extinctionIn 2006, Bowring and his students made a trip to Meishan, China, a region whose rock formations bear evidence of the end-Permian extinction; geochronologists and paleontologists have flocked to the area to look for clues in its layers of sedimentary rock. …

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Researchers discover rare new species of deep-diving whale

Researchers have identified a new species of mysterious beaked whale based on the study of seven animals stranded on remote tropical islands in the Indian and Pacific Oceans over the past 50 years.Beaked whales, a widespread but little-known family of toothed whales distantly related to sperm whales, are found in deep ocean waters beyond the edge of the continental shelf throughout the world’s oceans.”They are rarely seen at sea due to their elusive habits, long dive capacity and apparent low abundance for some species. Understandably, most people have never heard of them,” says international team leader, Dr Merel Dalebout, a visiting research fellow at UNSW.The study of the new species, Mesoplodon hotaula, is published in the journal Marine Mammal Science.The first specimen was a female found on a Sri Lankan beach more than 50 years ago.On 26 January 1963, a 4.5 metre-long, blue-grey beaked whale washed up at Ratmalana near Colombo. The then director of the National Museums of Ceylon, P.E.P (Paulus) Deraniyagala, described it as a new species, and named it Mesoplodon hotaula, after the local Singhala words for ‘pointed beak’.However, two years later, other researchers reclassified this specimen as an existing species, Mesoplodon ginkgodens, named for the tusk-like teeth of the adult males that are shaped like the leaves of a ginkgo tree.”Now it turns out that Deraniyagala was right regarding the uniqueness of the whale he identified. While it is closely related to the ginkgo-toothed beaked whale, it is definitely not the same species,” says Dr Dalebout.The researchers used a combination of DNA analysis and physical characteristics to identify the new species from seven specimens found stranded in Sri Lanka, the Gilbert Islands (now Kiribati), Palmyra Atoll in the Northern Line Islands near Hawai’i, the Maldives, and the Seychelles.The new specimens are held by various institutions and groups, including the US Smithsonian National Museum in Washington DC, the Island Conservation Society in the Seychelles, and the University of Auckland, New Zealand. The genetic analyses were conducted as part of an international collaboration with the US NMFS Southwest Fisheries Science Center and Oregon State University.The researchers were able to get good quality DNA from tissue samples from only one specimen. For the others, they drilled the bones of the whales in order to analyse short fragments of ‘ancient DNA’ relying on techniques commonly used with old sub-fossil material from extinct species.The researchers also studied all other known beaked whale species to confirm the distinctiveness of Deraniyagala’s whale, including six specimens of the closely related, gingko-toothed beaked whale.”A number of species in this group are known from only a handful of animals, and we are still finding new ones, so the situation with Deraniyagala’s whale is not that unusual,” Dr Dalebout says.”For example, the ginkgo-toothed beaked whale, first described in 1963, is only known from about 30 strandings and has never been seen alive at sea with any certainty. It’s always incredible to me to realise how little we really do know about life in the oceans. There’s so much out there to discover. “Over the last 10 years or so, two other new beaked whales have come to light; both through research in which Dr Dalebout was involved. In 2002, Mesoplodon perrini or Perrin’s beaked whale, was described from the eastern North Pacific, and in 2003, Mesoplodon traversii, the spade-toothed whale, was described from the Southern Ocean. …

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Sneezing sponges suggest existence of sensory organ: Discovery challenges assumptions about ‘primitive’ organism

When Danielle Ludeman decided to leave her hometown of Vancouver to study evolutionary biology at the University of Alberta, she knew she was in for a challenge that would help her discover things about science and, in turn, herself.What she didn’t count on were the hours, days and months she’d spend watching sponges in mid-sneeze.It sounds like a strange way to pass time, but sneezing sponges have become a major part of Ludeman’s studies at the U of A, including a new paper that points to the sneeze as evidence of a sensory organ in one of the most basic multicellular organisms on Earth.”The sneeze can tell us a lot about how the sponge works and how it’s responding to the environment,” said Ludeman, a master’s student in the Faculty of Science. “This paper really gets at the question of how sensory systems evolved. The sponge doesn’t have a nervous system, so how can it respond to the environment with a sneeze the way another animal that does have a nervous system can?”Ludeman started the work as part of an undergraduate research honours project, working under the supervision of Sally Leys, Canada Research Chair in Evolutionary Developmental Biology. It was Leys and a former graduate student who first discovered that sponges do in fact sneeze.The sponge is a filter feeder that relies totally on water flow through its body for food, oxygen and waste removal. Sneezing, a 30- to 45-minute process that sees the entire body of the sponge expand and contract, allows it to respond to physical stimuli such as sediment in the water.Time-lapse sneezesFor their study, Ludeman and Leys used a variety of drugs to elicit sneezes in freshwater sponges and observed the process using fluorescent dye — all recorded using time-lapse video. Their efforts focused on the sponge’s osculum, which controls water exiting the organism, including water expelled during a sneeze.Through a series of lab experiments, the pair discovered that ciliated cells lining the osculum play a role in triggering sneezes. In other animals, cilia function like antennae, helping cells respond to stimuli in a co-ordinated manner. In the sponge, their localized presence in the osculum and their sensory function suggest the osculum is in fact a sensory organ.”For a sponge to have a sensory organ is totally new. This does not appear in a textbook; this doesn’t appear in someone’s concept of what sponges are permitted to have,” said Leys.Leys said the discovery raises new questions about how sensory systems may have evolved in the sponge and other animals, including ones with nervous systems. It’s possible this sensory system is unique to the sponge, she said, evolving over the last 600 million years. …

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Drones open way to new world of coral research

Oct. 16, 2013 — Camera-equipped flying robots promise new insights into climate change effects on important ecosystems.Stanford aeronautics graduate student Ved Chirayath photographs coral reefs from below the water using a 360-degree camera.Like undiscovered groves of giant redwoods, centuries-old living corals remain unmapped and unmeasured. Scientists still know relatively little about the world’s biggest corals, where they are and how long they have lived.The secret to unlocking these mysteries may lie with a shoebox-size flying robot.The robot in question is a four-rotor remote-controlled drone developed by Stanford aeronautics graduate student Ved Chirayath. The drone is outfitted with cameras that can film coral reefs from up to 200 feet in the air. Chirayath teamed up with Stanford Woods Institute Senior Fellow Stephen Palumbi to pioneer the use of drone technology to precisely map, measure and study shallow-water reefs off Ofu Island in American Samoa.”Until now the challenges have been too high for flying platforms like planes, balloons and kites,” Palumbi said. “Now send in the drones.”Chirayath, who also works as a scientist at NASA’s Ames Research Center, analyzes the drone’s footage using software he designed. The software removes distortions caused by surface wave movements and enhances resolution. To link the drone aerial footage to close-up images of corals, Chirayath and his colleagues are photographing reefs from below the water using a 360-degree camera. The result is a centimeter-scale optical aerial map and stunning gigapixel panoramic photographs of coral heads that stitch together thousands of images into one.Surveys and maps of rainforests have resulted in new understanding of the vital role these ecosystems play in sustaining the biosphere. Detailed coral maps could do the same, allowing scientists to conduct precise species population surveys over large areas and assess the impact of climate change.The window of time to study these mysterious ecosystems, which provide sustenance and livelihoods to a billion people, may be closing. …

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How red crabs on Christmas Island speak for the tropics

Oct. 10, 2013 — Each year, the land-dwelling Christmas Island red crab takes an arduous and shockingly precise journey from its earthen burrow to the shores of the Indian Ocean where weeks of mating and egg laying await.The crabs represent species that do not factor into a lot of climate-change research. The majority of studies focus on changes in temperate climates, such as the future severity and duration of summers and winters. Tropical animals migrate in response to wet-dry seasons. If fluctuations in rainfall become more extreme and frequent with climate change, then scores of animals could be in trouble.Native to the Australian territories of Christmas Island and the Cocos (Keeling) Islands, millions of the crabs start rolling across the island roads and landscape in crimson waves when the November rains begin. After a two-week scuttle to the sea, the male crab sets up and defends a mating burrow for himself and a female of his kind, the place where she will incubate their clutch for another two weeks. Before the morning of the high tide that precedes the December new moon, the females must emerge to release their millions of eggs into the ocean. A month later, the next generation of crabs comes ashore.But a lack of rain can delay or entirely cancel this meticulous process, according to research conducted through Princeton University that could help scientists understand the consequences of climate change for the millions of migratory animals in Earth’s tropical zones.The researchers report in the journal Global Change Biology that the crabs’ reproductive cycle tracked closely with the amount and timing of precipitation. Writ large, these findings suggest that erratic rainfall could be detrimental to animals that migrate with the dry-wet seasonal cycle that breaks up the tropical year, the researchers report. If fluctuations in rainfall become more extreme and frequent with climate change, then scores of animals could be in trouble — not just the migrators themselves, but also the creatures reliant on them for food.Lead author Allison Shaw, who conducted the work as a Princeton doctoral student in ecology and evolutionary biology, explained that what scientists understand about the possible impact of a warming planet on animal movement is dominated by studies of how creatures that migrate with the summer-to-winter seasonal shifts of Europe and North America will be affected by changes such as the severity and duration of summers and winters. …

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Cultivation of algae, mussels, common reed and microbes could help to improve the Baltic Sea’s condition

Sep. 3, 2013 — The Finnish Environment Institute SYKE has participated in the SUBMARINER project, jointly performed by eight countries in order to investigate new ways of utilising the Baltic Sea’s resources. Over three years, the project has looked at various ways of utilising macroalgae and microalgae, mussels, common reed and microbes. New fish farming methods and future use of wave energy installations in the Baltic Sea were also examined, along with opportunities for using offshore wind park areas for other economic activities.”Executed correctly, these new ways of using the sea would cause no harm to the marine environment. Instead, by cultivating algae, mussels or common reed we can remove nutrients from the sea and even improve its condition,” explains Senior Researcher Jukka Seppälä from SYKE’s Marine Research Centre.With the exception of Russia, all Baltic Sea coastal states are participating in the project. Finland is represented by SYKE. The project is mainly funded by the EU’s Baltic Sea Region Programme, which is aimed at promoting an economically and ecologically sustainable Baltic Sea region.New methods of removing nutrients from the Baltic SeaFinland’s part of the project involved testing of macroalgae cultivation in the sea in Rymättylä and Tvärminne. In addition, the possibilities of cultivating microalgae in under Nordic conditions were investigated.It was discovered that cultivating mussels on substrates constructed of ropes was a more efficient method of removing nutrients from the sea than macroalgae cultivation. The Baltic Sea region’s ice winters pose a specific challenge to mussel and macroalgae cultivation, as the substrates need to be lowered below the water level. The project also looked into the possibilities of using mussel and algae mass as animal feed, fertiliser or in the production of biogas. …

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Bringing coral reefs back from the brink

Sep. 3, 2013 — Shocks caused by climate and seasonal change could be used to aid recovery of some of the world’s badly-degraded coral reefs, an international team of scientists has proposed.A new report by Australian and Swedish marine scientists in the journal Frontiers in Ecology and the Environment suggests that it may be possible to restore living coral cover to a badly-degraded reef system — though not easy.With 70 per cent or more of the world’s coral reefs now assessed as degraded, adopting a business-as-usual approach to how we use and manage reefs is no longer an option, says lead author of the report Nick Graham.”We are unlikely to be able to keep many of the world’s reefs in a pristine state, but with good management we may be able to maintain them in a coral-dominated condition and in some cases we may be able to bring back reefs from a degraded state,” he explains.The researchers have taken heart from examples on land in desertified landscapes; exceptional falls of rain, in combination with controls on grazing pressure, can result in widespread regrowth of natural vegetation.They argue that coral reef managers may be able to take advantage of shocks like tropical storms, periods of cloudy weather or even strong seasonal effects on abundance to restore coral cover on degraded reefs.”Normally we think of these shocks as damaging to coral reefs — but research suggests they are just as damaging to the organisms that can replace coral. In other words, they may act as a circuit-breaker that allows corals to regain control of a reef.”The key to the new thinking is resilience: healthy corals reefs are naturally resilient to shocks — but damaged ones may become overgrown with sea weeds, and the corals vanish.”Weed-dominated systems are pretty resilient too and, once established, it is very hard to restore the corals,” Dr Graham explains.”However a weed-dominated reef can be damaged by big storms too. Cloudy weather and seasonal changes in water temperature can also cause the weeds to die back.”This dieback of weeds opens a window through which corals can re-establish.”The key to bringing back corals is exactly the same as preventing coral cover being lost in the first place, Dr Graham says — reducing human impacts through regulation of fisheries and water quality. If reefs are prepared in this way, they may bounce back when a window for recovery opens.Prof David Bellwood emphasized that “When it comes to saving our coral reefs, prevention is always better than cure and early action is important to slow or reverse degradation.”The researchers emphasize that both protection and recovery of the world’s coral reefs call for a fundamental change in how people interact with and use reef ecosystems.”Until now, the focus has mainly been on conserving small parts of a reef in marine protected areas,” said Prof Bellwood, “- we’re talking about broader approaches to change the relationship between humans and coral reefs to reduce human impacts across the whole ecosystem.”The paper concludes, “Although the composition of coral reefs will likely continue to vary over time, it may be possible to maintain coral-dominated reefs and their associated ecosystem goods and services… Scientists and managers could take advantage of opportunities for change by harnessing shocks and natural variability as potential stimuli for beneficial shifts in ecosystem states.”

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Ocean fish acquire more mercury at depth

Aug. 25, 2013 — Mercury — a common industrial toxin — is carried through the atmosphere before settling on the ocean and entering the marine food web.Now, exciting new research from the University of Michigan and the University of Hawai’i at Manoa School of Ocean and Earth Science and Technology (SOEST) combines biogeochemistry and direct marine ecology observations to show how the global mercury cycle is colliding with ocean fish — and the human seafood supply — at different depths in the water.Mercury accumulation in the ocean fish we eat tends to take place at deeper depths, scientists found, in part because of photochemical reactions that break down organic mercury in well-lit surface waters. More of this accessible organic mercury is also being generated in deeper waters.”A few years ago we published work that showed that predatory fish that feed at deeper depths in the open ocean, like opah and swordfish, have higher mercury concentrations than those that feed in waters near the surface, like mahi-mahi and yellowfin tuna,” said Brian Popp, professor of geology and geophysics at UH Manoa, and a co-author of a new paper scheduled for online publication August 25 in the scientific journal Nature Geoscience. “We knew this was true, but we didn’t know why.””We knew that organic and inorganic mercury dissolved in seawater has a nutrient-like profile, with lower concentrations at the surface and higher concentrations at depth,” said Anela Choy, a PhD candidate in oceanography at UH Manoa. “We saw it in the water, and we saw it in the fish. But we couldn’t explain the gradient we saw, nor did we know exactly where and how the bioavailable organic mercury was entering the marine food web.”Bacteria in the oceans change atmospheric mercury into the organic monomethylmercury form that can accumulate in animal tissue. Large predatory fish contain high levels of methylmercury in part because they eat lots of smaller, mercury-containing fish. In 2009, researchers at UH Manoa determined that the depths at which a species feeds is nearly as important as its position in the food chain in determining how much methylmercury it contains.For the new research, the UH Manoa team worked closely with colleagues at the University of Michigan who used a highly sophisticated mass spectrometer to measure the stable isotopic compositions of mercury in nine species of marine fish that feed at different depths, including six predator fish and three prey fish.Their analysis showed that chemical reactions driven by sunlight destroy up to 80 percent of monomethylmercury in the well-lit upper depths of the central North Pacific Ocean near Hawai’i. The scientists also determined that a significant amount of monomethylmercury must be formed and enter marine food webs in oxygen-poor, deeper waters.The Michigan researchers had previously recorded mercury isotope measurements on fish in the Gulf of Mexico that suggested that up to 50 percent of monomethylmercury was destroyed by photochemical reactions before it was taken up by yellowfin and blackfin tuna living offshore.In Hawaii, the conditions were different — and better — for this type of analysis. “The crystal-clear waters surrounding Hawai’i and the unique information that we had about the depths at which our local fish feed allowed us to clearly identify both the photochemical degradation of monomethylmercury at surface levels and the microbial production of monomethylmercury from inorganic mercury in deeper waters,” Popp said.The finding that mercury is being converted to its toxic, bioavailable form at depth is important in part because scientists expect mercury levels at intermediate depths in the North Pacific to rise in coming decades.”The implication is that predictions for increased mercury in deeper water will result in higher levels in fish,” said Joel Blum of the University of Michigan, the lead author on the new paper and a professor in the department of earth and environmental sciences. …

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Divers willingness to pay for biodiversity could help conservation efforts

Aug. 20, 2013 — Now teeming with life, a new study using the “Tamar Reef” shows that divers assign economic importance to aspects of reef biodiversity. These findings could help underwater conservation efforts.According to the study published in the ICES Journal of Marine Science, divers were willing to pay to improve the reef’s attributes and were able to differentiate and rank their preferences of biodiversity, numbers of fish and corals, coral species richness, fish species richness, coral size, coral abundance, and fish abundance.Respondents ranked biodiversity as the most desirable value, while fish abundance was the least important.”This result was exiting to us, since it shows that the general public as well as scientists place a high value on biodiversity and that visitors understand the fundamentals that constitute a coral reef community,” says Dr. Nadav Shashar of BGU’s Marine Biology and Biotechnology Program in Eilat, Israel.”This may help direct conservation efforts undertaken in designing future marine reserves and pre-planned artificial reefs.”Dr. Shashar and his team surveyed 295 divers to evaluate their willingness to pay for improving various elements of a coral reef. They were shown a series of photographs of the BGU-created Tamar Reef with varied densities and compositions of fish and coral species.The researchers focused on the overall aesthetic value of each component, but also how divers’ aesthetic preferences compare with scientific biodiversity attributes that might be of interest for conservation purposes.The artificial reef project is a collaboration between Israelis and Jordanians to restore the local Gulf reef culture. The Tamar Reef was the first of four reefs installed in the Red Sea. Students and faculty from both countries work together in studying the artificial reef and how it affects the marine ecology in the area.Special coral nurseries were developed to augment coral diversity. Small fragments developed into large corals and were planted on the artificial reefs.”One of the nurseries developed into an entirely new ecosystem of a floating coral reef with all types of fish; we even filmed a turtle stopping by to feed,” Shashar explains.”We are not just studying biodiversity but helping to reestablish fish and marine life that has been depleted in the Gulf.”The study was partly supported by the US-AID MERC program under grant number TA-MOU-05-M25-069 and by the Halperin and the Schechter foundations.

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Global investigation reveals true scale of ocean warming

Aug. 4, 2013 — Warming oceans are causing marine species to change breeding times and shift homes with expected substantial consequences for the broader marine landscape, according to a new global study.The three-year research project, funded by the National Centre for Ecological Analysis and Synthesis in California, has shown widespread systemic shifts in measures such as distribution of species and phenology — the timing of nature’s calendar — on a scale comparable to or greater than those observed on land.The report, Global imprint of climate change on marine life, will form part of the Intergovernmental Panel for Climate Change Assessment Report due for publication in 2014, and is published in this month’s Nature Climate Change. It was undertaken by eminent scientists at 17 institutions across the world, including the University of Queensland, Plymouth University, Aberystwyth University, and the Scottish Association for Marine Science (SAMS).One of the lead authors of the report, Professor Camille Parmesan, National Marine Aquarium Chair in Public Understanding of Oceans and Human Health within Plymouth University’s Marine Institute, said the study offered a “very simple, but important message.”Professor Parmesan said: “This is the first comprehensive documentation of what is happening in our marine systems in relation to climate change. What it reveals is that the changes that are occurring on land are being matched by the oceans. And far from being a buffer and displaying more minor changes, what we’re seeing is a far stronger response from the oceans.”The research team assembled a large database of 1,735 changes in marine life from the global peer-reviewed literature which helped them investigate impacts of climate change. The team found that 81% of changes were in a direction consistent with climate change.The evidence showed that the leading edge or ‘front line’ of some marine species, such as phytoplankton, zooplankton and bony fish, is moving towards the poles at the average rate of 72km per decade, which is considerably faster than the terrestrial average of 6km per decade — and this despite the fact that sea surface temperatures are warming three times slower than land temperatures.They also found that spring phenology in the oceans had advanced by more than four days, nearly twice the figure for phenological advancement on land. The strength of response varied among species, but again, the research showed the greatest response in invertebrate zooplankton and larval bony fish, up to 11 days in advancement.Professor Mike Burrows at SAMS said: “Most of the effects we saw were as expected from changes in climate. So, most shifts in the distributions of, say, fishes and corals, were towards the poles, and most events in springtime, like spawning, were earlier.”Some of the most convincing evidence that climate change is the primary driver behind the observed changes could be found in footprints that showed, for example, opposing responses in warm-water and cold-water species within a community; and similar responses from discrete populations at the same range edge.Dr Pippa Moore, Lecturer in Aquatic Biology from Aberystwyth University, said: “Our research has shown that a wide range of marine organisms, which inhabit the intertidal to the deep-sea, and are found from the poles to the tropics, have responded to recent climate change by changing their distribution, phenology or demography.”These results highlight the urgent need for governments around the globe to develop adaptive management plans to ensure the continued sustainability of the world’s oceans and the goods and services they provide to human society.”

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Large Gulf dead zone, but smaller than predicted

July 29, 2013 — NOAA-supported scientists found a large Gulf of Mexico oxygen-free or hypoxic “dead” zone, but not as large as had been predicted. Measuring 5,840 square miles, an area the size of Connecticut, the 2013 Gulf dead zone indicates nutrients from the Mississippi River watershed are continuing to affect the nation’s commercial and recreational marine resources in the Gulf.”A near-record area was expected because of wet spring conditions in the Mississippi watershed and the resultant high river flows which deliver large amounts of nutrients,” said Nancy Rabalais, Ph.D. executive director of the Louisiana Universities Marine Consortium (LUMCON), who led the July 21-28 survey cruise. “But nature’s wind-mixing events and winds forcing the mass of low oxygen water towards the east resulted in a slightly above average bottom footprint.”Hypoxia is fueled by nutrient runoff from agricultural and other human activities in the watershed. These nutrients stimulate an overgrowth of algae that sinks, decomposes and consumes most of the oxygen needed to support life. Normally the low or no oxygen area is found closer to the Gulf floor as the decaying algae settle towards the bottom. This year researchers found many areas across the Gulf where oxygen conditions were severely low at the bottom and animals normally found at the seabed were swimming at the surface.Graph showing historical hypoxia trends.This is in contrast to 2012, when drought conditions resulted in the fourth smallest dead zones on record, measuring 2,889 square miles, an area slightly larger than Delaware. The largest previous dead zone was in 2002, encompassing 8,481 square miles. The smallest recorded dead zone measured 15 square miles in 1988. The average size of the dead zone over the past five years has been 5,176 square miles, more than twice the 1,900 square mile goal set by the Gulf of Mexico / Mississippi River Watershed Nutrient Task Force in 2001 and reaffirmed in 2008.On June 18, NOAA-sponsored forecast models developed by Donald Scavia, Ph.D., University of Michigan, and R. …

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New genetic cause of pulmonary hypertension identified

July 24, 2013 — Columbia University Medical Center (CUMC) scientists have identified new genetic mutations that can cause pulmonary arterial hypertension (PAH), a rare fatal disease characterized by high blood pressure in the lungs. The mutations, found in the gene KCNK3, appear to affect potassium channels in the pulmonary artery, a mechanism not previously linked to the condition. Cell culture studies showed that the mutations’ effects could be reversed with a drug compound known as a phospholipase inhibitor.The study was published today in the online edition of the New England Journal of Medicine.”The most exciting thing about our study is not that we’ve identified a new gene involved in pulmonary hypertension, but that we’ve found a drug that can ‘rescue’ some mutations,” said co-senior author Wendy K. Chung, MD, PhD, associate professor of pediatrics and medicine at CUMC. “In genetics, it’s common to identify a gene that is the source of a disease. However, it’s relatively rare to find potential treatments for genetic diseases.”PAH is a progressive disorder characterized by abnormally high blood pressure in the pulmonary artery, which reduces blood flow from the right side of the heart to the lungs. The heart can compensate by pumping harder, but over time this can weaken the heart muscle and lead to right-sided heart failure. Common symptoms of PAH include shortness of breath, dizziness, and fainting. About 1,000 new cases are diagnosed in the United States each year. The disorder is twice as common in females as in males. …

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