Fish and aquatic news

The Nature Conservancy and its partners’ staghorn and elkhorn coral recovery project, including Lirman’s nursery in Biscayne National Park, will receive $350,000 to help save U.S. reefs.

The news was announced yesterday by the National Oceanic and Atmospheric Administration (NOAA), who also said that the money, which will come from the American Recovery and Reinvestment Act (ARRA), will be used to further develop large-scale, in-water coral nurseries and restore coral reefs along the southern coast of Florida and around the U.S. Virgin Islands.

The Nature Conservancy will serve as coordinator of the overall project; a project which will include the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, as well as other academic, government and private entities.

The project goal is to grow approximately 12,000 corals in Florida and use them to enhance coral populations in 34 different areas.

A Japanese team of scientists are now announcing that they are close to completing genome sequencing of the Bluefin tuna. Once they have reached this goal, their next project will be to use their knowledge to create a tuna breeding program for a new type of tuna specially designed for aquacultures.

The wild tuna populations have become severely depleted due to overfishing and the WWF has warned that the Atlantic Bluefin tuna will be eradicated within three years unless radical measures are taken to safeguard remaining specimens.

“We have already completed two computer sequencing runs and have around 60 per cent of the tuna genome,” says Dr. Kazumasa Ikuta, director of research at the Yokohama-based Fisheries Research Agency. “We expect to have the entire sequence in the next couple of months. We plan to use the sequence to establish a breeding programme for bluefin tuna as most aquaculture farmers presently use wild juveniles. We want to establish a complete aquaculture system that will produce fish that have good strength, are resistant to disease, grow quickly and taste delicious.”

The genome sequencing is the result of the collaborative efforts of scientists from Japan’s Fisheries Research Agency, Kyushu University, and The University of Tokyo.

The Australian government will spend 200 million AUD to improve the water quality around the Great Barrier Reef in what Agriculture Minister Tony Burke calls a “once-in-a-lifetime chance to resuscitate the reef”.

The first “downpayment”, consisting of 50 million AUD, was committed on Thursday. The money will be divided between agriculture industry groups, natural resource management bodies, and the WWF (World Wide Fund). The recipients will work to increase the water quality by promoting better farming practices on land. The short-term goal is to reduce nutrient and chemical discharge into the reef environment by 25 percent from next year.

“Farmers hold one of the keys to the reef’s long-term health - they understand the land and how to manage it in a smart, productive way,” Burke said in a statement.

Specimens of the invasive Blue catfish (Ictalurus furcatus) have now grown large enough to reach the top of the food chain in James River, Virginia. A catfish weighing 102 lbs (46 kg) was caught from the river not long ago; the largest caught freshwater fish ever to be reported from Virginian waters.

30 years ago, Blue catfish was deliberately introduced to this U.S. river as a game fish. During recent years, the catfish population has grown explosively while many other fish species have decreased. An eight year old Blue catfish normally weigh a mere 4 lbs (1.8 kg), but as soon as it gets large enough to start catching other fish and devouring fully grown crabs, it begins putting on weight at a rapid pace and can gain as much as 10 lbs (4.5 kg) a year.

Blue Catfish - Ictalurus furcatus. Copyright www.jjphoto.dk

According to Bob Greenlee, a biologist with the state Department of Game and Inland Fisheries, scientists doing sampling used to get around 1,500 catfish in an hour in this river in the 1990s. Today, this number has increased to 6,000. “We have an invasive species that is taking over the ecosystem,” says Rob Latour, a marine biologist with the Virginia Institute of Marine Science at the College of William and Mary.

The world’s first public aquarium specialising in clownfish has now opened its door for visitors. The aquarium, which is located in Taitung County in Taiwan, will eventually house 1500 clown fish from 18 different species.

The aim of the clownfish aquarium is to educate the public about clownfish life-cycles and captive breeding techniques, and specimens will be sent to the aquarium by breeders such as the Eastern Marine Biology Research Center in Taitung.

“By meeting market needs we are helping to ease the crisis of clownfish species being endangered”, says researcher and museum planner Ho Yuan-hsing. “Due to the increasing number of artificially-bred clown fish, the fishing of clownfish is no longer seen in Taiwan’s coastal areas because it is unnecessary.”

AC comment:

The movie “Finding Nemo” made a lot of people interested in getting their own “Nemo”, but few were willing to learn how to properly maintain a saltwater aquarium. Before you decide to get a clownfish, please keep in mind that these are marine fishes. Simply adding some salt to your freshwater aquarium will not make is a suitable home for marine fish; not even for the sturdy clownfish. Even though the worst Nemo-craze seems to have cooled off now, a lot of “Nemos” still face an early death in the hands of uninformed fish keepers; deaths that could have been easily prevented.

Norwegian fisheries regulators have banned all fishing of the critically endangered European eel starting in 2010 and cut 2009 catch quotas by 80 percent. The Norwegian Ministry of Fisheries also has announced that all recreational fishing of European eels shall stop on July 1st.

The European eel (Anguilla anguilla) is listed as critically endangered in Norway and on the IUCN Red List of Threatened Species. As early as 1999, the International Council for the Exploration of the Seas (ICES) warned fishery authorities about how the European eel stock was outside safe biological limits and that the fishery was unsustainable.

”The Minister of Fisheries is making an important, and the only right choice, and is showing international leadership in fisheries management,” said WWF-Norway CEO Rasmus Hansson in a response to the new regulation. “Norway’s Fisheries Minister, Helga Pedersen, has used every occasion to point out that Norway is the best in the world on fisheries management, and by making bold moves like this they have probably earned the title.”

WWF now hopes that the Norwegian decision will influence the European Union and its member states to do their part in protecting the European eel. As of today, eel fishing is allowed within the EU despite the grave condition of the European stock.

This Sunday, a mile-long super pod consisting of over 1,500 dolphins was encountered by eight lucky Sea Trust volunteers off the coast of Pembrokeshire, UK.

The volunteers were doing a small boat survey when suddenly confronted with what they first thought was a blizzard in the distance.

“As we approached, we realised that the ‘blizzard’ was thousands of gannets* spreads out over a mile or more,” said Sea Trust founder Cliff Benson.

The enormous pod, consisting of adult dolphins and their offspring, formed a veritable wall as they hastily rushed thought the water, probably in pursue of fish.

“They just kept on coming pod after pod passing by the boat some came and looked at us but most just kept on going”, said Benson. “The gannets were like an artillery bombardment
continually diving in with an explosion of spray, just ahead of the line of dolphins.”

According to Benson, the pod was most likely the result of many smaller pods that had joined together to follow a huge “bait ball” of fish.

In August 2005, a similar super-pod was filmed off Strumble Head, and last weeks spotting of a second one has caused Benson to suggest that super-pods might be a regular phenomenon in these waters.

* Gannets are a type of large black-and-white birds.

Twelve thefts of exotic fish and pond equipment have been reported over a three-week period across Hull, East Yorks.

Humberside Police Community Support Officer Sam Gregory said all the evidence suggests the culprits are using the Internet to seek out their targets.

A picture of a kohaku Koi carp in a pond Copyright www.jjphoto.dk

“Google shows what is in your garden and you can see people’s ponds“, Gregory explained.

“One of the properties targeted has an eight foot fence and is set back from the road. The pond is in the corner and can’t be seen. Unless you were standing right next to the wall, you wouldn’t be able to hear the running water.”

In association with one of the thefts, where four small koi carps and some expensive lilies were taken, a neighbour report seeing two young men with a bike with a box on it and a big black net.

“Criminals could use maps, phones and getaway cars but no one would argue that these technologies are responsible for the crime itself, that responsibility lies with the perpetrator”, a Google spokesperson said, adding that Google is just one of several providers of detailed satellite images.

“For the Florida Keys’ reefs, overall, the live coral cover has diminished by 50 to 80 percent in the past 10 years,” says Margaret Miller, a coral reef researcher at the National marine Fisheries Service. According to Miller, the destruction is the result of several contributing factors, such as pollution, climate change, over-fishing, and coastal developments.

“Corals are very susceptible to warming temperatures, because their lethal temperature [temperature at which they die] and their happy, normal temperature are very close, only separated by a couple of degrees,” Miller explains.

The reef building corals are not the only creatures in trouble in Florida; the situation looks dire for many reef associated species as well.

University of Miami marine professor Jerry Ault has studied marine life in the region for more than a decade.
“The research has discovered that about 70 percent of all the snapper and grouper in the Florida keys reef system are at population levels below those considered to be sustainable,” he said. “Everybody loves Florida because of the marine environment. Folks come here to fish and to dive and to take advantage of it, but we are loving it to death.”

One of the most controversial environmental issues of the past decade now seems to have been solved thanks to the consolidated efforts of one U.S. and one U.K. researcher.

In the late 1980s and early 1990s, researchers started getting reports of numerous deformed wild frogs and toads. Many of them missed a limb partly or completely, while others – even more strikingly – had extra legs or extra arms.

The reason behind the deformities became a hot-potato, with some people suspecting chemical pollution or increased UV-B radiation (brought on by the thinning of the ozone layers), while others leaned towards predators or parasites.

“There was a veritable media firestorm, with millions of dollars of grant money at stake,” says Stanley Sessions, an amphibian specialist and professor of biology at Hartwick College, in Oneonta, New York.
Eventually, professor Sessions and other researchers managed to show that many amphibians with extra limbs were actually infected by small parasitic flatworms called Riberoria trematodes. These nematodes burrow into the hindquarters of tadpoles and rearrange the limb bud cells. This interferes with limb development, and in some cases the result is an extra arm or leg.

While these findings explained the conspicuous presences of additional limbs, it wasn’t enough to solve the mystery of the leg- and armless amphibians.

“Frogs with extra limbs may have been the most dramatic-looking deformities, but they are by far the least common deformities found,” Sessions explains. “The most commonly found deformities are frogs or toads found with missing or truncated limbs, and although parasites occasionally cause limblessness in a frog, these deformities are almost never associated with the trematode species known to cause extra limbs.”

To investigate the conundrum, Sessions teamed up with UK researcher Brandon Ballengee of the University of Plymouth. As a part of a larger research project, the two scientists placed tadpoles in aquariums and added various predators to see if any of them could be responsible for this type of injuries.

As it turned out, three different species of dragonfly nymph happily attacked and nicked of the hind legs of the tadpoles; feasting on the tasty legs without actually killing the tadpoles.

“Once they grab the tadpole, they use their front legs to turn it around, searching for the tender bits, in this case the hind limb buds, which they then snip off with their mandibles,” says Sessions. “Often the tadpole is released […],” says Sessions. “If it survives it metamorphoses into a toad with missing or deformed hind limbs, depending on the developmental stage of the tadpole.”

Eating just a leg instead of trying to kill the entire tadpole is beneficial for the dragonfly, since tadpoles develop poison glands in their skin much earlier than those in their hind legs.

Through surgical experiments, Sessions and Ballengee confirmed that losing a limb at a certain stage of a tadpole’s life can lead to missing or deformed limbs in the adult animal. Really young tadpoles are capable of growing a new limb, but they loose this ability with age.

Sessions stresses that the results of his study doesn’t completely rule out chemicals as the cause of some missing limbs, but says that this type of “selective predation” by dragonfly nymphs is now by far the leading explanation.

“Are parasites sufficient to cause extra limbs?,” he asks. “Yes. Is selective predation by dragonfly nymphs sufficient to cause loss or reduction of limbs. Yes. Are chemical pollutants necessary to understand either of these phenomena? No.”

You can find Sessions and Ballengee’s study in the Journal of Experimental Zoology Part B: Molecular and Developmental Evolution.

Sea Lamprey spawning sites have been discovered in the River Wear at Chester-le-Street, County Durham, by local anglers. After being alerted by the fishermen, the Environment Agency found no less than 12 spawning sites, known as redds, measuring up to a metre across.

“We were thrilled to discover lampreys back in the River Wear as these rare blood-suckers show us that the water quality in the river is very high“, says Environment Agency fisheries officer Paul Frear. “Lampreys are extremely selective with their spawning sites and will only nest where the water quality is optimal. Today, only three species of this blood-sucking creature remain in Britain and their habitats are protected by an EC directive.”

The lamprey feeds by attaching itself to another animal with its suction-cup like mouth and, once in place, gradually rasps away tissue from its host. The largest specimens are roughly 100 cm long, but most lampreys are smaller than this.

If you see a lamprey or a lamprey redd (nest) in the UK, please report the sighting directly to Paul Frear by e-mailing him at paul.frear@environment-agency.gov.uk.

As reported earlier, invasive sea lampreys have caused serious problems in North America where they lack natural enemies.

Picture is from North America where the lamprey have caused serious problems.

You have probably noticed it if you’ve ever tried to catch a fish using your bare hands or a small net: the uncanny ability of these creatures to escape, sometimes even before you make a move. Most fish species are incredibly fast and seem to be virtual mind-readers when it comes to predicting when and where you will make your next attempt.

The reason behind this remarkable talent is a special circuit present in the brains of many species of fish. Fish ears constantly sense the sound pressure on each side of the body and if the ear on one side detects a disturbance, the muscles of the fish will automatically bend the body into a c-shape facing the opposite direction. This involuntary reaction makes it possible for the fish to start swimming way from harms way as quickly as possible. Scientists call it C-start and it is highly advantageous when escaping from predators. That is, until you venture upon the Tentacled snake (Erpeton tentaculatum) of South-East Asia.

While studying the Tentacled snake, Kenneth Catania, associate professor of biological sciences at Vanderbilt University, realized that this snake has found a way of exploiting the C-start reflex to its advantage.

Using video recordings of snake (see below) and prey Catania was able to slow down the chain of events enough to make them noticeable for a human eye, and what he saw amazed him. Instead of fleeing from the snake, fish would swim right into the mouth of the predator nearly four times out of five. How could this be?

When hunting, the Tentacled snake forms its body into a peculiar J-shape with its head at the bottom of the “J”. It then remains absolutely still until suitable prey ventures close enough to the “hook”-area of the J. When it finally strikes, it rarely misses since the fish seem to be magically drawn to the jaws of their attacker. In 120 attacks carried out by four different snakes, Catania observed no less than 78 percent of the fish turning toward the snake’s head instead of swimming away from it.

Catania also noticed something else: before the snakes moved their head to strike, they always flexed a point midway down the body. A hydrophone placed in the aquarium unveiled that by flexing its body, the snake produces sound waves intense enough to trigger the fish’s C-start reflex, and since the sound comes from a spot opposite the head of the hungry snake, the C-start reflex forces the fish to turn and swim directly towards the snake’s mouth.

“Once the C-start begins, the fish can’t turn back,” Catania explained. “The snake has found a way to use the fish’s escape reflex to its advantage. I haven’t been able to find reports of any other predators that exhibit a similar ability to influence and predict the future behavior of their prey,”

The C-start behaviour is actually so predictable that the snake doesn’t even bother to aim for the initial position of its prey and then adjust its direction as most predators would. Instead, it goes directly for the spot where it knows the fish will be heading.

“The best evidence for this is the cases when the snake misses,” says Catania. “Not all the targeted fish react with a C-start and the snake almost always misses those that don’t react reflexively.”

Kenneth Catania studies the brains and behaviour of species with extreme specializations. His new snake study is published this week in the online early edition of the journal Proceedings of the National Academy of Sciences.

Most IWC* member countries accidently kill whales, e.g. by unintentionally ramming into them with motorized vessels or by using fishing methods that may entangle and suffocate these air-breathing mammals as accidental by-catch. While this type of accidental deaths is reported from most member nations, Japan and South Korea have an inordinate amount of accidental by-catchs, says Professor Scott Baker, associate director of the Marine Mammal Institute at Oregon State University.

By analysing the DNA of whale-meat products sold in Japanese markets, Baker, a cetacean expert, and Dr Vimoksalehi Lukoscheck of the University of California-Irvine, found that meat from as many as 150 whales came from the coastal population. Japan’s scientific whaling program only targets whales from open ocean populations, but whales accidently killed outside the program are allowed to be sold.

Humpback Whale

Japan and South Korea are the only countries that allow the commercial sale of products derived from whales killed as accidental by-catch and the sheer number of whales represented by whale-meat products on the market suggests that there might be something fishy about these allegedly accidental kills.

They DNA study showed that nearly 46 percent of examined Minke whale products came from a coastal whale population, which has distinct genetic characteristics, and is protected by international agreements. In addition to minke whales, Baker and Lukoscheck also found DNA from Humpback whales, Bryde’s whales, Fin whales, and Western gray whales.

“The sale of bycatch alone supports a lucrative trade in whale meat at markets in some Korean coastal cities, where the wholesale price of an adult minke whale can reach as high as $100,000,” Baker said. “Given these financial incentives, you have to wonder how many of these whales are, in fact, killed intentionally.”

In January 2008, Korean police launched an investigation into organized illegal whaling in the port town of Ulsan, reportedly seizing 50 tons of minke whale meat.

Japan has asked the IWC, who is holding its annual meeting this week, to allow a small coastal whaling program in Japanese waters. This request is something that professor Baker says should be scrutinized carefully because of the uncertainty of the actual catch and the need to determine appropriate population counts to sustain the distinct stocks.

Baker and Lukoscheck have presented their findings to the IWC commission and the study will also be published in a forthcoming issue of the journal Animal Conservation.

* International Whaling Commission

Norway, one of the two countries that openly defy the IWC ban on commercial whaling, has suspended this year’s whale hunt mid-season after catching less than half the quota of 885 whales. The suspension coincides with this week’s annual IWC meeting in Portugal, but is not linked to the meeting or any adjacent negotiations. Instead, a lack of demand in the Norwegian distribution chain is cited as the reason behind the surprising deferment.

“The number of whales killed so far is enough to meet the known demand,” said Willy Godtliebsen, head of sales at the Norwegian Fishermen’s Sales Organisation (NFSO). “They may resume the hunt later if new buyers turn up.”

According to NFSO marketing director Lise Mangseth, the suspension is an effect of the current financial crisis. The financial situation has dissuaded processing plants from freezing and stocking the meat the way they normally do, in order to save money.

“More generally, [the suspension is due to] organisational problems rather than a problem of demand,” Mangseth said. “The whalers are such small actors and the volumes from the hunt are so limited that the distribution chains don’t really want to invest in their product and there are no marketing campaigns as there are for other food products“.

She also claimed that it isn’t unusual for whalers to take a break during the season.

Greenpeace are interpreting the suspension as a sign of waning consumer demands for whale meat.

“If they don’t start the hunt again later this season, 2009 will be the ‘worst’ year for whaling since Norway resumed commercial whaling”, Greenpeace spokesman Jo Kuper said.

Norway resumed whaling in 1993, despite international protests. When Norwegian whalers were asked to suspend their hunt on Tuesday this week, 350 Minke whales had been harpooned since the start of the whaling season in April. Normally, the hunt would continue until October.

Up to 50 lungfish, some of them up to on metre long, was killed when tonnes of water was released from an Australian dam this week.

The water was released from the North Pine Dam in southeast Queensland between Monday morning and Tuesday night as heavy rains were threatening to overfill the dam.

According to SEQWater, who manages the North Pine Dam, up to 100 native fish went with the release, including roughly a dozen lungfish. SEQWater spokesman Mike Foster said staff were on the scene at every dam release to check for “fish kills” and that they had rescued a handful of lungfish from pools. He also stated that staff would return on Thursday [today] to see if more could be done.

In May, when the North Pine Dam opened its gates for the first time in many years, up to 150 lungfish were rescued.

Roger Currie, spokesman for the Wide Bay Burnett Conservation Council, said conservationists on the scene during the most recent water release had found up to 50 lungfish that had been killed or mutilated as a result of the release.

“Some were found caught in trees yesterday and last night,” Currie said. “They’ve just been pummelled by the sheer force of it.”

The Wide Bay Burnett Conservation Council is pushing for a study to find out how large the North Pine Dam lungfish population is, and the council is also calling for measures to protect fish during water releases.

Lungfish of the species Neoceratodus forsteri.
Copyright www.jjphoto.dk

What’s so special about the Australian lungfish?
The Queensland lungfish, Neoceratodus forsteri, is the only now living member of the family Ceratodontidae and order Ceratodontiformes. Also known as Australian lungfish or Barramunda, Neoceratodus forsteri is native only to the Mary and Burnett river systems in south-eastern Queensland. It has however been introduced to several other Australian rivers south of this area during the past century.

Fossil records of the lungfish group date back 380 million years to a period when the higher vertebrate classes were at the starting point of their development. Prehistoric fossils unearthed in New South Wales are almost identical to the now living Qeensland lungfish, indicating that this species hardly has evolved at all during the last 100 million years. Lungfishes flourished during the Devonian period (c. 413-365 million years ago) but only six species of freshwater lungfish remain today; one in Australia, one in South America, and four in Africa.

The Queensland lungfish can survive for several days out of water, but only if kept moist. It can breathe oxygen directly from the air using its lung-like swim bladder. This species is remarkably long-lived compared to most other fish species and will usually attain an age of at least 20-25 years if it manages to survive into adulthood. Granddad, a Queensland lungfish living at the Shedd Aquarium in Chicago, is at least 80 years old. He has been housed at the aquarium since 1933 and seen many generations of zoo keepers come and go. The largest