Giant fish-eating spiders reintroduced to British countryside

From TravelAol.co.uk:  Giant fish-eating spiders reintroduced to British countryside


Arachnophobes may want to look away now... ecologists have released hundreds of the UK's largest breed of spider into the wild - and they can grow up to 8cm long.

The great raft spider has been saved following a breeding programme in 10 zoos, that saw thousands of spiderlings being reared for reintroduction to their former base in the Norfolk Broads.

This arachnid is so big is it capable of catching and eating a fish as it glides across the water, according to the Daily Mail.

But, before you scream in horror, these spiders only live in wetlands, so you won't be finding them in your living room anytime soon.

Around 200 baby spiders have already been released at the RSPB's Strumpshaw Fen reserve near Norwich.

SWNS

Bristol Zoo Gardens keeper Carmen Solan raised 170 of the arachnids, using a special tube operated with her mouth to feed the tiny babies dead flies.

The ecologist, who has been working with fen raft spiders for 20 years, said the conservation programme is mainly concerned with giving the spiders the best chance in the wild, according to the BBC.

By rearing the spiderlings in isolation, project staff can boost their survival rates by as much as 90%, which in turn gives them a greater chance of success in the wild.

 

Coming Soon: Robot Sea Turtles That Carry Cargo in Their Shells

From Pop-Sci:  Coming Soon: Robot Sea Turtles That Carry Cargo in Their Shells

Turtlebot One of the concept designs for the naro-tartaruga robot looks like a full-size sea turtle. ETH Zurich

The makers of quadrocopters and other fun robots at ETH Zurich may be landlubbers, but that does not stop them from designing objects that swim. The Swiss students are working on a turtle-inspired bot that can swim with efficiency while carrying plenty of cargo. The Naro-Tartaruga may not be as glide-y as a fish or eelbot, but it might be easier to build, and it is better for carrying payloads and robot parts like batteries and controllers.
As of now, the robot is a cylindrical aluminum vessel with turtle-inspired flippers, which will help it propel itself through the water. Concept designs include the more realistic-looking turtlebot seen above. The research team at ETH Zurich started with a tuna in 2008, studying how to imitate its movement in water. The main goal is to pick a winner between flapping fins and propellers. Whichever is more efficient could power new generations of ocean-inspired underwater autonomous vehicles.

Naro-Tartaruga:  ETH Zurich via Facebook

 

Researchers: Preserving Old Female Cods Key To Population Conservation

From Underwater Times: Researchers: Preserving Old Female Cods Key To Population Conservation

GOTHENBURG, Sweden -- Cod are among Sweden's most common and most popular edible fish and have been fished hard for many years. One consequence is the risk of serious changes in cod stocks, reveals research from the University of Gothenburg, Sweden. In overfished areas, there is often a shortage of large and old cod, and the fish become sexually mature at a younger age. Researchers have feared that this change may have impacted on the fish's health, physiological aging and reproductive capacity.

In a recently published study, a research group from the University of Gothenburg working with the Swedish University of Agricultural Sciences therefore looked into the health and aging of male and female cod.

"We measured various aspects of oxidative stress, a condition in the cells that can lead to irreparable damage, antioxidant capacity, which protects against oxidative stress, and telomere length," says researcher and marine biologist Helen Nilsson Sköld.

Telomeres are repeated DNA sequences that protect the ends of chromosomes. The length of these telomeres and the rate at which they get shorter are closely linked to health and aging.

The researchers compared the health of cod in the Öresund, Skagerrak and Kattegat. Cod in the Öresund have been protected from trawling since 1932 and so stocks include larger and older fish, but cod in the Skagerrak and Kattegat have been seriously overfished.

"Our results show that older males generally have shorter telomeres and a reduced antioxidant capacity," Helen Nilsson Sköld explains. "However, we didn't see the same pattern among females -- there were no signs of physiological aging in the age span we looked at for the females (two to eight years)."

The researchers were surprised to see such marked gender differences. Although older males were fatter and seemed less stressed than younger males, the females were generally in better shape than the males.

"Our theory for why the males age and are more stressed during spawning is that they have to compete for territory and mates. This stress seems to be more acute among the younger males."

The researchers were unable to find any signs of the overfished stocks of the Skagerrak and Kattegat being less healthy than the Öresund population.

A key factor in this context is that larger fish produce a much higher number of eggs -- it can vary from half a million to five million depending on the size of the cod.

"Our study also shows that large older females are healthy and don't seem to have aged physiologically," Helen Nilsson Sköld adds. "The conclusion is that it's important to look after the large older females, as they produce many more eggs than younger ones. A conservation strategy of this kind would be ideal in the Skagerrak and the Kattegat."

How do fish know if they're swimming in the right school?

From ABC Science:  How do fish know if they're swimming in the right school?

ish can't see themselves, or use a mirror! How do they know they are in the right school of fish?— Jim
Almost 80 per cent of the more than 20,000 known fish species school at some point in the life cycle.
Schooling helps reduce the risk of being attacked by predators, and also makes swimming easier because the fish position themselves so they are able to slipstream in their neighbours' wake.
Some species school only when they are vulnerable juveniles, others when they are older. They begin by swimming in pairs and then in larger and larger groups of the same species.
While fish have big eyes to help them find prey and keep track of each other up close, they rely on their chemosensory system to track other fish of the same species in the vastness of the ocean, says Dr Ashley Ward, a fish biologist at the University of Sydney.
"A fish can smell itself, and recognises others with the same smell," says Ward, who studies the social behaviour of fish.
Fish use smell to sniff out a partner with a strong immune system.
The smell of an individual fish is genetically programmed by major histocompatibility complex (MHC) molecules, which are crucial to vertebrate animals' immunity to disease.
"As a by-product, MHC affects the way we and other vertebrates smell," explains Ward.
"Even though all the fish in a school may look alike, when it comes to choosing a mate, picking one that smells different, that is, not related, will ensure the resulting offspring will have the best range of immune responses."
But when it comes to choosing who to hang out with, the smell of where a fish lives and what it eats is even more important.
"Like humans, who take on smells from our diet such as garlic or asparagus, fish clearly smell which individuals live in their microhabitat and preferentially associate with them," says Ward.
"We think the reason that they can do this is that another individual which carries that 'local' smell might have important local knowledge," he says.
But the way they smell, and their ability to smell each other can be affected by chemicals introduced into the aquatic environment.
"Water pollution might mean they have trouble recognising their school or potential mates," says Ward.

Fishy frenemies

Fish are pretty picky when it comes to choosing their school friends.
"Shoaling (schooling) fish have a strong preference for associating with familiar over unfamiliar fish.
"If territorial or solitary, they recognise their neighbours and are less aggressive to them than outsiders. And when it comes to mating, promiscuous fish recognise and avoid the ones they have mated with previously," says Ward.
Less well-proven, he says, is the way fish choose foraging companions. Recognising their foraging companions' strengths and weaknesses may be the difference between finding a meal, and ending up as one.
Some recognise poorer competitors and prefer to associate with them, he says, presumably because they know they will end up with a bigger share of the day's catch, while others show a preference for good foraging companions from the past.
"This might be those that forage better, are better navigators or are skilled at avoiding predators," Ward says.
"It has also been shown that fish have personalities, and exhibit certain types of behaviour, where they may be either bold or shy.
"While they may look alike, groups comprising a diversity of personality types, that is a mix of bold and shy fish, have been shown to outperform those composed of one type."

 

California Names Leatherback Sea Turtle As Official State Marine Reptile

From Underwater Times: California Names Leatherback Sea Turtle As Official State Marine Reptile

SACRAMENTO, California -- In a strong affirmation of the Golden State's commitment to the environment, Governor Brown today designated the endangered Pacific leatherback sea turtle as California's official state marine reptile by signing into law Assembly Bill (AB) 1776 by Assemblymember Fong (D- Cupertino). As sponsors and supporters of the bill, SeaTurtles.org and Oceana applaud Governor Brown and the State Legislature for providing a first of its kind recognition of the importance of this critically endangered species to the state's marine ecosystem.

Leatherback sea turtles are best described by superlatives: they are an ancient lineage outsurviving the dinosaurs; they are the largest sea turtle on Earth; they can dive to a depth of over half a mile,-- as deep as the giant whales; they have one of the longest migrations of any animal (6,000 miles across the entire Pacific), and unfortunately, are the most endangered sea turtle in the Pacific due to incidental capture in industrial fishing drift nets and longlines.

Per the new state law, October 15, 2013 will be California's first annual Leatherback Conservation Day. Schools will be encouraged to teach students about this centuries-old sea turtle species that makes an incredible 6,000 mile journey from Indonesia to the California coast to feed on jellyfish.

"By designating the Pacific leatherback sea turtle as our state marine reptile, California joins a coordinated worldwide conservation effort," said Assemblymember Fong, who introduced the bill. "This bill demonstrates California's commitment to protecting our ocean's ecosystem and a species whose population has declined more than 95 percent and whose migratory pattern includes California's coast."

"California has now established itself as a national leader in promoting conservation of Pacific leatherbacks, which have survived in the Pacific Ocean for over 100 million years but are now being driven to extinction by fisheries bycatch, poaching, and plastic pollution," said Dr. Chris Pincetich, marine biologist with www.SeaTurtles.org, the primary architect and sponsor of AB 1776."I can now imagine that in the near future I will be able to visit a California classroom and all the students will have learned about leatherbacks, their critical habitat offshore, and ways they can take action to ensure their continued survival. Right now, students that have even heard of them are in the minority."

More than 16,000 square miles of California's coastal waters were designated as critical habitat for leatherbacks earlier this year. However, more needs to be done as the most recent nesting surveys are showing continued declines for the population that utilizes California waters. This new law will encourage state and federal agencies to build cooperative relationships with island nations where Pacific leatherback sea turtles return to nest in order to increase awareness and conservation of this critically endangered species.

"By recognizing the Pacific leatherback as the newest state symbol, Governor Brown continues California's leadership in ocean conservation," said Ashley Blacow, Oceana's Pacific Policy and Communications Coordinator. "Pacific leatherbacks are on the brink of extinction, and public awareness is a key ingredient to turning the tide for these ancient marine reptiles."

"Governor Brown's action today will help us to educate, motivate and most importantly, actualize more concrete measures to protect the critically endangered Pacific Leatherback from extinction," said Todd Steiner, biologist and executive director for www.SeaTurtles.org.

Divers flock to see rebound of Goliath grouper

From the Miami Herald:  Divers flock to see rebound of Goliath grouper

JUPITER -- The huge Goliath grouper seemed to be playing peek-a-boo with divers hovering near the wreck of the MG III about 60 feet deep off Jupiter. If the humans swam too close, the giant mottled brown fish backed up deeper into the shipwreck. But if they held still and waited, it edged closer — cocking its head to eye them, then opening its cavernous maw so that they could see all the way down to its palate.
Not far away, some other divers creeping up on scores of Goliaths puttering around the wreck heard a deep boom that sounded like an orchestra tympani or the penetrating bass of a rap song. That meant the humans were invading the fish’s space, and it was warning them off using vibrations from the muscles attached to its swim bladder.
Far from scared, the divers were elated.
“That was so cool,” they told one another after surfacing at their charter boat, the Blue Tang.
In a two-tank drift dive that covered three 90-foot-deep artificial reefs — the Zion, Miss Jenny and Bonaire — followed by the shallower MG III, the dozen divers probably had observed several hundred Goliath groupers. Large schools of the huge, gentle giants began showing up on shipwrecks from Boynton Beach to Stuart in July for their annual spawn, which peaked in August and is expected to extend into mid-October.
Scuba divers come from Florida, the United States and around the world just to see the one-of-a-kind aggregation of huge fish now making a resurgence after nearly being wiped out by overfishing in the 1980s. Since the Goliath fishery’s closure in the South Atlantic and Gulf of Mexico in 1990, the population has swelled, prompting some spearfishers and hook-and-line anglers to call for its reopening.
But NOAA Fisheries, the federal agency in charge of managing fish stocks in the United States, and the Florida Fish and Wildlife Conservation Commission have no plans to open the harvest of Goliaths anytime soon. Scientists from the two agencies are expected to begin a stock assessment in 2015 to determine whether they have rebounded enough to allow any take. Chris Koenig, a retired professor from Florida State University, and several colleagues are gathering scientific data for that assessment. A lot of their work is performed in the waters around Jupiter.
“It’s neat they aggregate in such density,” Koenig said. “You can’t see that anywhere in the world. Now the population is really building. They’re doing well. They’re getting up there.”
Koenig and his fellow scientists are trying to learn all they can about the giant groupers’ life history, movements, reproduction and diet. They have caught, tagged, sampled and released more than 400 Goliaths off Jupiter in the past two years — including a banner weekend of 80 in three days earlier this month.
Working from captain Mike Newman’s commercial boat, Dykoke, the scientists use heavy lines dangling from poly balls and circle hooks baited with chunks of barracuda, jack, and bonito to catch Goliaths on the wrecks. They handline the fish quickly into the Dykoke’s cockpit and pump saltwater through its gills while they take a sample of the fin rays for aging, biopsy the ovaries and collect sperm, pump the stomach to see what it ate, collect genetic material, and implant streamer and acoustic tags. Occasionally, a fish dies after being worked up, which upsets divers who find it.
But Koenig said his team has lost only three fish in two years — a tiny percentage of the 800 that federal and state fisheries managers considered allowing them to kill five years ago in order to take otoliths, or ear bones, for aging. Koenig said they don’t need to harvest fish because they’ve developed non-lethal techniques for sampling.
Since the mid-1990s, Koenig said, scientists have learned a lot about Goliaths:
• They eat mostly small, slow-moving fish and crustaceans, but very few lobster.
• They are hermaphrodites, harboring sperm and eggs in the same set of gonads in 5-10 percent of fish sampled.
• They can live to their 60s, beginning to spawn at about four feet long.
• As juveniles, they inhabit mangrove estuaries then move out to deeper water when they mature.
• They will travel long distances — as much as 180 miles — to reach summer spawning sites.
Unknowns include: Do the fish spawn in pairs or groups? Can larvae harvested during spawning be raised in captivity? And what is the exact relationship between size and age?
Koenig urges anglers eager to target Goliath grouper to be patient and accept the findings of scientists.
“I get sick of arguing about it,” Koenig said. “All this misinformation they repeat to each other until it becomes truth. People believe their buddies and not what science tells them. They want their cake now. It’s hard getting through to them.”

Read more here: http://www.miamiherald.com/2012/09/27/3022594/divers-intrigued-by-goliath-grouper.html#storylink=cpy

Read more here: http://www.miamiherald.com/2012/09/27/3022594/divers-intrigued-by-goliath-grouper.html#storylink=cpy

 

Whale hunt to go on, despite ship refit

From The Australian:  Whale hunt to go on, despite ship refit

JAPAN'S Fisheries Agency says plans to refit its ageing factory ship Nisshin Maru won't stop it launching this year's Antarctic whaling hunt. 
 
The ship used every year on its whaling expeditions needs a major overhaul in the hope of getting at least another decade's service out of it, the agency says.

But it stressed the refit will be finished in time for this season's hunt, controversially carried out under the banner of “scientific” whaling.

“As research whaling is important, we'd like to conduct major repairs (on the ship) so that it can be used for at least 10 years,” said Tatsuya Nakaoku, the official in charge of whaling.

The agency is studying with shipbuilders how long the refitting will take, but “there is no possibility” that Japan will miss the voyage this year, he said.

Whales are caught by relatively nimble harpoon ships that bring their catch back to the larger Nisshin Maru, where the mammals are butchered and processed, before being chilled.

The Fisheries Agency's comments came after a report in the daily Asahi Shimbun, which said it was considering abandoning its controversial mission this season because of the refit.

The Asahi said the idea of there being no hunt this year had met with opposition from politicians, afraid a disruption for even one year would make Japan look “weak-kneed”.

Japan's whaling mission departs in November, or later, and comes home in the northern spring the following year.

Commercial whaling is banned under an international treaty but Japan has since 1987 used a loophole to carry out “lethal research” on the creatures in the name of science.

It has infuriated Australia and New Zealand, which say it is a fig leaf for commercial whaling. The Japanese fleet is pursued every year by anti-whaling group Sea Shepherd.

Japan claims the hunt is necessary to substantiate its view that the world had a robust whale population. But it makes no secret of the fact that whale meat from this research ends up on dinner tables and in restaurants.
Anti-whaling activists have cut the number of animals Japan was able to harpoon to 267 in 2011-2012, less than a third of the intended haul.

In the preceding season, Japan cancelled the hunt after killing only 172 whales because of harassment by environmentalists.