Scubaism

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 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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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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An almaco jack seems to have travelled over 4,000 miles and ended up in Cornwall. It was snared by fisherman Phil Trebilcock off Crantock and taken to the Blue Reef Aquarium in Newquay. David Waines from the Blue Reef Aquarium thinks it hitched a ride on a ship or simply got lost.

“No one is entirely sure why a fish that is normally native to tropical waters should have been discovered just offshore. There is an outside chance that it could have been carried over in the ballast tanks of a large vessel.

“But I suppose the most likely reason is that it simply got lost and somehow ended up thousands of miles off course.

“Sea temperatures around Cornwall peak at around this time of year at 16C-17C so it is possible for warmer water species to survive.

“However, in winter they drop back by 10C-12C and therefore exotic fish only have a small window of opportunity to survive.”

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One of Britain’s rarest fish is returning in large numbers, the Environment Agency said today. Scientists have witnessed a massive resurgence in the sea lamprey population in the River Tamar and have recorded five times more fish than the seasonal average. The Environment Agency (EA) picked up the increase in lamprey numbers while recording migrating salmon at Gunnislake, Cornwall, as they swim upstream.

The EA welcomed the resurgence as it indicates a healthy river environment and said the metre-long sea lamprey is a primitive marine species that comes into rivers to spawn.

The eel-like fish has a jawless mouth and is boneless with a skeleton made of flexible cartilage. Spokesman for the EA, Paul Elsmere, said: “The sea lamprey is something of an evolutionary throwback, but it is an important indicator species.

“This year more than 500 have passed through our fish counter at Gunnislake which is excellent news as it shows water quality in the Tamar is high.” The EA said the sea lamprey are thought to be more sensitive to pollution than salmon so their presence on any river system is to be encouraged.

For centuries the fish was considered a delicacy in Europe and King Henry I is said to have died from a “surfeit of lamprey”. In Finland, hot-grilled lamprey it still a favourite dish although there is no commercial fishery for sea lamprey in the UK and little is known of its behaviour at sea.

It feeds by attaching itself to other fish using its sucker mouth. Once attached it uses its sharp tongue to rasp a hole in the side of the fish before feeding on its host’s blood. The lamprey later detaches itself and swims off in search of its next meal. The EA said it rarely kills other fish.

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Dolphins, seals and porpoises could soon become a far more common sight along the Thames, scientists said today. More than 100 of the sea mammals have been spotted in the river over the last year. Researchers say numbers could greatly increase in coming years as the creatures begin to feed in the river more often because of an increased number of fish.

The figures come from the Zoological Society of London’s marine mammal sightings survey. It found that bottlenose dolphins, common and grey seals and harbour porpoises were a common sight between Richmond and the estuary at Southend.

Dr Renata Kowalik, from the society, said: “We have anecdotal evidence that numbers are increasing, although this is only our second year of data so it is hard to predict a trend. We are seeing a lot of seals in Docklands, and we believe the increased number of fish mean they are feeding in the river now.”

Dolphins have moved further up the Thames, with one sighting between Westminster Bridge and Tower Bridge. However, the survey also indicates that sea mammals which make their way as far as Tower Bridge may find themselves in a precarious situation.

Several dead harbour porpoises have been reported shortly after live sightings, and have suffered injuries consistent with boat and propeller collisions. Dr Kowalik said: “Some areas of the river can be very dangerous for these animals, so we need to monitor exactly where they are.

“We are going to be working with several studies in other parts of the UK to see if the increases we see are mirrored elsewhere. We would urge members of the public to take part - we need all the sightings we can get.”

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Passengers aboard the whale watching ship Moby Dick, sailing off the coast of Reykjanes peninsula, southwest Iceland, were caught by surprise yesterday when they spotted a strange creature—not a whale—swimming in the ocean alongside the boat.

“We saw that there was something other than a whale swimming near the surface. […] The creature was surrounded by dolphins and it looked like they were trying to help it,” Helga Ingimundardóttir, who operates Moby Dick, told Morgunbladid. “It swam near the surface for quite some time so we got a good look at it before it disappeared.”

The strange creature turned out to be 1.2 to 1.5-meters-long Loggerhead Sea Turtle, which can weigh up to 360 kilos. Such turtles are common in the Mediterranean and by the North American coastline, but are usually not found in Icelandic waters.

Ingimundardóttir notified the Icelandic Marine Research Institute about the discovery. Droplaug Ólafsdóttir, a biologist at the institute, said the turtle’s visit is very unusual.

Ólafsdóttir explained that the ocean temperature is warmest around Iceland at this time of year and espoused that could be a possible reason for the turtle getting lost, adding that she did not expect more turtles to follow.

A giant sea turtle has been spotted in Icelandic waters on one other occasion, in Steingrímsfjördur fjord in the eastern Westfjords in 1963. It was 2.03 meters long and 375 kilos. The turtle is on display in the Icelandic Institute of Natural History.

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A tropical algae thriving on fertilizers from hotel golf courses and badly treated sewage is killing one of Costa Rica’s most important coastal reefs, scientists say.

The green, feather-like algae is spreading along the reefs of Culebra Bay in Costa Rica’s northwestern Gulf of Papagayo, a popular scuba diving spot and home to a rare species of coral. The algae blocks the sunlight and suffocates the reefs.

A tourism and construction boom along the palm tree-lined beaches is creating nitrogen- and phosphate-rich waste that feeds the algae, known as Caulerpa sertularioides, and Costa Rica is only just becoming aware of the problem. “It’s an ecological disaster,” said Cindy Fernandez, a marine biologist with the nonprofit MarViva Association, who alerted the Costa Rican government to the threat, which is now being taken on by the state-run University of Costa Rica.

Scientists say about 80 percent of the reef area, which stretches for about a mile and a half (2.4 km) along the coast line, is covered in the algae. The aggressive algae spreads when even the smallest sliver comes loose, from the likes of strong currents or dive boats dropping anchor, to root itself in another part of the reef. Even the sweep of a diver’s hand or the kick of a diver’s fin can send a fragment swirling away to start another patch.

That means experts cannot pull it up like weeds. “If you pull it up it will reproduce faster,” said Jenny Asch, coordinator of the government’s marine conservation program, who is leading efforts to find a way to eradicate the algae. If left unchecked, the algae could also severely damage the ecosystem of the bay, allowing non-native species of fish to come in and displace the native species.

The highly invasive Mediterranean strain of the algae, Caulerpa taxifolia, was discovered in Southern California in June 2000, where scientists have used solid chlorine blocks to eradicate the pest. Costa Rican scientists do not yet know if similar eradication techniques will work on Caulerpa sertularioides.

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A huge swathe of China’s booming Pearl River Delta will be “engulfed” by rising sea water by the middle of the century because of global warming, state media said on Thursday, quoting weather officials.

Some 1,153 square km of coastal land would be flooded by 2050, with the bustling cities of Guangzhou, capital of Guangdong province, Zhuhai and Foshan the worst affected, the China Daily said, quoting the provincial water authority. Hotter average global temperatures fuelled by greenhouse gases meant the sea level along the coast of Guangdong was forecast to rise by at least 30 cm by 2050.

“Climate change will negatively affect the economic development of Guangdong, which is currently one of the biggest consumers of energy and producers of greenhouse gases,” Du Raodong, an expert at the Guangdong weather centre, was quoted as saying. The rising sea level would lead to a salt tide, posing a huge threat to drinking water supply. “Moreover, red tides (caused by high concentrations of algae) will occur along coastal areas, affecting agricultural production,” said Du.

Yu Yong, director of the Guangdong bureau, warned that global warming would bring about more drought and floods, causing huge economic losses. “More energy-saving industrial facilities should be introduced in a bid to reduce greenhouse gas emissions,” Du said.

Torrential rain has inundated large swathes of China’s east, south and southwest since June while a prolonged heat wave and drought have afflicted several eastern provinces. More than 1,000 people have been killed in floods, mudslides and collapsed houses so far this year. “The climate has been abnormal,” Vice Minister of Water Resources E Jingping told a news conference this week.

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Foam swallowed an entire beach and half the nearby buildings, including the local lifeguards’ centre, in a freak display of nature at Yamba in New South Wales. It stretched for 30 miles out into the Pacific in a phenomenon not seen at the beach for more than three decades.

Scientists explain that the foam is created by impurities in the ocean, such as salts, chemicals, dead plants, decomposed fish and excretions from seaweed. All are churned up together by powerful currents which cause the water to form bubbles. These bubbles stick to each other as they are carried below the surface by the current towards the shore. As a wave starts to form on the surface, the motion of the water causes the bubbles to swirl upwards and, massed together, they become foam.

The foam “surfs” towards shore until the wave “crashes”, tossing the foam into the air. “It’s the same effect you get when you whip up a milk shake in a blender,” explains a marine expert. “The more powerful the swirl, the more foam you create on the surface and the lighter it becomes.”

In this case, storms off the New South Wales Coast and further north off Queensland had created a huge disturbance in the ocean, hitting a stretch of water where there was a particularly high amount of the substances which form into bubbles.

As for 12-year-old beachgoer Tom Woods, who has been surfing since he was two, riding a wave was out of the question. “Me and my mates just spent the afternoon leaping about in that stuff,” he said. “It was quite cool to touch and it was really weird. It was like clouds of air - you could hardly feel it.”

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