Scubaism

How much damage can a slow big ship do? For her doctorate project, Regina Campbell-Malone of the Woods Hole Oceanographic Institution has compressed and stressed whalebone to determine just how much it can take.

“With most problems you break them down to the simplest components possible,” she explained. “You look at bone at the tissue level to see what a small bone sample will do. It turns out the shape of the whole bone doesn’t matter so much. It’s the weakest part of the bone that’s going to break.”

Applying engineering and mathematics enable her to extrapolate from that tiny lab sample to a 500-pound bone in real life. “Another project is running a model ship into a model whale on a computer,” noted Campbell-Malone. “We’ve been working on that for three years now. There is a grad student at UNH who took measurements of a specific whale and a specific ship and put these into a computer.”

That model allows a researcher to sail at different ship speeds and clip the whale at varied angles. “Those are the two ways of looking at it — at the scale of whale bone and tissue and the full scale geometry of collision,” Campbell-Malone declared.

She has taken option one. When a dead 50-foot female right whale named Stumpy washed ashore in North Carolina three years ago, she had her chance to get a bone. “We saw one-third of the animals killed by blunt trauma had broken jaws. And we’ve never seen a right whale skeleton that had a healed jawbone,” she said. “So it’s more than likely that this injury causes death.” So it was the jaw they collected.

“We did a full necropsy and brought the [493 pound] jawbone back to Woods Hole and kept it in a freezer. We pulled it out and weighed it and used a wood corer to take samples of bone. We made many samples,” recalled Campbell-Malone.

The result is the amount of stress (force per unit area) that would break the bone. What consumes her now is translating the lab data to the physical reality of the full-size jaw. The computer will match that with potential forces up to that delivered by a 300,000-ton oil tanker.

“Thinking about the worst case; maximum impact would be from a perpendicular strike. Then it depends on how fast you are going and the mass of the ship,” Campbell-Malone said.

Her bones have all been squashed. What does it take to break a right whale? Ask her come January when the analysis is done. “NOAA is looking at the first biomechanical data on whether the speed restrictions and slowing down when there are right whales around is going to help,” Campbell-Malone said. “The data are still out as to how right whales are responding, but I think the answer is yes, speed restrictions will help.”
Some believe a slow ship just means more time for a collision. But Campbell-Malone has seen a right whale avoid electronic gear trailing behind a vessel. “Given the appropriate amount of time, they can interpret the world around them and choose a course of action,” she said. “They interpret natural signals that say ‘this is a good place to eat’. They interpret sounds from other right whales a decide whether to join or avoid them. We know they have the capability of responding to stimuli. This may include vessels – the jury is still out.”

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Could dolphins, seals and herring-eating whales be far behind?

Fishermen say they are seeing more herring returning to the Gulf of Maine, where a ban on trawlers that drag nets through the water has been in effect through the summer.

Other purse seine herring fishermen, whale-watching companies and tuna fishermen are reporting similar observations. They also say they see more sea birds, dolphins, tuna and seals, which feed on herring.

Their reports contrast with what was seen a year earlier, when more trawlers, sometimes working in pairs, cut through the water dragging nets for herring. In the meantime, a ban on midwater herring trawlers has been in place in Gulf of Maine coastal waters.

The New England Fishery Management Council’s ban extends 50 to 60 miles offshore and lasts from June 1 to Sept. 30. It doesn’t affect fishing boats that use purse seine nets that encircle the fish when they come to the surface to feed at night.

The restriction was put in place in response to pressure from conservationists, tuna fishermen, lobstermen and sporting and whale watching boat companies, which said the big nets that go deeper in the water break up herring schools and disrupt their breeding behavior.

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A decade-old photograph wasn’t enough, so marine biologist Marc Hughes grabbed his chance the next time he saw the strange fish in an underwater lava tube cave off the Big Island. In a flash, he slipped the droopy mouthed, eel-like fish into a pocket of his scuba outfit.

Now, the six-inch fish is being heralded by Bishop Museum tropical fish expert John E. Randall as a new species in the genus Grammonus. Other Grammonus species are found in waters from Japan to South Asia, the Gulf of Aden and even the Mediterranean.

But Randall says Hughes’ fish, which the biologist first photographed in 1998, is a unique species. The brownish fish has fins along its rear that make it look similar to an eel, and its mouth is turned down like a grumpy old man.

Randall says he and Hughes are preparing a scientific paper on the fish in the process aimed at getting it recognized and bestowing a name on the species.

One unusual characteristic of the fish is that it gives birth to live young, like some freshwater fish, such as guppies, Randall told West Hawaii Today, which first reported the find in its Saturday edition. He said it also has a system of pores along its body that allow it to sense and slight water movement.

“It’s an interesting feature, and probably one used to detect the presence of predators and hunt for prey because it is a completely dark environment,” he said. “The fish has to rely upon its sense of movement rather than sight.” Randall said other divers have probably seen the fish but they didn’t know what to look at.

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A 16-year-old Vietnamese boy has died after being stabbed through the heart by a needlefish as he was diving for seafood in northern Vietnam, a policeman said Monday. The meter-long fish - a type of gar with a long, pointed snout - stabbed diver Duong Trong Anh in the chest as he was diving for sea cucumber, according to Ta Van Quynh, deputy police chief of Halong Bay district, 200 kilometers east of Hanoi.

The boy was in 2 meters of water when the accident happened Friday, Quynh said. The boy’s diving companions saw the fish stuck in the chest of their friend and pulled the needle-like snout out, the policeman said. “Anh died from the wound soon after,” Quynh said.

According to Quynh, the fish might have been startled by the divers and tried to swim away but accidently hit Anh with its 15-centimeter-long snout, according to the policeman. “It’s a very strange death,” the policeman said. “People may get killed by sharks, rarely by this kind of fish.” Anh’s friends brought the needlefish to the surface with his body and the family is considering burial of the fish alongside the boy, Quynh said.

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Ashψ shot this dramatic shot of bubbletip coral in Japan. Great composition. Wish I shot that!

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An unprecedented number of basking sharks were spotted off Cornwall recently. 460, in fact. Until then, the highest number seen in the area was 300. The high number has been attributed to the abundance of plankton in the area.

But one thing puzzles me. How does one go about counting a mass of constantly-moving sharks? Especially when they’re not all tagged or otherwise individually identifiable.

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Five men were arrested Thursday for illegal international trade of exotic skins and parts manufactured from sea turtles and other protected species of wildlife.

The two indictments detail 54 conspiracy, smuggling and money-laundering charges. The defendants are accused of smuggling 25 separate shipments of wildlife skins and products between Mexico and the United States between early 2005 and today. The shipments contained more than 700 tanned skins of sea turtle, caiman, python and other protected species, and well over 100 items, such as boots, belts and wallets, manufactured from the skins of those species.

The indictments allege that nearly $60,000 was paid to the Mexican suppliers and of the illegal skins and products, in addition to “crossing fees” paid to the alleged smugglers.

Arrested in Denver were Carlos Leal Barragan, of Guzman, Jalisco, Mexico; and Esteban Lopez Estrada and Martin Villegas Terrones, both of Leon, Guanajuato, Mexico. The other two men are Texas residents. Jorge Caraveo, of El Paso, Texas, was arrested in that city, and Oscar Cueva, of McAllen, Texas, was arrested there.

Each conspiracy count in the indictments carries a maximum penalty of five years incarceration and $250,000 in fines. Each smuggling and money laundering count carries a maximum penalty of 20 years incarceration and $500,000 in fines.

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In a settlement with environmentalists, US National Marine Fisheries Service has agreed to protect the “critical habitat” of elkhorn and staghorn coral in Florida. But they may end up doing more than that.

By protecting habitat, not just species, the federal government could be in a position to fight any threats to that habitat, including possibly, global warming, some environmentalists say. While no one expects the U.S. to stop, say, a coal-fired power plant in the Midwest to save Florida coral, the settlement does expand the leverage of the 1973 law that protects species from extinction.

“We think this victory on coral critical habitat actually moves the entire Endangered Species Act [ESA] onto a firm legal foundation for challenging global-warming pollution,” says Kieran Suckling, policy director of the Center for Biological Diversity, an environmental group based in Tucson, Ariz., that filed both coral suits.

Indeed, the coral-protection victory may be just the beginning of a push to use the ESA to fight global warming, he and other environmentalists suggest.

The pair of coral species are struggling to survive because Florida’s and the Caribbean’s waters have become warmer and more acidic. Many scientists attribute the change to global warming.

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Exotic creatures that live at deep-sea vents will not be immune to the effects of climate change, a UK scientist says.

It was thought that life at these fiercely hot volcanic fissures was so independent from the world above that the habitat would prove a safe haven. But new work finds that some of the animals are reliant on food sources from sea surface level, which could be affected by a change in climate.

Jon Copley, a marine biologist at the University of Southampton, who carried out the research, said: “These vents support lush islands of deep-sea life which is nourished by mineral-rich waters gushing out of the vents. “Thanks to this chemical energy source, these places seemed to be independent of the sunlit world above.” But Dr Copley has discovered this is not the case.He discovered that the creatures at this cold seep had a seasonal reproductive cycle. “The females spawn their eggs in autumn, brood them on the back legs during winter and they hatch out their young in early spring,” explained Dr Copley.

While seasonality in deep-sea creatures that live away from vents is connected to the availability of food sources, the vent’s shrimps have access to a plentiful food source all year round. “We believe the answer lies in the shrimps’ larvae,” Dr Copley said.

The team found that the larvae were leaving the vents and drifting to neighbouring vents where they completed their metamorphosis. “During that journey, they are feeding on material that is sinking down from the sunlit surface waters - and that food supply varies seasonally depending on where you are in the ocean,” explained Dr Copley. The adults were timing their reproduction to coincide with the point when there would be the most food for their offspring during their travels, he added.

Dr Copley said that this pattern has now been found in other shrimp species and mussels at volcanic vents. The biologist believes the finding could have wider implications. He said: “I used to think that what goes on in these vent environments was pretty much quarantined from what goes on in the sunlit world. “But this link suggests that changes to the life in sunlit waters can be communicated though to life in these remote corners of the ocean floor.

“If climate change were to alter life in surface waters, our work suggests that potentially such changes could be communicated to the ocean floor.” Other global catastrophes, such as an asteroid slamming into the Earth, would have a similar effect, he said.

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Drastic changes to land and water wrought by climate change are forcing cartographers to redraw their maps of the world.

Evidence of the effects of human activities on the Earth’s features–through climate change and construction efforts, such as irrigation projects—can clearly be seen in the new edition of The Times Comprehensive Atlas of the World, its editors say.

Many of the changes the map-makers have had to make involve the shrinking of lakes and seas and changes to coastlines:

• The Aral Sea in Central Asia has shrunk by 75 percent since 1967 (before/after).
• Lake Chad in Africa has shrunk by 95 percent since 1963 (before/after).
• The Dead Sea is 82 feet (25 meters) lower than it was 50 years ago.
• Sections of the Rio Grande and Colorado rivers in North America, the Yellow River in Asia and the Tigris River in the Middle East now dry out in the summer and at some times of the year the rivers don’t even reach the sea.
• The coastline of Bangladesh had to be redrawn because heavier monsoons and rising sea levels are causing more land to be lost to the ocean.
• Some Pacific Islands are also under threat from rising sea levels, including Kiribati, the Marshall Islands, Tokelau, Tuvalu and Vanuatu.

Future editions of the atlas, which typically is researched by a team of more than 50 cartographers, will take into account changes in Arctic sea ice cover and other changes to lake, river, ocean and forest boundaries, as they are affected by the changing climate.

The new edition of the atlas also notes that 40 percent of the world’s coral reefs have been destroyed or degraded in recent decades, and that more than 1 percent of tropical forest is cleared every year to make way for farmland.

On a more positive note, the atlas shows that 13 percent of the world’s land surface is now within designated protected areas worldwide.

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