First of let me say that I am sorry for the lack of post these last weeks. Internet problems. Will hopefully be back to normal soon. Now to the story

Hearing impairment caused by damage to hail cells in the inner ear is by far the most common cause of hearing loss, but research carried out on Zebrafish might be able to show us how these hair cells can be re-grown.

Scientists involved in the experiments say there could be therapeutic trials to prevent hearing loss using drugs within a decade, while finding a cure for hearing loss using hair-cell regeneration is probably at least 20 years away.

Hair cells in the inner ear can be damaged by a long row of factors, such as noise, drugs, disease and ordinary aging. Once a hair cell dies, mammals – including us humans – aren’t able to replace that hair cell with a new one. Until the mid-1980’s, researchers thought that this was true for all warm-blooded vertebrates, but we now know that birds are able to grow new hair cells and that this hair-cell regeneration can result in improved hearing.

Among the so called cold-blooded animals, aquatic creatures like the zebrafish are equipped with clusters of hair cells running along the outside of the body to help the animal sense vibrations in the water. Just like the birds, zebrafish are capable of regenerating these hair cells if there’re damaged and this has attracted the attention of U.S. researchers looking for a cure for hearing loss.

Why some animals can regenerate hair cells while other can’t, and why some animals – even within the same species – are more vulnerable to hair-cell death, remains a mystery.

“I literally walked around for years wondering about this variability,” says Ed Rubel, a professor of hearing sciences who leads part of a University of Washington research effort in Seattle.

The Seattle research teams are currently using zebrafish to gain a better understanding of hair cell generation in hope of figuring out how to protect human hair cells from becoming damaged and how to stimulate the cells to regenerate. The project is focused on understanding the molecules and genetics involved with hair cell regeneration, and how to mimic this process in animals that don’t spontaneously regenerate hair cells.

In collaboration with Dr. David Raible, another University of Washington scientist, Professor Rubel has already identified chemicals that seem to protect hair cells from damage. Those chemicals are now being tested on mice and rats to see if they will have an affect on warm blooded mammals and not just on zebrafish. The goal is to develop a medicine that can be administered to patients receiving drugs known to kill hair cells, e.g. chemotherapeutic agents.

Dr. Rubel’s and Dr. Raible’s teams also are studying the genetics of zebrafish to identify markers that confer hair-cell protection. The teams are also working on a separate group of studies regarding the genes and other molecules that make the regeneration of hair cells possible in zebrafish, birds and mice. In 2008, the teams jointly indentified several genetic mutations and drug-like compounds that seemed to protect hair cells from death, publishing their findings in the journal PLoS Genetics.

In addition to this, Dr. Rubel’s lab is investigating the role of the so called support cells; cells that surround the hair cells and are capable of both turning into hair cells and generate new hair cells. “If we understand the template of genes that are expressed by the cells we would want to divide, then we could tap into that template to mimic regeneration efforts in mammals”, Dr. Rubel explains.

How do hair cells work?

Hair cells are called hair cells since they look like cells with little hairs growing out of them when you look at them through a microscope. Hair cells are found in our inner ears and damage to these cells is a major cause of irreversible hearing loss. The filament hairs, also known as cilia, bend as sound waves enter the ear, prompting the hair cell to send an electrical signal to the auditory nerve from which it continues to the brain.

A 100 metre by 100 metre* anchor-free zone will be established in Studland Bay in Dorset bay to protect the largest seahorse breeding colony in the United Kingdom. To prevent boaters from accidently anchoring within the zone, it will be marked out by six large buoys fitted with flags on top.

“There might be the odd individual who out of spite or grievance will chose to go on there but it will be well marked so if anyone does it will be intentional”, says Natural England maritime advisor Richard Caldow.

The area will be patrolled by wardens and a map of boating activity will be constructed based on their observations during the busy summer season. Marine experts will then compare data from the anchor-free zone to a control zone where boats can anchor.

“I’m not interested in the names of boats”, Caldow says. “I want to know how many there are and where they are going, particularly the level of boating in the voluntary no anchor zone which will hopefully be none.”

* 109 x 109 yards

If everything goes according to plan, the world’s largest ocean observatory will be ready for use by late September, except for the instruments at one node which won’t be installed until next year.

“Scientists and staff at NEPTUNE Canada are delighted to begin the final phase of installation following a decade of planning,” says Dr. Chris Barnes, director of NEPTUNE Canada.

NEPTUNE Canada, the world’s most advanced cabled ocean observatory, consists of five 13-tonne nodes and more than 400 instruments and sensors that will be placed on the seafloor off the coast of British Columbia with the aid of three ships, one Remotely Operated Vehicle (ROV), and a team of scientists and marine engineers. The observatory will be attached to a loop of powered fibre-optic cable which was put in place in 2007.

NEPTUNE Canada will use the Internet to transmit information to land-based scientists across the world, thus making it possible for researchers to experiment and investigate the deep sea without having to get their feet wet (or die from the immense pressure). NEPTUNE Canada will also carry out long-term monitoring of ocean processes and events.

“This is truly transformative science,” says Dr. David Turpin, president of the University of Victoria. “At a time when our understanding of the oceans is clearly becoming more essential than ever, NEPTUNE Canada will play a leadership role in advancing our knowledge of the oceans in ways not previously possible. We are launching a new era of ocean exploration.”

NEPTUNE Canada has been designed to withstand the intense pressure and cold of the deep sea as well as trawlers and corrosive saltwater.

“Working with industry partners, we’ve developed a host of novel science experiments, advanced engineering and sensor technologies and innovative data management systems”, says Dr. Barnes. “This is a very exciting time for ocean science.”

A lot of the technology fitted to the observatory is cutting-edge solutions that are now being deployed for the very first time.

Much of the infrastructure for NEPTUNE Canada is being designed, manufactured and installed by Alcatel-Lucent and its main subcontractors. Other main partners are the University of Victoria, the research ship Atlantis operated by the Woods Hole Oceanographic Institution and the research ship Thompson operated by the University of Washington. The project is funded chiefly by the Government of Canada, the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada, CANARIE, and the Government of British Columbia through the BC Knowledge Development Fund.

After being boosted by the recent heat wave, massive amounts of zooplankton is now attracting record numbers of basking sharks into British and Irish waters.

Last year, 26 basking sharks were reported from the most southerly headland of Cornwall during a 10 week long period. This year, 900 sightings have been recorded since the beginning of June.

“Last year we had a really poor year because of the weather. But even though temperatures have obviously picked up, we never expected to see the sharks in such large numbers,” saysTom Hardy of Cornwall Wildlife Trust, coordinator of the south-west basking shark project.

Record breaking numbers of basking sharks are being reported from the other side of Irish Sea as well. In June alone, the Irish Whale and Dolphin Group reports having seen no less than 248 basking sharks.

“In a three-day period we tagged more than 100 sharks in just one bay in north
Donegal,” says Simon Berrow of the Irish Whale and Dolphin Group. “You only ever see five or six of these creatures on the surface, which doesn’t reflect what’s going on under the water.”

From the Isle of Man, 400 sightings have been reported since early May.

‘”We saw a lot more in May than is usual and after a couple of quiet weeks sightings are picking up again,” said Fiona Gell, marine wildlife officer for the Isle of Man government.

Very little is known about the basking sharks, but the Irish Whale and Dolphin Group is currently carrying out a pioneering tagging project in hope of furthering our understanding of these basking giants. Simultaneously, the 47 wildlife trusts found across the UK, the Isle of Man and Alderney are working to identify basking shark hotspots.

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.

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.

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