The huge oarfish has been filmed by scientists operating a tiny submarine by remote. This may be the first time this fish is filmed, or even seen, in its natural environment. The species might have been caught on camera at a depth of 765 meters during a research mission off the coast of western African in 2007, but marine experts haven’t been able to positively identify the creature in that video.

Oarfish are large, elongated fishes belonging to the family Regalecidae. The family contains four species of which the largest one is the famous King of Herrings (Regalecus glesne), listed in the Guinness Book of World Records as the longest bony fish alive today. The largest known King of Herring was 17 metres (56 ft) in lenght.

Normally, this deep-dweller is only encountered when dead ones are washed ashore or when dying specimens are brought up to the surface by fishermen.

The research crew was therefore happily surprised when an oarfish suddenly showed up in front of their camera.

“We saw this bright vertical shiny thing, I said ‘are they lowering more riser?’ as it looked like they were lowering a huge pipe,” said Mark Benfield from Louisiana State University, Baton Rouge, USA, one of the scientists working at the Serpent Project in the Gulf of Mexico.”We zoomed in a little bit and we said ‘that’s not a riser that’s a fish!’ As we approached it retreated downwards swimming tail first in a vertical orientation as the ROV followed. What was interesting about the fish was its swimming behaviour. It moved by undulating its dorsal fin in waves that propelled it backwards at quite a good speed.”

Early estimates measure the fish at between 5m and 10m in length, which roughly equals 16-33 feet.

The Serpent Project is a collaboration between marine researchers and energy companies such as Petrobras, Chevron and Shell and involves the use of remotely operated vehicles (ROV’s) to explore depths to which it would be extremely dangerous to send a human. Responsible for the project is the National Oceanography Centre in Southampton, USA.

The King of Herrings is believed to be the creature behind the ancient myths about gigantic sea serpents. It has a prominent dorsal fin, almost like the continous spikes of a fairytale dragon.

In south-east Asia and northern Australia, Archer fish can be seen spitting jets of water up to three meters to knock out insects and spiders and make them fall into the water. Archer fish does for instnace help control the populations of mosquitoes and flies.

In captivity, insects in the air can be scarce – especially during the chilly Bristol winter. That is why a shoal of archer fish living at Bristol’s Blue Reef Aquarium have been given a mobile dotted with plastic flies for target practise.

The archers living in the aquarium are roughly 1.5 years of age and staff said that their natural hunting instinct may have become rusty. To combat this, the staff is now smearing the fake flies with bloddworm so that when a fish manages to hit a fly, tasty bloodworm falls down into the water.

“In the summer if we have some insects flying around I’ll be surprised if they don’t go for them,” said senior aquarist Lindsay Holloway.

Residents of the Daluo village in China’s Guangxi province have caught several weird looking yellow fishes in a cave lake located 1,000 meters (3,280 feet) below ground.

Experts working at the Bama County and Guangxi provincial aquatics institutes have been unable to indentify the fish, which sports a flat mouth shaped almost like the bill of a duck and eye-catching red lips. The mysterious creature is also adorned with a long, slim “moustache”.

According to Li Zuneng, head of the village, members of his community have heard stories about this outlandish fish told by the oldest villagers, but many had assumed that it was some type of fairytale creature. Up until now, no one from the younger generations had actually seen the deep dweller.

The cave where the fish lives is named Fu Yuan Dong, which means Cave of Fortune.

A recent study has unveiled that the King demoiselle (Chrysiptera rex) is actually three different species that recently diverged from each other.  (picture)

“This work, along with others, is starting to show that there is a lot more biodiversity in the oceans then we previously thought,” said Joshua Drew, a marine conservation biologist at the Field Museum of Natural History in Chicago and a member of the demoiselle study. “We really are in a situation where we are losing things before we even know they exist.”

The King demoiselle comes in a wide range of colours and patterns, but this alone is not enough to consider it several species. There are plenty of examples of fish that look very dissimilar from each other while still belonging to the same species.

However, what Dews’ colleagues discovered while doing field research in Southeast Asia was that the differences in appearance seemed to be linked to distinct geographical regions. In order to find out more, they decided to ship about a dozen King demoiselle samples to Drew, collected from three separate populations in Indonesia, the Philippines and the South China Sea.

In his laboratory, Drew analyzed the genetic composition of the samples, focusing on three different genes – one that has evolved slowly and two that have changed quickly over the years. What Drew found out was highly interesting: the two fast changing genes differed in the three geographical groups, but not the one slow changing one. This indicates that from an evolutionary perspective, the three groups diverged from each other quite recently.

“That means that this little fish we thought was broadly distributed has a mosaic of individual populations and each one is genetically distinct,” Drew explained. “That highlights how little we really know about how biodiversity on Earth is distributed.”

Earlier, scientists assumed that it was difficult for distinct populations of reef fish to form if they had small larvae easily caught by currents. It seemed reasonable to presume that larvae from many different geographical locations would intermingle with each other throughout the sea. New data, obtained from studies like the King demoiselle one, do however suggest that larvae often settle close to its point of origin.

The King demoiselle study will be published in the journal Coral Reefs.

http://springerlink.metapress.com/content/100407/?p=32f929fa7f60452da6d63226ec8898a6&pi=0

For the first time, a viral hemorrhagic septicemia virus (VHSV or VHSv) has been identified in fish from Lake Superior, the largest of the five Great Lakes of North America.

The virus was identified by researchers at the Cornell University’s College of Veterinary Medicine and the finding has also been confirmed by the United States Geological Survey’s (USGS) Western Fisheries Research Center in Seattle.

The virus causes viral hemorrhagic septicemia (VHS) in fish and can result in significant losses in wild and captive raised fish populations.

“VHS is one of the most important diseases of finfish,” says James Winton, a VHSV expert working at the Western Fisheries Research Center. “It not only affects the health and well-being of populations of several important native fish species, but it can also impact trade, and, should it spread into the U.S. aquaculture industry, could do substantial damage as happened in Europe and parts of Japan.”

The infection is one of only nine fish diseases that must be reported to the World Organization for Animal Health. Until 2005 it was not known to exist in the Great Lake system but that year it caused several massive die-offs. Since then the virus has been detected in all of the Great Lakes except Lake Superior, and was for instance the culprit when 40,000 freshwater drums died in Lake Ontario over the course of just four days. In addition to the Great Lakes, the virus is also present in the rivers of Niagara and St. Lawrence and in inland lakes in New York, Michigan and Wisconsin.

Previous genetic research carried out by scientists in Canada and the United States show that the VHS virus was probably introduced to the Great Lakes during the last 5-10 years.

Experts now fear that current federal and state restrictions placed upon the movement of fish and fish products won’t be enough to prevent the virus from reaching native fish in the 31 states of the Mississippi River basin.

“Perhaps part of the reason the males are so likely to cheat is that females never punish males”, marine scientist says.

Male Labroides dimidiatus cleaner fish punish females that bite instead of clean (thus driving off the bigger fish) but females never punish males for doing exactly the same thing.

The Bluestreak cleaner wrasse (Labroides dimidiatus) lives on coral reefs where it feeds by removing parasites and dead tissue from the skin of larger fish. Most of the time the wrasse provides bigger fish with a valuable service, but sometimes the tasty mucus in front of the cleaner turns into an irresistible temptation, prompting the wrasse to bite off a mouthful. This is naturally not appreciated by the bigger fish and a cleaner wrasse who can’t control his or her urges will have to watch the big fish take off in a jiffy, taking all the nutritious parasites with it.

When a male fish notice a female fish scaring off the big fish they are cleaning together he will promptly punish her for her injudiciousness. This might seem altruistic, but the male fish is actually pissed off at her for making his dinner swim away.

“The male’s dinner leaves if the female cheats,” says Nichola Raihani from the The Zoological Society of London who has been studying Labroides dimidiatus together with research partner Redouan Bshary.

“By punishing cheating females, the males are not really sticking up for the clients but are making sure that they get a decent meal,” Raihani explains.

Raihani believes true altruism is rare.

“When you see something that looks like it’s altruistic, if you look hard enough, there’s normally going to be a benefit somewhere down the line for the person that’s doing that supposedly altruistic act,” she says.
Interestingly enough, a female fish that has to watch her dinner swim away because a male wrasse couldn’t leave the mucus alone never punishes the culprit.

“The males are less well behaved than the females a lot of the time but perhaps part of the reason the males are so likely to cheat is that females never punish males,” Dr Raihani told the Science podcast.

Males tend to be larger than females and this might be why the female finds it safer not to discipline him. All Bluestreak cleaner wrasses start out as females and in a group of 6-8 wrasses you will never find more than one male. If the male dies or is removed from the group, the strongest female will change into a male and take his place.

The wrasse study has been published in the journal Science.
You can download the podcast here: http://podcasts.aaas.org/science_podcast/SciencePodcast_100108.mp3

The red snapper population living in the Gulf of Mexico is showing signs of recovery, according to new information obtained by the National Oceanic and Atmospheric Administration of the United States (NOAA).

“The update showed harvest levels were still a bit too high in 2008; however, scientific projections are promising for 2009, indicating that the stock may improve enough to support higher harvest levels,” said Dr. Bonnie Ponwith, Southeast Fisheries Science Center director for NOAA’s Fisheries Service. “This is very exciting news and is evidence of how science and management can work together to protect our natural resources.”

In response to a rapidly dwindling red snapper population, the Gulf of Mexico Fishery Management Council began restricting red snapper fishing in the mid-1980s and in 2007 a catch share program was implemented for commercial fishermen.

“This has been our most challenging fishery issue in the Gulf of Mexico to date,” said Dr. Roy Crabtree, southeast regional administrator for NOAA’s Fisheries Service. “The Gulf Council deserves a lot of credit for making some very difficult decisions and commercial and recreational fishermen deserve equal credit for complying with the regulations to help this species recover.”

The red snapper in the Gulf of Mexico is managed separately from the population living along the coasts of North Carolina, South Carolina, Georgia, and eastern Florida. In December 2009, NOAA’s Fisheries Service announced a temporary rule to protect the red snapper along this coastline as the population is in poor condition, much like the Gulf of Mexico population used to be. The temporary rule will become effective today, January 4th.

For more information please see the NOAA News Release.

A transparent goldfish that reveals its inner organs has been developed by a joint research team of Mie University and Nagoya University in Japan.

The aim of the project was to create a transparent fish that makes it possible for researchers to study blood constituents and organ behaviour without having to dissect the animal. Unlike ordinary goldfish variants, this type has therefore been made really big and can weigh up to 1 kg. Up until now, the transparent fish of choice for researchers have been the see-through zebrafish, but this tiny fish only weigh abut 3 grams and is therefore much more difficult to study than the 1 kg goldfish.

The translucent goldfish was developed in just three years by repeatedly letting selected pale goldfish specimens mate with each other.

“Pale-colored goldfish have little commercial value, but their negative value has turned into a positive,” said Mie University Associate Professor Yutaka Tamaru.

The creation of a transparent goldfish was announced Wednesday last week at the annual meeting of the Molecular Biology Society of Japan.

An unusual road accident put traffic to a complete halt today on the E6 highway outside Strömstad on the Swedish west coast.

A truck loaded with sill herring offal dropped its smelly cargo after a tailgate had opened up as the truck passed over a speed bump. The fish offal flew out of the truck and into the grill of a passing truck, causing a complete engine failure.

No one was injured, says SOS Alarm, the Swedish Emergency Service, but the Swedish road administration expects the clean-up work to take several hours.

Herring
Herring is a fairly small oily fish native to shallow parts of the North Atlantic and Pacific Ocean, including the Baltic Sea. Herring has been an important part of Swedish cuisine for thousands of years and the fish is still served year round. Herring becomes especially sough after around Christmas and Midsummer when it is served in its traditional pickled fashion and chased down with hard liquor made from grain or potatoes. Herring caught in the Baltic Sea can also be fermented for 6 to 12 months to produce surströmming. Several airlines have banned canned of surströmming on their flights, deeming the pressurized containers a safety hazard.

Female scissortail sergants allow potential mates to fertilize a small batch off eggs and then monitor their parenting skills to decide if they are good enough to deserve a full clutch.

When studying filial cannibalism* in scissortail sergeants, ecologist Andrea Manica** of the University of Cambridge noticed that some females approached a male’s nest, deposited a small amount of eggs, and then left.

This aroused his curiosity and he decided to provide the males with ceramic tiles to use as nest sites. Once a female has deposited a small clutch on a ceramic tile, Manica either left the eggs alone or rotated the tiles to move the eggs.

The tiles that were left alone turned out to be popular; two-thirds of the females returned to deposit a full clutch of eggs later. The tiles that had been rotated by Manica were much less desirable and only a quarter of the females returned to lay a new batch.

Overall, this method of testing potential fathers seems to be rather rare in the population researched by Manica. Out of 421 females, only 7.4 percent laid test eggs before depositing a full batch. Manica also noticed that the method was used mainly at the onset of the breeding cycle. Later in the cycle, the amount of eggs already inside a nest seemed to suffice as indicator.

“The female fish probably use these test eggs when they don’t have much to go by. As a strategy, to me it makes lots of sense. There are probably lots of other species that do that,” said Manica.

The Scissortail sergant (Abudefduf sexfasciatus) is a large damselfish native to coral reefs in the Indo-Pacific. Also known as the Striptailed damselfish, it can be recognized on its black striped tail and sides. In this species, the eggs are cared for by the male fish who must not only resist the urge to eat his own offspring but also be brave and skilled enough to protect them from being eaten by other predators.

The study has been published in Animal Behaviour.
http://www.elsevier.com/wps/find/journaldescription.cws_home/622782/description#description

* Filial cannibalism is when an adult eats the young of its own species. In many species of fish, adults won’t hesitate to eat even their own immediate offspring.

** http://www.zoo.cam.ac.uk/zoostaff/manica.html