[MARINE_BIOLOGY_INTERNATIONAL] Coral Reef Thriving in Sediment-Laden Waters


Exeter, UK — Rapid rates of coral reef growth have been identified in sediment-laden marine environments, conditions previously believed to be detrimental to reef growth. A new study has established that Middle Reef -- part of Australia's iconic Great Barrier Reef -- has grown more rapidly than many other reefs in areas with lower levels of sediment stress. Led by the University of Exeter, the study by an international team of scientists is published August 1, 2012 in the journal Geology.

Middle Reef is located just 4 km off the mainland coast near Townsville, Australia, on the inner Great Barrier Reef shelf. Unlike the clear waters in which most reefs grow, Middle Reef grows in water that is persistently 'muddy'. The sediment comes from waves churning up the muddy sea floor and from seasonal river flood plumes. The Queensland coast has changed significantly since European settlement, with natural vegetation cleared for agricultural use increasing sediment runoff. High levels of sediment result in poor water quality, which is believed to have a detrimental effect on marine biodiversity.

The research team collected cores through the structure of Middle Reef to analyze how it had grown. They used radiocarbon dating to map out the precise growth rate of the reef. Results show that the reef started to grow only about 700 years ago but that it has subsequently grown rapidly towards sea level at rates averaging nearly 1 cm per year.

These rates are significantly higher than those measured on most clear water reefs on the Great Barrier Reef and elsewhere. Most intriguingly, the periods of most rapid growth -- averaging 1.3 cm a year -- occurred when the accumulation rates of land-derived sediment within the reef structure were also at their peak. They discovered that, while the reef faced high sediment levels after the European settlers arrived in the 1800s, these same conditions were also part of the long-term environmental regime under which the reef grew.

Although there is evidence that other reefs have suffered degradation from high levels of sediment, these findings suggest that in some cases reefs can adapt to these conditions and thrive. For Middle Reef, rapid rates of vertical reef growth have, paradoxically, probably been aided by the high sedimentation rates. The team believe this is because the accumulating sediment rapidly covers the coral skeletons after their death, preventing their destruction by fish, urchins and other biological eroders, thus promoting coral framework preservation and rapid reef growth.

Professor Chris Perry of Geography at the University of Exeter said: "Our research challenges the long-held assumption that high sedimentation rates are necessarily bad news in terms of coral reef growth. It is exciting to discover that Middle Reef has in fact thrived in these unpromising conditions. It is, however, important to remain cautious when considering what this means for other reefs. Middle Reef includes corals adapted to deal with high sedimentation and low light conditions. Other reefs where corals and various other reef organisms are less well adapted may not do so well if sediment inputs increased.

"Our research calls for a rethink on some of the classic models of reef growth. At a time when these delicate and unique ecosystems are under threat from climate change and ocean acidification, a view endorsed in a recent consensus statement from many of the World's coral reef scientists, it is more important than ever that we understand how, when and where reefs can grow and thrive."

This study was conducted by a team from the University of Exeter (UK), James Cook University, Townsville, Queensland (Australia), and the NERC Radiocarbon Laboratory, Scotland (UK). It was funded by the Leverhulme Trust and Natural Environment Research Council (NERC).

Reef facts

•A coral reef is made up of thin layers of calcium carbonate (limestone) secreted over thousands of years by billions of tiny soft bodied animals called coral polyps.

•Coral reefs are the world's most diverse marine ecosystems and are home to twenty-five percent of known marine species, including 4,000 species of fish, 700 species of coral and thousands of other plants and animals.

•Coral reefs have been on the planet for over 400 million years.

•The largest coral reef is the Great Barrier Reef, which stretches along the northeast coast of Australia, from the northern tip of Queensland, to just north of Bundaberg. At 2,300km long, it is the largest natural feature on Earth.

•Coral reefs occupy less than one quarter of one percent of Earth's marine environment, yet they are home to more than a quarter of all known fish species.

•As well as supporting huge tourist industries, coral reefs protect shorelines from erosion and storm damage.

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A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>

Date: Thu 19 Jul 2012
Source: Sciencedaily.com [edited]

A Simon Fraser University (SFU) fish-population statistician, working in collaboration with non-government organization (NGO) scientists, has uncovered evidence of a potentially deadly virus in a freshwater sport fish in British Columbia.

SFU professor Rick Routledge and Stan Proboszcz, a fisheries biologist at the Watershed Watch Salmon Society, have found evidence of the piscine reovirus (PRV) in cutthroat trout caught in Cultus Lake.

Tests conducted by, Fred Kibenge, a virology professor at the Atlantic Veterinary College in Prince Edward Island, Canada, found evidence of the virus in 13 of 15 sampled fish. Follow-up analyses further confirmed the virus's presence in these fish and identified their genetic sequencing as 99 per cent identical to Norwegian strains.

The virus has been scientifically linked to heart and skeletal muscle inflammation (HSMI), a disease that has reportedly become widespread in Norwegian salmon farms and can kill up to 20 per cent of infected fish.

Routledge believes this first ever discovery of PRV in a B.C.
freshwater sport fish indicates the virus could be prevalent in B.C.

Many Canadian scientists and interest groups are concerned that B.C.
salmon farms pose a serious risk to wild Pacific salmon. Scientists in other countries have specifically raised concerns about the spread of PRV from farms to wild salmon.

"If PRV has been found in a Cultus Lake sport fish it could be contributing to the failure of the lake's sockeye population to return in abundance," says Routledge.

He notes the federal government-mandated Committee on the Status of Endangered Wildlife in Canada has listed the species as endangered.

"The discovery of PRV in Cultus Lake's cutthroat trout also begs the question is it in other related species in the lake, such as rainbow trout, kokanee and Dolly Varden? This latest discovery could also mean that salmon and trout in any lake exposed to spawning salmon returning from the North Pacific must be considered at risk of infection."

Earlier this year [2012], SFU honorary degree recipient Alexandra Morton, an independent biologist who collaborates on fish research with Routledge, reported that lab tests had found PRV in Atlantic salmon sold in B.C. supermarkets.

PRV is the 2nd virus commonly associated with salmon farming that scientists say they have found in wild Pacific salmon and trout. Last fall [2011], Routledge and Morton reported positive test results for the infectious salmon anemia virus (ISAv) in sockeye salmon smolts.

Scientists testifying at the Cohen Commission Inquiry -- a federally commissioned investigation of the Fraser River's declining sockeye population -- have brought forth highly contested evidence of ISAv in other wild salmon populations, including Cultus Lake sockeye. The inquiry is scheduled to release its findings this fall.

"We discovered during the Cohen inquiry that pathogens are a major concern for B.C.'s salmon," says Craig Orr, executive director of Watershed Watch and an SFU graduate. "Our findings suggest we need to broaden our thinking and concerns for freshwater fish as well."

"There are many examples of devastating impacts of introduced pathogens in human, mammal and marine populations," adds Routledge.
"When small pox was introduced to North America it decimated the aboriginal population, which had not had any previous opportunity to build up a natural immunity to the disease. The potential for this to happen to B.C.'s highly valued Pacific salmon and trout populations must be taken seriously."

Communicated by:
ProMED-mail from HealthMap Alerts

[The 1st cases of heart and skeletal muscle inflammation (HSMI), were registered in 1999 in the Hitra/Freya area of Norway. Since then, there have been an increasing number of outbreaks along the Norwegian coast, and it was also reported in the UK and in Chile (see post 20111013.3068). Later on, the piscine reovirus (PRV) was established as the causative agent.

This is the 1st report of the disease in the Northern Pacific. This is also the 1st report in cutthroat trout (_Oncorhynchus clarkii_). There is no mention of any pathological finding in this report, just the diagnosis of the virus. Usually, no external lesions are recognized.

A map of the affected area can be accessed at <http://healthmap.org/r/2Ym4>. - Mod.PMB]

[see also:
Infectious hematopoietic necrosis, salmon - USA: (WA)
Infectious hematopoietic necrosis - Canada: (BC) 20120518.1137106
Heart and skeletal muscle virus, salmon - Chile 20111013.3068 Infectious salmon anemia - Canada: (BC) Pacific, 1st rep 20111019.3120] .................................................sb/pmb/ejp/dk/ll
ProMED-mail makes every effort to verify the reports that are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held responsible for errors or omissions or held liable for any damages incurred as a result of use or reliance upon posted or archived material.

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[MARINE_BIOLOGY_INTERNATIONAL] New flu virus found in seals concerns scientists


Cornell, NY - Scientists in the United States have identified a new strain of influenza in harbour seals that could potentially impact human and animal health.

The H3N8 flu has been associated with the deaths of harbour seals in New England last year.

Researchers say the virus may have evolved from a type that had been circulating in birds.

They say the discovery highlights the potential for pandemic flu to emerge from unexpected sources.

Researchers were puzzled by the mysterious deaths from pneumonia of 162 harbour seals around the coast of New England last year.

Autopsies on five of the marine mammals indicate that they died from a type of H3N8 influenza A virus that is closely related to a strain circulating in North American birds since 2002.

The scientists say this flu has evolved to live in mammals and has mutated to make it more transmissable and more likely to cause severe symptoms. The virus also has the ability to target a protein found in the human respiratory tract.

Dr Anne Moscona of Weill Cornell Medical College in New York City edited the report and says that the new virus is a worry.

"There is a concern that we have a new mammalian-transmissable virus to which humans haven't yet been exposed. It's a combination we haven't seen in disease before."

While flu viruses have turned up in seals before, the researchers say this new virus may represent the first sighting of a new group with the potential to persist and move between species. The scientists had not considered that a bird flu infection could jump species to seals.

They argue that this highlights the fact that a pandemic influenza could emerge from a number of different routes.

"Flu could emerge from anywhere," said Dr Moscona, "and our readiness has to be much better than we previously realised. We need to be very nimble in our ability to identify and understand the potential risks posed by new viruses from unexpected sources."

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[MARINE_BIOLOGY_INTERNATIONAL] Man injured off Massachusetts shore; authorities suspect shark bite


Cape Cod, MA - A man who suffered lacerations to his legs while in the water at a Massachusetts beach Monday apparently was bitten by a shark, authorities said.

"It looked like a shark bite to me," Truro, Massachusetts, Fire Chief Brian Davis said of the incident at nearby Ballston Beach. "Witnesses said they saw (a) fin. They saw him go under water. He was hollering for help."

The man suffered non-life-threatening injuries on the lower part of both legs, Davis said. The man was conscious and able to speak to first-responders before being taken to a Cape Cod hospital.

Davis said the man was less than 25 yards from shore when he was injured.

If it was a shark, "I've never seen that, not that close to shore," Davis said.

The beach remained open, but Davis said National Seashore personnel would post a sign warning beachgoers to beware of sharks.

He also said there were seals in the area at the time of the incident, and the seals may have been a lure to a shark.

Greg Skomal, a marine biologist for the Massachusetts Division of Marine Fisheries, told CNN recently that more great white sharks are being seen off the coast of Cape Cod each year.

"As we've allowed seal populations to rebound over the course of the last four decades, I believe that they've now hit threshold levels that are drawing these sharks close to shore," Skomal said.

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[MARINE_BIOLOGY_INTERNATIONAL] Propeller-Slashed Whale Shark Highlights Ecotourism Danger


Cebu, PHILIPPINES = A whale shark nicknamed Fermin who has become a popular tourist attraction in the Philippines has been slashed across the face by a boat propeller, marine biologists report.

The gentle giant — whale sharks can grown more than 40 feet (12 meters) long but eat mostly tiny plankton — is a common sight in the tourist area in Tan-awan, Oslob, a resort town in Cebu. In this area of ocean, boat operators are allowed to feed whale sharks, bringing them near their boats so tourists can see the enormous fish close up.

The practice is a popular one, but marine biologists are concerned. Not only does feeding sharks teach them to associate boats with free meals, said Samantha Craven, a scientist with the Philippines Large Marine Vertebrates Project, it also seems to dissuade the sharks from their natural migrations.

"If these sharks reach sexual maturity and don't migrate to breeding grounds, they are effectively removed from the population and would no longer be adding to the numbers of genetic diversity of their species, which is listed as 'vulnerable to extinction' by the IUCN [International Union for Conservation of Nature]," Craven told LiveScience. [Gallery: The Mysterious Lives of Whale Sharks]

Fermin is one of six whale sharks that has been feeding from the tourist boats nearly daily since late March, according to the Large Marine Vertebrates Project. The group, part of the nongovernmental organization Physalus, is the only one doing research in this area of the ocean.

Most days, a dozen or more sharks show up, Craven said, but Fermin is one of the most regular boat visitors. Between July 17 and July 19, though, Fermin disappeared. When he returned on July 20, his face was scarred with 11 deep cuts, one right across his left eye.

Whale sharks are vulnerable to propeller cuts because they're difficult to see when they swim just below the surface, Craven said. But most whale sharks that have been hit show scars on their backs or fins, indicating they've been run over. Fermin's injuries are different.

"Fermin's scars are at the front of his face, indicating contact was made head-on, as if he actively approached the boat," Craven said. [See images of Fermin's Injuries]

The grisly wounds likely came from a small propeller boat. No motor boats are allowed within the Tan-awan feeding area, and it is not clear where Fermin had his run-in. It's likely, however, that he approached a boat looking for food and came away with an injury instead.

The whale sharks that feed at Tan-awan all sport odd calluses around their mouths where they rub against the boats as fishermen drop shrimp meals into the water, Craven said. But recently, more troubling marks have been showing up.

"Since June, we have seen an increase in smaller propeller scars on the regular sharks," Craven said. "None as severe as Fermin, but I worry that it is a matter of time."

Strict rules govern the interactions between humans and sharks in the Tan-awan feeding area. No more than six tourists and four scuba divers may approach one shark at a time, and no one may touch the sharks. Only members of the local fisherman's association are allowed to feed the animals.

The rules are good ones, Craven said, but they're broken "on a daily basis." The situation pits conservation against education and tourism dollars.

"I do believe that increased education and awareness about whale sharks is important, but this is a high price to pay, when more sustainable options are already proven," Craven said. "Even if there was a way to feed the sharks without creating an association of food with boats and people, we are still preventing them from migrating."

Whale shark researcher Jennifer Schmidt, a biologist at the University of Illinois at Chicago, said she felt "sick to her stomach" when she saw the photographs of Fermin's injuries. Properly regulated ecotourism that allows divers to swim alongside naturally feeding sharks doesn't seem to disrupt these threatened animals' behavior, Schmidt said. But feeding the sharks appears to be a recipe for disaster.

"I was in Oslob in April, and I saw the situation there — boats, many boats, and
sharks and swimmers and even divers all in an extremely chaotic mix," Schmidt said. "It was only a matter of time before either a shark or a person was injured, and unfortunately as long as this activity continues more sharks will be injured, even killed."

Since his disappearance and injury, Fermin has returned to the feeding area almost daily, Craven said. His wounds appear to be healing, but he usually has his eye rolled back. Whale sharks commonly roll their eyes back to protect them, but Craven said it's not clear whether Fermin is rolling back his eye because of pain or because scar tissue is hindering his ability to move his eye muscles.

"I think we have to wait to see how the wounds heal, and see how the eye is over the next two weeks before we will know more," Craven said.

The popularity of Tan-awan's whale shark feedings has spurred the nearby town of Moalboal to look into allowing similar interactions in their stretch of coastline. One Philippine senator has proposed banning whale shark feeding nationally, Craven said, but it is uncertain if it will be approved.

"I think this industry is so lucrative that one shark with a bad propeller cut is not enough to stop it locally," Craven said. "It will only stop if there is regulation from national law, coupled with education on the ground as to why it is bad, and what alternative activities can be run."

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[MARINE_BIOLOGY_INTERNATIONAL] Humpback Whales Staying in Antarctic Bays Later Into Autumn


Durham, NC — Large numbers of humpback whales are remaining in bays along the Western Antarctic Peninsula to feast on krill late into the austral autumn, long after their annual migrations to distant breeding grounds were believed to begin, according to a new Duke University study.

The study, published July 30 in the journal Endangered Species Research, provides the first density estimates for these whales in both open and enclosed habitats along the peninsula in late autumn.

It suggests that the little-studied bays are much more important late-season feeding grounds for humpback whales than scientists previously thought. It also highlights changes that are occurring in the region in response to the increasingly delayed arrival and reduced extent of annual winter sea ice cover, associated with rapid climate change.

"The old dogma is that by late autumn, the ice is heading in and the whales have headed out. But 70 percent of our surveying took place in waters with no ice, and we detected 371 groups of humpback whales over a 654-kilometer survey area, with density estimates of up to 1.75 whales per square kilometer," said David W. Johnston, research scientist at Duke's Nicholas School of the Environment and lead author of the paper.

At that density, Johnston said, "if you were to walk to the bridge of a ship and look around, you'd spot two whales within 500 meters of the boat. That's higher than anyone expected."

The scientists found the highest densities of whales in narrow, enclosed sections of Wilhelmina Bay, Andvord Bay and the Errera Channel. They found the lowest densities -- as low as 0.02 whales per square kilometer -- in the open water of the adjacent Gerlache Strait, which separates the Palmer Archipelago from the Western Antarctic Peninsula.

They conducted the study aboard the National Science Foundation (NSF) research vessel Laurence M. Gould in late April through early June of 2009. NSF funded the study.

Johnston's co-authors are Ari S. Friedlaender, research scientist; Andrew J. Read, Rachel Carson Associate Professor of Marine Conservation Biology; and Douglas P. Nowacek, Repass-Rodgers University Associate Professor of Marine Conservation Technology. All four are stationed at the Duke University Marine Laboratory. Nowacek holds a joint appointment as associate professor of electrical and computer engineering at Duke's Pratt School of Engineering.

Scientists have long known the waters around the Western Antarctic Peninsula are important foraging grounds for humpback whales that feed on swarms of shrimp-like krill there, but previous studies have been conducted earlier in the season or in open waters farther from land.

"Establishing the autumn density of humpback whales in the inshore regions of the Western Antarctic Peninsula is crucial for understanding the role they play in this rapidly changing ecosystem," said Friedlaender. "Our results provide a new perspective on the magnitude of predator-prey relationships in the region as the Antarctic winter sets in.

Being the first to estimate densities in the peninsula's narrow in-shore waters was a challenge, Johnston said, because the line-transect techniques and distance sampling methods scientists traditionally use for this type of study weren't well suited to the bays' tight quarters, tricky currents and jutting shorelines.

"We had no idea that the whales were going to be packed up in these narrow channeles and passages. We had to think on our feet a bit and use alternative sampling approaches and incorporate data from other portions of the project," he said. For instance, data collected from tagging the whales and tracking their underwater movements turned out to be inordinately useful for estimating densities, too.

"Once we knew their dive behaviors, we could establish how likely it was that we might miss them as we were traveling along the surface of the water," Johnston said. "That's not something we would have been able to do using only the traditional methods."

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[MARINE_BIOLOGY_INTERNATIONAL] Massive gator nest found in Everglades City


Massive gator nest found in Everglades City

Jul 30, 2012 1:58 PM EDT


Wooten's Airboat Tours has uncovered a massive gator nest in Everglades City.

"(It's) a good size nest average two or three feet tall…inside the center of the nest is a tiny cubby hole she's dug out and deposited 30 or 40 eggs," said "Gator" John of Wooten's Everglade Airboat Tours.

While the nest is impressive on its own, it's the mother gator that's catching their attention.

The mother gator has been able to defend her home despite her limitations.

"The front tip of her jaw is missing. The lower jaw front piece, lower flap, is barely hanging there with her teeth fully exposed," "Gator" John explained.

NBC News

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[MARINE_BIOLOGY_INTERNATIONAL] A whale of a hearing system


New York, NY - Kina, a false killer whale, was the focus of a study about how marine mammals hear. A group of scientists led by marine biologist Paul Nachtigall discovered whales can "close" their ears, decreasing their sensitivity to loud noises underwater.

Scientists have long known that man-made, underwater noises – from engines, sonars, weapons testing, and such industrial tools as air guns used in oil and gas exploration – are deafening whales and other sea mammals. The Navy estimates that loud booms from just its underwater listening devices, mainly sonar, result in temporary or permanent hearing loss for more than a quarter-million sea creatures every year, a number that is rising.

Now, scientists have discovered that whales can decrease the sensitivity of their hearing to protect their ears from loud noise. Humans tend to do this with index fingers; scientists haven't pinpointed how whales do it, but they have seen the first evidence of the behavior.

"It's equivalent to plugging your ears when a jet flies over," said Paul E. Nachtigall, a marine biologist at the University of Hawaii who led the discovery team. "It's like a volume control."
The finding, while preliminary, is already raising hopes for the development of warning signals that would alert whales, dolphins and other sea mammals to auditory danger.

Peter Madsen, a professor of marine biology at Aarhus University in Denmark, said he applauded the Hawaiian team for its "elegant study" and the promise of innovative ways of "getting at some of the noise problems." But he cautioned against letting the discovery slow global efforts to reduce the oceanic roar, which would aid the beleaguered sea mammals more directly.

The noise threat arises because of the basic properties of seawater. Typically, light can travel for hundreds of feet through ocean water before diminishing to nothingness. But sound can travel for hundreds of miles.

The world's oceans have been getting noisier as companies and governments expand their undersea activities. Researchers have linked the growing racket to deafness, tissue damage, mass strandings and disorientation in creatures that rely on hearing to navigate, find food and care for their young. The danger has long been a political football.

In 2008, the Supreme Court heard a lawsuit by the National Resources Defense Council against the Navy over ocean noise; the court ruled that naval vessels had the right to test sonar systems for hunting submarines. But environmentalists saw a tacit victory in getting the nation's highest court even to consider the health of sea mammals in a debate over national security.

The latest development took place at a research facility off Oahu – at an island where the opening shots of "Gilligan's Island" were filmed. Scientists there are studying how dolphins and toothed whales hear. In nature, the mammals emit sounds and listen for returning echoes in a sensory behavior known as echolocation. In captivity, scientists taught the creatures to wear suction-cup electrodes, which revealed the patterns of brainwaves involved in hearing.

The discovery came in steps. First, Nachtigall and his team found that the animals could adjust their hearing in response to their own loud sounds of echolocation, mainly sharp clicks. The scientists then wondered if they could also protect their ears from incoming blasts.
The team focused on a false killer whale named Kina and sought to teach her a conditioned behavior similar to how Pavlov taught dogs to salivate upon hearing a bell.

First, the scientists played a gentle tone repeatedly. Then they followed the gentle pulse with a loud sound. After a few trials, the warning signal alone caused Kina to decrease the sensitivity of her hearing.

"It shows promise as a way to mitigate the effects of loud sounds," said Nachtigall, founding director of the Marine Mammal Research Program at the University of Hawaii. "People are generally very excited about it."

In May, Nachtigall and his colleagues presented the findings to acoustic scientists and groups meeting in Hong Kong, including the Acoustical Society of America. The team cited the protective deafening as a potential way to help sea mammals cope with noisy blasts from naval sonars, civilian air guns and other equipment.
In the future, the team plans to expand the research to other species in captivity and ultimately to animals in the wild.

"We have a problem in the world," Nachtigall said of the oceanic roar. "And we think the animals can learn this response very rapidly."
Scientists unconnected to the mammal research called it important.

"It's a big deal," said Vincent M. Janik, a prominent marine biologist at the University of St. Andrews in Scotland. In an email, he said it revealed a rare ability among the planet's creatures.
Carl Safina, president of the Blue Ocean Institute, a conservation group in Cold Spring Harbor, N.Y., called the discovery a potential window into what sea mammals may already do on some occasions to protect their hearing.

"I've sometimes wondered why these high intensity sounds don't cause problems all the time," he said in an interview. "Maybe it's that, once the animals hear something very loud, they can adjust their hearing – dial it down and protect themselves."

Scientists say the extraordinary hearing of sea mammals evolved to compensate for poor visibility beneath the waves and to take advantage of the unique qualities of seawater. Sound travels five times faster than in air and undergoes far less diminishment.
The heads of whales and dolphins are mazes of resonant chambers and acoustic lenses that give the animals not only extraordinary hearing but complex voices. The distinctive songs of humpback whales appear to be sung exclusively by males seeking mates.

In recent decades, scientists have linked the human cacophony to reductions in mammalian vocalization, which suggests declines in foraging and breeding. And the problem is poised to get worse: In May, the Navy disclosed draft environmental impact statements (Atlantic and Pacific operations) that said planned expansions could raise the annual hearing losses among sea mammals to more than 1 million.

Zak Smith, a lawyer with the Natural Resources Defense Council, recently called the new estimates "staggering." A question of science, Nachtigall said, is whether the levels of protective deafening found in Kina can be increased. The team plans to study the auditory response in such species as bottlenose dolphins and beluga whales before trying it on wild populations.

The big political hurdle is financing, he said. Federal support for the sea mammal research has declined in recent years, and industry is only starting to show interest in the finding.

"I'm pulling in money where I can," he remarked. Nachtigall said the research was costly because sea mammals need high levels of care.
But he called it revealing and rewarding. "When it comes to whales and sound," Nachtigall said, "we're just starting to understand."

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[MARINE_BIOLOGY_INTERNATIONAL] Divided dolphin societies merge 'for first time'


Sydney, NSW - Two become one: the unification of these two socially distinct groups of bottlenose dolphin demonstrates the intelligence and social adaptability of the species.

A unique social division among a population of bottlenose dolphins in Australia's Moreton Bay has ended, according to a new study. The dolphins lived as two distinct groups that rarely interacted, one of which foraged on trawler bycatch.

But scientists think that a ban on fishing boats from key areas has brought the two groups together. They believe these socially flexible mammals have united to hunt for new food sources. The findings are published in the journal Animal Behaviour.

Bottlenose dolphins have large brains and quickly learn new behaviours. Using a wide range of sounds to communicate with other members of the group, or "pod", they have been observed showing remarkable individual and social intelligence:

The Moreton Bay dolphins were thought to be the only recorded example of a single population that consisted of groups that were not associating with each other in a split dubbed "the parting of the pods". But since the study that discovered the rift, trawlers have been banned from designated areas of the bay leading to a 50% reduction in the fishing effort.

A key area of the bay to the south, where the social split was observed by the previous study, has been protected. The changes gave scientists a unique opportunity to observe the adaptability of dolphin society. The "trawler" dolphins from Moreton Bay had previously fed on the bycatch from boats while the "non-trawlers" found other sources of food.

"There's never been really any experiments looking at social structure... where you can compare what it was like before and what it is like now," said Dr Ina Ansmann, marine vertebrate ecologist, University of Queensland, and the study's lead author.

Analysing how the population interacted before and after trawling meant the team could assess how the dolphins' social network had changed. "The dolphins had basically re-arranged their whole social system after trawling disappeared so they're now actually interacting again," Dr Ansmann told BBC Nature.

The scientists identified individual dolphins by the marks on their dorsal fin and recorded which animals were associating with which.

"Each dolphin has small injuries like nicks and notches, cuts and things like that on the fin so they all have a very unique looking dorsal fin." This technique meant that Dr Ansmann could observe changes in behaviour, in some cases down to the individual dolphins which had been studied in the 1990s to reveal the original division.

The "trawler" dolphins of Moreton Bay benefited from the bycatch thrown back from fishing boats "Presumably they're sharing information, co-operating and things like that." One of those males is now fully integrated into a single community.

Dolphins operate in what is called a fission-fusion society, forming groups and then splitting up to form different groups. Through complex communication and social intelligence, bottlenose dolphins often work as a team when hunting for food and Dr Ansmann believes this may be what lies behind the unification.

"When relying on natural food sources I guess it's more important for them to interact with others, or to learn from others, or to co-operate with others to get to these food sources," she said. The results suggest that a flexible social structure may be an important factor in how dolphins exploit a wide range of resources in the marine environment.

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[forensic-science] The Fitted-In Project


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[MARINE_BIOLOGY_INTERNATIONAL] Researchers Monitor 'Red Tides' in Chesapeake Bay Waters


Gloucester Point, VA — Researchers at the Virginia Institute of Marine Science continue to monitor the algal blooms that have been discoloring Chesapeake Bay waters during the last few weeks. These "red tides" occur in the lower Bay every summer, but have appeared earlier and across a wider area than in years past, likely due to last winter's warmth and this summer's heat.

Red tides are caused by dense blooms of tiny marine plants called algae that contain reddish pigment. Algae are normal components of all aquatic environments, but can produce what is known as a "harmful algal bloom" or "HAB" when they bloom in significant numbers and generate toxic byproducts. HABs can be harmful to both marine organisms and human health.

Professor Kim Reece, a member of Virginia's Harmful Algal Bloom Task Force, is the focal point for HAB research and monitoring at VIMS. Reece, fellow VIMS professor Wolfgang Vogelbein, and other colleagues at VIMS partner with representatives from the Virginia Department of Health, the Marine Resources Commission, the Department of Environmental Quality, and Old Dominion University to track the appearance of algal blooms within Virginia waters and to determine whether the bloom organisms pose any threat to marine life or human health.

There is currently no evidence of harm from the recent blooms, which were first observed in early to mid-July. Study of samples taken in the York River near VIMS' Gloucester Point campus show that they comprise dense aggregations of Cochlodinium polykrikoides, a single-celled marine dinoflagellate.

Reece says "Blooms of this and closely related species may harm oyster larvae and other marine life, and are associated with fish kills and economic loss in Japan and Korea, but we've had no reports of any of these effects in local waters this year." Fish and crab kills reported in the Bay during Cochlodinium blooms in previous years are likely due to low levels of dissolved oxygen, which are associated with blooms of many different species and occur when the algal cells die, sink, and decay.

Virginia residents who have observed a patch of water that is colored red or mahogany and are concerned should contact Virginia's toll-free Harmful Algal Bloom hotline at (888) 238-6154.

Algal blooms are not uncommon in lower Chesapeake Bay during the spring and summer. Algae respond to the same conditions that encourage plant growth on land, and thus are most likely to form blooms when waters are warm and nutrient rich. Excess nutrients from farms and yards, sewage treatment plants, and the burning of fossil fuels are one of the biggest challenges facing the Bay.

"There are three main ingredients for an algal bloom," explains Reece. "Warm waters that favor rapid growth of algal cells, abundant nutrients to fertilize that growth, and wind and tidal-driven currents to confine the cells into a dense aggregation. Our recent heat and rains provide ideal conditions for bloom formation, so we'll continue to monitor whether the ongoing blooms become a cause for any concern."

Real-time monitoring of algal blooms is not an easy task, as it involves developing and applying DNA tests to rapidly identify -- from among a huge variety of mostly benign microorganisms -- the particular algal species that have been observed to produce toxins. Development of these molecular DNA assays is a prime focus of Reece's research at VIMS.

Monitoring also requires daily collection of water samples from all across lower Chesapeake Bay. Analysis of these samples at VIMS shows that Cochlodinium is currently blooming in the York, James, Elizabeth, and Lafayette rivers; Mobjack Bay; and near the mouth of the Bay in the vicinity of the Hampton Roads Bridge Tunnel.

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