Posts 1-10 of 143

Counting Sharks with the 'Chum Cam'

By: shannond | March 11th, 2012 at 11:52pm
A team of scientists, led by the Institute for Ocean Conservation Science at Stony Brook University, used video cameras to count Caribbean reef sharks (Carcharhinus perezi) inside and outside marine reserves on the Mesoamerican Barrier Reef in the Caribbean Sea. Using survey data collected from 200 baited remote underwater video (BRUV) cameras, nicknamed "chum cams," the scientists compared the relative abundance of these reef sharks in two marine reserves with those in two areas where fishing is allowed, and demonstrated that the sharks were more abundant in the reserves.

The research findings appear in the paper, "Reef sharks exhibit site-fidelity and higher relative abundance in marine reserves on the Mesoamerican Barrier Reef," published online March 8 in the journal PLoS ONE. The purpose of the study, conducted from 2005 through 2010, was to test the hypothesis that carcharhinid shark species, which include requiem and whaler sharks, are more abundant inside no-take marine reserves where fishing for sharks and their prey is prohibited. The authors tested the hypothesis by using BRUV surveys to determine the reef sharks' numbers, and combined these results with acoustic monitoring to measure their site fidelity (remaining within the same local area) in Glover's Reef Marine Reserve, Caye Caulker Marine Reserve, and two reefs where fishing is allowed, all located in Belize.

"Although we know that relatively sedentary reef fish and lobsters benefit from marine reserves, this study now presents visual proof that large, active sharks are also dramatically more abundant inside these protected areas too," said Mark Bond, lead author and doctoral student at Stony Brook University. "Nearly four times as many chum cam deployments in the marine reserves recorded reef sharks than on similar fished reefs. These areas provide the sharks and other coral reef species a respite from fishing, which means decreased fishing mortality for the sharks and more prey for them to eat."

The video cameras were enclosed in protective housing, and placed on the sea floor with small bait-filled cages positioned in front of them. Sharks, attracted by the smell of the bait, swam to the cameras, which allowed the research team to record, count, and compare shark populations in the marine reserves to those in the areas where fishing is permitted, at no stress to the sharks. In addition to the BRUV surveys, the scientists fitted 34 reef sharks with acoustic transmitters, and tracked their movements, using moored underwater listening stations. They found that the sharks, both juveniles and adults, live year-round within the reserves.

"Scientists who study tigers or jaguars in the wild use camera traps to count them," said Dr. Demian Chapman, assistant professor in the School of Marine & Atmospheric Science at Stony Brook, leader of the research team and assistant director of science of the Institute for Ocean Conservation Science. "It is just as difficult to count sharks in the ocean, so we took a page from the big cat researchers' playbook and deployed baited video cameras to count the sharks. It's only fitting since these large apex predators are the 'big cats' of the sea, and like their feline counterparts, their continued existence on Earth is threatened."

Due to intense fishing, Caribbean reef sharks are listed as "Near Threatened" by the International Union for the Conservation of Nature (IUCN) but it is possible they will be upgraded to "Vulnerable" by IUCN as more data are collected. They live in the western Atlantic Ocean, ranging from Bermuda to southern Brazil, and are the only Atlantic requiem shark species that undergoes its entire life cycles within coral reef ecosystems.

"Caribbean reef sharks and other shark species around the world are threatened by overfishing," said Dr. Ellen K. Pikitch, a professor in the Stony Brook University School of Marine and Atmospheric Sciences, who co-authored the paper and is executive director of the Institute for Ocean Conservation Science. "Our study demonstrates that marine reserves can help protect shark species that live on coral reefs. Moreover, the use of underwater video monitoring provides us with an excellent tool to determine if populations are recovering and thriving inside these reserves."

"As the saying goes, a picture is worth a thousand words," said Bond. "As Caribbean nations and other countries consider developing marine reserves, chum cams can virtually transport policy makers and the public beneath the waves and show them the benefits of these protected areas."

Text and Photo by Stony Brook University

A Shark's Fin May be as Deadly as his Bite

By: shannond | February 25th, 2012 at 7:37pm
Sharks are among the most threatened of marine species worldwide due to unsustainable overfishing. They are primarily killed for their fins to fuel the growing demand for shark fin soup, which is an Asia delicacy. A new study by University of Miami (UM) scientists in the journal Marine Drugs has discovered high concentrations of BMAA in shark fins, a neurotoxin linked to neurodegenerative diseases in humans including Alzheimer's and Lou Gehrig Disease (ALS). The study suggests that consumption of shark fin soup and cartilage pills may pose a significant health risk for degenerative brain diseases.

"Shark fins are primarily derived through finning, a practice where by shark fins are removed at sea and the rest of the mutilated animal is thrown back in the water to die," said co-author Dr. Neil Hammerschlag, research assistant professor of Marine Affairs & Policy and director of the RJ Dunlap Marine Conservation Program (RJD) at UM. "Estimates suggest that fins from as many as 70 million sharks end up in soup. As a result, many shark species are on the road to extinction. Because sharks play important roles in maintaining balance in the oceans, not only is shark fin soup injurious to the marine environment, but our study suggests that it is likely harmful to the people who are consuming them."

Seven species of shark were tested for this study: blacknose, blacktip, bonnethead, bull, great hammerhead, lemon, and nurse sharks. Samples were collected from live animals in waters throughout South Florida.

"The concentrations of BMAA in the samples are a cause for concern, not only in shark fin soup, but also in dietary supplements and other forms ingested by humans," says study co-author Prof. Deborah Mash, Director of the UM Miami Brain Endowment Bank. The Bank supports basic and clinical research and holds one of the world's largest collection of postmortem human brains encompassing a wide range of neurological disorders. In 2009, Mash and her co-authors published a study in the journal Acta Neurological Scandinavica, demonstrating that patients dying with diagnoses of Alzheimer's Disease and ALS had unusually high levels of BMAA in their brains, up to 256 ng/mg, whereas normal healthy aged people had no BMAA or only trace quantities of the toxin present. "BMAA was first linked to neurodegenerative diseases in Guam, which resulted in the progressive loss of structure and function of neurons."

The shark study found a similar range and even higher BMAA in the fins tested, levels of between 144 and 1836 ng/mg of BMAA, which overlapped the levels measured in the brains of the Alzheimer's and ALS victims. Coincidentally, this level fits with the BMAA levels in fruit bats examined by Paul Cox in Guam, animals which concentrate BMAA from their diet of cycad seeds. He linked ingestion of fruit bats to the severe ALS/Parkinsonism dementia that afflicted local indigenous people.

"Not only does this work provide important information on one probable route of human exposure to BMAA, it may lead to a lowering of the demand for shark fin soup and consumption of shark products, which will aid ocean conservation efforts," added Hammerschlag.

Text by University of Miami, Rosenstiel School of Marine and Atmospheric Science Photo by Eric Cheng

The Shark Skin Advantage

By: shannond | February 14th, 2012 at 7:06pm
Streamlined sharks are legendary for their effortless swimming. George Lauder from Harvard University explains that the fish have long inspired human engineers, but more recently attention has focused on how the fish's remarkable skin boosts swimming. Coated in razor sharp tooth-like scales, called denticles, the skin is thought to behave like the dimples on a golf ball, disturbing the flow of water over the surface to reduce the drag. But something didn't quite sit right with Lauder.

"All of the shark skin studies were done on flat shark skin mimics that were held straight and immovable. But shark skin moves," recalls Lauder. So, when Masters student Johannes Oeffner joined his lab, Lauder suggested that they take a look at the fluid dynamics of shark skin and its analogues to find out how the fish's motion affects fluid flowing over the rough surface. The duo publishes its discovery that shark skin actually generates thrust to give the fish an additional boost in The Journal of Experimental Biology at http://jeb.biologists.org/.

But first the duo had to get hold of some fresh shark skin, so they went to a market in Boston where they found several large makos. Back in the lab, Oeffner carefully removed sections from a mako's skin and attached them to both sides of a rigid aluminum foil. Then he immersed the foil in a flow tank, reproduced the swimming motion of a fish by wiggling it from side to side and measured the rigid 'swimming' foil's speed by matching it with the flow of water moving in the opposite direction.

Having measured the foil's swimming speeds with intact skin -- complete with denticles -- Oeffner carefully sanded off the denticles and set the foil swimming again. However, instead of slowing down -- as the duo had expected -- the denticle-free foil speeded up. So the shark skin's denticle surface impeded the rigid swimmer. "But then we remembered our premise that the sharks aren't rigid," remembers Lauder, so how would the shark skin perform when flexing like a real fish?

Gluing two pieces of shark skin together to produce a flexible foil, Oeffner repeated the swimming experiment, and this time the denticles had a dramatic effect. The intact skin foil swam 12.3% faster than the sanded skin. The shark's rough surface improved the swimming performance spectacularly.

However, when the duo tested the swimming performance of two shark skin mimics -- a sharp-edged riblet design and the famous Speedo Fastskin FS II fabric -- they were in for a shock. Although the riblet surface improved the flexible foil's swimming speed by 7.2%, the dented surface of the Speedo fabric had no effect at all. However, Lauder points out that figure-hugging Fastskin swimming costumes probably enhance the swimmer's performance in other ways.

After proving that the denticles on shark skin significantly improve the fish's propulsion, Lauder and Oeffner were keen to find out how they affect fluid flows around the body. Returning the flexible shark skin foil to the swim tunnel, Oeffner and Lauder captured the water's swirling motion with laser light and realized that in addition to reducing drag, the skin was actively generating thrust.

"That's the number one surprise. It's not just the drag-reducing properties, but the denticles alter the structure of flow near the shark skin in a way that enhances thrust," explains Lauder. He is now keen to design physical models to see how altered denticle arrangements affect fluid flows over the skin and to build a computational model to tease apart the beneficial effects of the skin's thrust and drag reduction.

Text by Journal of Experimental Biology Photo by EPA

Shark Deaths Hit 20-year High

By: shannond | February 7th, 2012 at 7:06pm
Shark attacks in the U.S. declined in 2011, but worldwide fatalities reached a two-decade high, according to the University of Florida's International Shark Attack File report.

While the U.S. and Florida saw a five-year downturn in the number of reported unprovoked attacks, the 12 fatalities -- which all occurred outside the U.S. -- may show tourists are venturing to more remote places, said ichthyologist George Burgess, director of the file housed at the Florida Museum of Natural History on the UF campus.

"We had a number of fatalities in essentially out-of the way places, where there's not the same quantity and quality of medical attention readily available," Burgess said. "They also don't have histories of shark attacks in these regions, so there are not contingency plans in effect like there are in places such as Florida."

Seventy-five attacks occurred worldwide, close to the decade average, but the number of fatalities doubled compared with 2010. Fatalities occurred in Australia (3), Reunion (2), the Seychelles (2) and South Africa (2), with one each in Costa Rica, Kenya and New Caledonia. The average global fatality rate for the last decade was just under 7 percent, and it rose to 16 percent last year. Excluding the U.S., which had 29 shark attacks but no deaths, the international fatality rate averaged 25 percent in 2011, Burgess said.

"We've had a decade-long decline in the number of attacks and a continued decline in the fatality rate in the U.S.," Burgess said. "But last year's slight increase in non-U.S. attacks resulted in a higher death rate. One in four people who were attacked outside the U.S. died."

Florida led the U.S. with 11 of its 29 attacks. Other countries with multiple attacks include Australia (11), South Africa (5), Reunion (4), Indonesia (3) Mexico (3), Russia (3), Seychelles (2) and Brazil (2). While the higher number of fatalities worldwide came as a surprise, the drop in the number of U.S. attacks follows a 10-year decline, Burgess said.

"It's more than coincidence that we've had this drop over this last decade," Burgess said. "The fact is, that's a downward trend, and there has to be a cause for that. People might argue there's less sharks, but since the late 1990s, populations have begun a slow recovery. By contrast, the number of attacks in the United States and Florida suggests there's been a reduced use of these waters."

Florida's attacks historically lead the U.S., and as a high aquatic recreation area, especially for surfers, Volusia County leads the state. In 2011, Volusia County again led the state with six attacks, but it was the lowest since 2004 (3).

"It's a good news/bad news situation," Burgess said. "From the U.S. perspective, things have never been better, our attack and fatality rates continue to decline. But if it's a reflection of the downturn in the economy, it might suggest that other areas have made a real push to get into the tourism market."

The next step to reducing the number of fatalities is creating emergency plans for these alternative areas in the future, said Burgess, who has been invited to work on developing a response plan in Reunion Island this spring.

"Ironically, in this very foreign environment that has animals and plants that can do us harm, we often don't seem to exhibit any concern at all, we just jump in," Burgess said.

Surfers were the most affected group, accounting for about 60 percent of unprovoked attacks, largely due to the provocative nature of the activity. Swimmers experienced 35 percent of attacks, followed by divers, with about 5 percent.

"When you're inside the water, there's much less chance of sharks making a mistake because both parties can see each other," Burgess said. "Surfing involves a lot of swimming, kicking and splashing."

Despite the number of deaths being higher than other years, people should remember how much of a threat humans are to sharks, Burgess said. With worldwide over-fishing, especially to meet demands for flesh and fins used in shark fin soup, an expensive Asian delicacy, humans pose a greater threat to elasmobranchs (sharks, skates and rays) than sharks do to humans.

"We're killing 30 to 70 million sharks per year in fisheries -- who's killing who?" Burgess said. "The reality is that the sea is actually a pretty benign environment, or else we'd be measuring injuries in the thousands or millions per year."

The 2011 Worldwide Shark Attack Summary may be viewed online.

Text by University of Florida Photo by NOAA

Humpbacks Sing Different Tunes

By: shannond | February 7th, 2012 at 7:01pm
A recently published study by the Wildlife Conservation Society and others reveals that humpback whales on both sides of the southern Indian Ocean are singing different tunes, unusual since humpbacks in the same ocean basin usually all sing very similar songs.

The results of the study -- conducted by researchers from WCS, Columbia University, and Australia -- contradict previous humpback whale song comparisons. Generally, when song from populations in the same ocean basins are compared, researchers find that the songs contain similar parts or "themes." The differences in song between the Indian Ocean humpback populations most likely indicate a limited exchange between the two regions and may shed new light on how whale culture spreads.

The paper appears in the January edition of Marine Mammal Science and is available on the journal's website. The authors of the study include: Anita Murray, formerly of the Wildlife Conservation Society and Columbia University ; Salvatore Cerchio, Yvette Razafindrakoto, and Howard Rosenbaum of the Wildlife Conservation Society; Robert McCauley of Curtin University, Perth, Australia; Curt S. Jenner of the Centre for Whale Research, Fremantle, Australia; Douglas Coughran of the Department of Environment and Conservation, Perth, Australia; and Shannon McKay of the School of Life and Environmental Science, Warrnambool, Australia.

"In the Northern Hemisphere, within an ocean basin whales sing songs that are composed of the same themes. However, whales in the southern Indian Ocean are singing almost completely different songs. Songs from Madagascar and Western Australia only shared one similar theme, the rest of the themes were completely different," said lead author Anita Murray, who conducted the research while a graduate student at Columbia University and the Wildlife Conservation Society and is currently pursuing her doctorate at the University of Queensland in Australia. "The reason for this anomaly remains a mystery. It could be the influence of singing whales from other ocean basins, such as the South Pacific or Atlantic, indicating an exchange of individuals between oceans which is unique to the Southern Hemisphere."

The songs of humpback whales are generally sung by male individuals on a population's winter breeding grounds, migratory routes, and summer feeding grounds. The songs themselves are complex arrangements of parts or "themes," consisting of ascending and descending wails, moans, and shrieks that are repeated in cycles lasting up to 30 minutes. The transmission of songs between individuals from different populations is likely to occur on feeding grounds or during migration when whales from different populations mix. Or, transmission of song may occur when individual male "troubadours" travel to different breeding grounds between breeding seasons or possibly during the same breeding season.

The research team made recordings of humpback whale songs in two locations in coastal Madagascar and three locations along Western Australia during the 2006 breeding season. Research teams in both regions used hydrophones to record the songs of 19 individual whales. Overall, the authors captured more than 20 hours of whole and partial songs for visual and audio analysis. The comparison revealed few similarities between songs; of the eleven themes recorded in both regions, only one theme was shared by both populations. Due to the limited duration of the study (only one breeding season), researchers point out that continued analysis of songs in Madagascar and Australia are needed to examine the reasons for the limited similarity in repertoire.

Dr. Howard Rosenbaum, Director of WCS's Ocean Giants Program said: "These song comparisons complement our findings based on other methods, such as those from genetic analysis, to understand how whale populations interact with one another."

WCS conservationist Salvatore Cerchio added: "We have glimpsed here a snapshot of differences in repertoire between humpback whale populations of the Indian Ocean during a single season. Continued monitoring of these songs can provide us with valuable information on how whale songs are exchanged and how those channels of cultural transmission can be protected in the future."

WCS has been involved in research on humpback whales since the 1960s, when researchers from the New York Zoological Society (now the Wildlife Conservation Society) discovered that the vocalizations of humpback whales are, in fact, songs, defined as a series of themes that are repeated in cycles. For the past decade, WCS's Ocean Giants Program has conducted an extensive molecular analysis of humpback whale populations in the southern Atlantic and Indian oceans in an attempt to better define discrete populations.

The humpback whale is a baleen whale that grows up to approximately 50 feet in length. The species has distinctively long pectoral fins and a head with knobs on the top and lower jaw. The slow-swimming species was hunted commercially until the International Whaling Commission protected the species globally in 1966. Current estimates for humpback whale numbers are widely debated. While they are recovering, total population sizes may represent only a small percentage of the original global population.

Text by Wildlife Conservation Society Photo by S. Cerchio

Munching on Marine Mammals

By: shannond | January 29th, 2012 at 8:10pm
The fate of the world's great whale species commands global attention as a result of heated debate between pro and anti-whaling advocates, but the fate of smaller marine mammals is less understood, specifically because the deliberate and accidental harvesting of dolphins, porpoises, manatees and other warm-blooded aquatic denizens is rarely studied or monitored. To shed more light on the issue, researchers from the Wildlife Conservation Society and Okapi Wildlife Associates have conducted an exhaustive global study of human consumption of marine mammals using approximately 900 sources of information.

The main finding: since 1990, people in at least 114 countries have consumed one or more of at least 87 marine mammal species. In addition to this global review, Wildlife Conservation Society scientists work in remote countries around the world to assess and actively address the threat to dolphin populations with localized, applied conservation efforts.

The new global study appears in the most recent edition of Biological Conservation. The authors include: Dr. Martin D. Robards of the Wildlife Conservation Society; and Dr. Randall R. Reeves of Okapi Wildlife Associates.

"International bodies such as the International Whaling Commission were formed specifically to gauge the status of whale populations and regulate the hunting of these giants," said Robards, lead author of the new study. "These species, however, represent only a fraction of the world's diversity of marine mammals, many of which are being accidentally netted, trapped, and -- in some instances -- directly hunted without any means of tracking as to whether these harvests are sustainable."

In order to build a statistically robust picture of human consumption rates of marine mammals around the world, Robards and Reeves started with records on small fisheries focused on small whales (i.e. pilot whales), dolphins, and porpoises from 1975 and records of global marine mammal catches between 1966 and 1975. From there, the authors consulted some 900 other sources and consulted with numerous researchers and environmental managers, an exhaustive investigation that took three years to complete. The team only counted information with actual evidence of human consumption of marine mammals, omitting instances where marine mammals were caught (either intentionally or not) for fishing bait, feed for other animals, medicines, and other uses.

The list of marine mammals killed for human consumption includes obscure species such as the pygmy beaked whale, the South Asian river dolphin, the narwhal, the Chilean dolphin, the long-finned pilot whale, and Burmeister's porpoise. Seals and sea lions are on the list as well, including species such as the California sea lion and lesser known species such as the Baikal seal. The polar bear (a bear that is considered a marine mammal) also makes the list. Three species of manatee and its close relative the dugong, considered a delicacy in some parts of the world, are also widespread targets of human consumption.

Overall, the historical review reveals an escalation in the utilization of smaller cetaceans, particularly coastal and estuarine species since 1970, often caught as accidental "bycatch" in nets meant for fish and other species. Once caught, however, small cetaceans are being increasingly utilized as food in areas of food insecurity and/or poverty, what the authors call "fishing up the food chain."

"Obviously, there is a need for improved monitoring of species such as the Atlantic and Indo-Pacific humpback dolphins and other species," said Dr. Howard Rosenbaum, Director of WCS's Ocean Giants Program. "In more remote areas and a number of countries, a greater immediate need is to understand the motivations behind the consumption of marine mammals and use these insights to develop solutions to protect these iconic species that lead to more effective management and conservation."

WCS's Ocean Giants Program works in a number of seascapes of critical importance to small cetaceans in particular. These efforts are focused on the local level to address local impacts on coastal dolphin populations, providing on-the-ground practical conservation actions to compliment the global investigative work highlighted above.

In Congo, Gabon, and Madagascar, WCS conservation scientists Dr. Salvatore Cerchio and Tim Collins are conducting scientific studies to assess the status of impacted dolphin populations, and work with local communities of traditional fishermen to reduce accidental bycatch and deliberate hunting of dolphins. In these regions, the scientists are documenting a worrying trend in increased captures and use of dolphins for food, and they are sometimes also being sold in markets better known for their association with terrestrial bushmeat.

In response, Cerchio and the WCS Madagascar team have worked with local communities to establish a local conservation association composed of fishermen, local traditional laws protecting dolphins, and development of community-based whale and dolphin watching as an alternative livelihood. On the other side of the African continent, the coasts of Gabon and Congo represent one of the last strongholds for the rare Atlantic humpback dolphin. Catches by fishermen in Gabon are extremely rare, but groups of dolphins that cross the border (a finding of recent WCS work) risk capture in coastal gillnets set by artisanal fisherman. "The Atlantic humpback dolphin may well be the rarest mammal in the Congo basin region," said Tim Collins. "Unfortunately, few have ever heard of it, least of all the fisherman eating them out of existence."

Text by Wildlife Conservation Society Photo by NOAA

Is Carbon Dioxide Making Fish Crazy?

By: shannond | January 23rd, 2012 at 7:21pm
Rising human carbon dioxide emissions may be affecting the brains and central nervous system of sea fishes with serious consequences for their survival, an international scientific team has found.

Carbon dioxide concentrations predicted to occur in the ocean by the end of this century will interfere with fishes' ability to hear, smell, turn and evade predators, says Professor Philip Munday of the ARC Centre of Excellence for Coral Reef Studies and James Cook University.

"For several years our team have been testing the performance of baby coral fishes in sea water containing higher levels of dissolved CO2 -- and it is now pretty clear that they sustain significant disruption to their central nervous system, which is likely to impair their chances of survival," Prof. Munday says.

In their latest paper, published in the journal Nature Climate Change, Prof. Munday and colleagues report world-first evidence that high CO2 levels in sea water disrupts a key brain receptor in fish, causing marked changes in their behavior and sensory ability.

"We've found that elevated CO2 in the oceans can directly interfere with fish neurotransmitter functions, which poses a direct and previously unknown threat to sea life," Prof. Munday says.

Prof. Munday and his colleagues began by studying how baby clown and damsel fishes performed alongside their predators in CO2-enriched water. They found that, while the predators were somewhat affected, the baby fish suffered much higher rates of attrition.

"Our early work showed that the sense of smell of baby fish was harmed by higher CO2 in the water -- meaning they found it harder to locate a reef to settle on or detect the warning smell of a predator fish. But we suspected there was much more to it than the loss of ability to smell."

The team then examined whether fishes' sense of hearing -- used to locate and home in on reefs at night, and avoid them during the day -- was affected. "The answer is, yes it was. They were confused and no longer avoided reef sounds during the day. Being attracted to reefs during daylight would make them easy meat for predators."

Other work showed the fish also tended to lose their natural instinct to turn left or right -- an important factor in schooling behavior which also makes them more vulnerable, as lone fish are easily eaten by predators.

"All this led us to suspect it wasn't simply damage to their individual senses that was going on -- but rather, that higher levels of carbon dioxide were affecting their whole central nervous system."

The team's latest research shows that high CO2 directly stimulates a receptor in the fish brain called GABA-A, leading to a reversal in its normal function and over-excitement of certain nerve signals.

While most animals with brains have GABA-A receptors, the team considers the effects of elevated CO2 are likely to be most felt by those living in water, as they have lower blood CO2 levels normally. The main impact is likely to be felt by some crustaceans and by most fishes, especially those which use a lot of oxygen.

Prof. Munday said that around 2.3 billion tonnes of human CO2 emissions dissolve into the world's oceans every year, causing changes in the chemical environment of the water in which fish and other species live.

"We've now established it isn't simply the acidification of the oceans that is causing disruption -- as is the case with shellfish and plankton with chalky skeletons -- but the actual dissolved CO2 itself is damaging the fishes' nervous systems."

The work shows that fish with high oxygen consumption are likely to be most affected, suggesting the effects of high CO2 may impair some species worse than others -- possibly including important species targeted by the world's fishing industries.

Text and Photo by ARC Centre of Excellence in Coral Reef Studies

Can We Save the Whales by Buying Them?

By: shannond | January 15th, 2012 at 7:45pm
Every year, a group of anti-whaling nonprofit organizations that includes Greenpeace, Sea Shepherd, and the World Wildlife Fund spend, by conservative estimates, some $25 million on a variety of activities intended to end commercial whaling. And every year, commercial whaling not only continues, but grows.

Under the current, largely unregulated system, the number of whales harvested annually has doubled since the early 1990s, to about two thousand per year. Further, many populations of large whales have been severely depleted and continue to be threatened by commercial whaling.

While protests, education, lobbying and dangerous confrontations on the high seas have saved some whales, the whaling industry shows no sign of shutting down -- or slowing down.

Now, an economist and two marine scientists writing in the January 12 issue of the journal Nature suggest a new strategy that they believe could save whales by putting a price on them.

In the article, "A market approach to saving the whales," Christopher Costello and Steve Gaines, professors of economics and marine science, respectively, at the Bren School of Environmental Science & Management at the University of California, Santa Barbara, join Leah Gerber, a population ecologist and marine conservation biologist at Arizona State University, to propose a market-based solution to saving whales.

"We propose an alternative path forward that could break the deadlock: quotas that can be bought and sold, creating a market that would be economically, ecologically, and socially viable for whalers and whales alike," the authors write.

"The authors have put forth some bold, fresh thinking aimed at a barbaric practice that has become an intractable problem," said The Nature Conservancy California Executive Director Mike Sweeney.

The idea has its roots in trading markets for such air pollutants as sulfur dioxide and nitrogen oxides, which have reduced pollutants more and at a lower cost in the U.S. than resulted from traditional regulatory policy; conservation and wetland management programs, which have resulted in more than 200,000 acres of land being set aside; and individual transferable quotas, which have been successful in sustaining fisheries and fishermen in New Zealand, Iceland, and Canada.

The authors explain that the concept of auctioning off annual whale-catch quotas was suggested as early as 1982 but was never implemented, perhaps, they suggest, because whalers would have had to purchase something they had always received for free. They add that a "whale-conservation market," would be different, with "whale shares" being allocated in sustainable numbers to all members of the International Whaling Commission. Recipients could then exercise them (by harvesting their quota), hold onto them for a year, or permanently retire them. The shares would be tradable in a carefully controlled global market.

In the two most extreme scenarios, whalers could end up purchasing all the shares and harvesting whales at the established sustainable level, or conservationists might purchase all the shares, so that no whales would be harvested.

"Because conservationists could bid for quotas, whalers could profit from them even without harvesting the animals," the professors say. And while they concede that "there are multiple challenges in getting such a scheme to work, including agreeing on sustainable quotas and on how shares should be allocated," they do not see those obstacles as insurmountable.

But would whalers settle for quotas? In fact, the authors say, whaling nations have previously proposed quotas, which would legitimize their harvest. Many anti-whaling groups, on the other hand, have had a fundamental problem with setting quotas for the same reason, feeling that quotas would appear to legitimize commercial whaling.

"If quotas are set properly," the authors suggest, "transactions would reduce the number of whales harvested, quite possibly to zero, unlike existing protocols, which seem to be increasing the catches."

They conclude: "The fervent anti-whaler will be quick to argue you cannot and should not put a price on the life of a whale; a species should be protected irrespective of its economic value. But unless all nations can be convinced or forced to adopt this view, whaling will continue. It is precisely because of the lack of a real price tag in the face of different values that anti-whaling operations have had such limited success.... By placing an appropriate price tag on the life of a whale, a whale conservation market provides an immediate and tangible way to save them."

Text by University of California - Santa Barbara Photo by NOAA

Fish Mimics Octopus That Mimics Fish

By: shannond | January 6th, 2012 at 4:09pm

Nature's game of intimidation and imitation comes full circle in the waters of Indonesia, where scientists have recorded for the first time an association between the black-marble jawfish (Stalix cf. histrio) and the mimic octopus (Thaumoctopus mimicus).

Undescribed by scientists until 1998, the talented mimic octopus is known to impersonate toxic flatfish, lionfish, and even sea snakes by creatively configuring its limbs, adopting characteristic undulating movements, and displaying bold brown-and-white color patterns. Thanks to these brazen habits, it can swim in the open with relatively little fear of predators.

The jawfish, on the other hand, is a small and timid fish. It spends most of its adult life close to a sand burrow, where it will quickly retreat upon sighting a predator.

During a diving trip in Indonesia in July 2011, Godehard Kopp of the University of Gottingen, Germany, filmed an unexpected pairing between the two animals. Like a lackey clinging on to the big man on campus, the black-marble jawfish was seen closely following a mimic octopus as it moved across the sandy bottom. The jawfish had brown-and-white markings similar to the octopus, and was difficult to spot among the many arms. The octopus, for its part, did not seem to notice or care.

Kopp sent the video to Rich Ross and Luiz Rocha of the California Academy of Sciences, who identified the jawfish species. Since this association had not been recorded before, they published their observations online last month in the scientific journal Coral Reefs. The authors surmise that the jawfish hitches a ride with the octopus for protection, allowing it to venture away from its burrow to look for food -- a case of "opportunistic mimicry."

"This is a unique case in the reefs not only because the model for the jawfish is a mimic itself, but also because this is the first case of a jawfish involved in mimicry," said Dr. Luiz Rocha, assistant curator of ichthyology at the California Academy of Sciences. "Unfortunately, reefs in the Coral Triangle area of southeast Asia are rapidly declining mostly due to harmful human activities, and we may lose species involved in unique interactions like this even before we get to know them."

Text and Video by California Academy of Sciences

Where the Tsunami Debris is Going Now

By: shannond | December 29th, 2011 at 5:34pm
Debris from the tsunami that devastated Japan in March could reach the United States as early as this winter, according to predictions by NOAA scientists. However, they warn there is still a large amount of uncertainty over exactly what is still floating, where it's located, where it will go, and when it will arrive. Responders now have a challenging, if not impossible situation on their hands: How do you deal with debris that could now impact U.S. shores, but is difficult to find?

To learn more about the tsunami debris, NOAA researchers have been working with the U.S. Environmental Protection Agency, U.S. Fish and Wildlife Service, and other partners to coordinate data collection activities.

NOAA and its partners are also coordinating an interagency assessment and response plan to address the wide-range of potential scenarios and threats posed by the debris.

"We're preparing for the best and worst case scenarios -- and everything in between," says Nancy Wallace, director for NOAA's Marine Debris Program.

As the tsunami surge receded, it washed much of what was in the coastal inundation zone into the ocean. Boats, pieces of smashed buildings, appliances, and plastic, metal, and rubber objects of all shapes and sizes washed into the water -- either sinking near the shore or floating out to sea. The refuse formed large debris fields captured by satellite imagery and aerial photos of the coastal waters.

The Japanese government estimated that the tsunami generated 25 million tons of rubble, but there is no clear understanding of exactly how much debris was swept into the water nor what remained afloat.

What remains of the debris?


Nine months later, debris fields are no longer visible. Winds and ocean currents scattered items in the massive North Pacific Ocean to the point where debris is no longer visible from satellite. Vessels regularly traveling the North Pacific have reported very few sightings. Only two pieces have been clearly linked to the tsunami.

NOAA is coordinating new interagency reporting and monitoring efforts that will provide critical information on the location of the marine debris generated by the tsunami. Ships can now report significant at-sea debris sightings and individuals or groups can request shoreline monitoring guides at DisasterDebris@noaa.gov.

Where is it?

Computer models run by NOAA and University of Hawaii researchers show some debris could pass near or wash ashore in the Northwestern Hawaiian Islands (in the Papahnaumokukea Marine National Monument) as early as this winter, approach the West Coast of the United States and Canada in 2013, and circle back to the main Hawaiian Islands in 2014 through 2016.

Researchers caution that models are only predictions based on location of debris when it went into the water, combined with historical ocean currents and wind speeds.

Conditions in the ocean constantly change, and items can sink, break down, and disperse across a huge area. Because it is not known what remains in the water column nor where, scientists can't determine with certainty if any debris will wash ashore.

Worst- and Best-case Scenarios


The worst-case scenario is boats and unmanageable concentrations of other heavy objects could wash ashore in sensitive areas, damage coral reefs, or interfere with navigation in Hawaii and along the U.S. West Coast. Best case? The debris will break up, disperse and eventually degrade, sparing coastal areas.

Debris will not go away completely, even in a best-case scenario. Marine debris is an ongoing problem for Hawaii and West Coast states, where garbage and other harmful items regularly wash up on beaches, reefs and other coastal areas.

Text and Graphic by National Oceanic and Atmospheric Administration

Contributors

shannond

Blog Posts: 2436

wetsanduser4

Blog Posts: 217

wetsanduser1

Blog Posts: 67