Sharks can be trained like dolphins to feed from keepers, roll over and enjoy cuddles, according to new research.
In experiments carried out in the US some varieties of shark allowed
themselves to be picked from the water and cuddled.
Keepers at the UK's Sea Life Centres will now use the training techniques in
the hope that they will end up with hundreds of trained sharks.
The experts at the aquariums are to begin a period of intensive tuition by
using coloured boards and sounds to train the sharks in a similar way to
that used by the scientist Ivan Pavlov in training dogs.
It will mean that feeding becomes easier because each shark in a tank will
know when it is their turn to feed.
The Sea Life centres have many different types of shark and within just three
months the brightest ones should be responding to commands.
Sharks learn the signals then, when they see or hear them, they approach the
keeper who holds a "target stick".
The sharks then rub their noses against the stick and wait until they are fed.
No one had attempted to train sharks in this way before, but it could now
teach experts a great deal about the creatures.
Carey Duckhouse, of Sea Life, said: "The US team has shown that many
varieties of sharks can quickly learn to respond to a combination of audible
and visual signals.
"A shark answers its own sound and colour signal by putting its nose on a
target-stick held by the trainer, and keeping it there until it receives
food.
"Some species, such as zebra sharks, will even roll over to have their
tummies scratched or allow themselves to be lifted from the water without
any kind of struggle.
"The implications for improving shark welfare are enormous. It means when
we have to move them we can get the sharks to swim to a certain spot rather
than have to chase them around."
Taken off the coast of Mexico's Holbox Island by amateur photographer Sandra Critelli, this breathtaking picture captures the migration of thousands of rays as they follow the clockwise current from Mexico's Yucatan peninsula to western Florida.
Measuring up to 6ft 6in across, poisonous golden cow-nose rays migrate in groups - or 'fevers' - of up to 10,000 as they glide their way silently towards their summer feeding grounds.
These cow-nose rays (Rhinoptera bonasus) have distinctive, highdomed heads, giving them a curiously bovine appearance.
But even equipped with this powerful poisonous stinger, cow-nose stingrays are shy and non-threatening in large 'fevers'. Even when isolated, they will attack only when cornered or threatened.
Unlike other stingrays, they rarely rest on the seabed (where unsuspecting humans can step on them) and prefer to be on the move.
They migrate long distances, and can be found as far south as the Caribbean and as far north as New England.
They use their extended pectoral fins to swim, and often turn upside down, curling their fin tips above the surface of the water - leaving terrified swimmers convinced that they have seen a shark. :)
Their flexible fins also come in handy when rustling up food. By flapping them rapidly over the seabed, they stir up sand and reveal crabs, shellfish and oysters, which they then feed on using their powerful, grinding teeth.
Their particular fondness for shellfish has made them public enemy number one with oyster fishermen.
But despite this, their numbers are exploding, thanks in part to rising sea temperatures. They mate every winter, and females produce a litter of five to ten young.
Critelli said: ' It was an unreal image, very difficult to describe. The surface of the water was covered by warm and different shades of gold and looked like a bed of autumn leaves gently moved by the wind.'
The research team, writing in the science journal PLoS One, said they repeatedly observed a female dolphin herding cuttlefish out of algal weed and onto a clear, sandy patch of seafloor.
The dolphin, then pinned the cuttlefish with its snout while standing on its head, before killing it instantly with a rapid downward thrust and "loud click" audible to divers as the hard cuttlebone broke.
The dolphin then lifted the body up and beat it with her nose to drain the toxic black ink that cuttlefish squirt into the water to defend themselves when attacked.
Next the prey was taken back to the seafloor, where the dolphin scraped it along the sand to strip out the cuttlebone, making the cuttlefish soft for eating.
"It's a sign of how well their brains are developed. It's a pretty clever way to get pure calamari without all the horrible bits," Mark Norman, the curator of molluscs at Museum Victoria.
A separate 2005 study provided the first sign dolphins may be capable of group learning and using tools, with a mother seen teaching her daughters to break off sea sponges and wear them as protection while scouring the seafloor in Western Australia.
Neither British colonists nor Christian missionaries nor government entities could tamp down conflicts among tribes in this remote South Pacific island nation. But when turtles started disappearing, the local people finally started talking.
The Solomon Islands, a remote Pacific archipelago strung southeast of Papua New Guinea, are probably best known as the site of the World War II Battle of Guadalcanal. But they also contain some of the world’s most important nesting grounds for hawksbills. On these beaches, the turtles haul their 150-pound bodies out of the surf and bury hundreds of thousands of eggs in the crushed-coral sand. For the hatchlings that survive, this becomes their hard-wired home, the place to which they’ll return to lay their own eggs.
The Arnavons Community Marine Conservation Area—encompassing 40,000 acres, three small uninhabited islands, flourishing reefs, fish-filled lagoons and beaches that are home to thousands of egg-bearing turtles—is run by an improbable cast of characters. A band of reformed arsonists, poachers and unreformed turtle eaters has teamed up with the Solomon Islands government and The Nature Conservancy to reimagine conservation around their own worldview. At the heart of the project are three communities on Choi-seul, Santa Isabel and Waghena islands—a mix of tribes and cultures who argued over the use of the neighboring Arnavon Islands until agreeing on no use.
This is the first community-run marine protected area in the South Pacific. Now going on 12 years, the project is showing that well-managed protected areas promote healthy communities of turtles and other marine life and also improve the lives of human communities. And a recent anonymous gift to the Conservancy has completed an endowment that will provide sustainable financing for the project—a first for a marine protected area. Says Zama, “It’s up to the three of us [communities] now.”
To fully appreciate the significance of this peaceful arrangement, it helps to understand the violent history that serves as its backdrop.
..
“Nowadays we only eat turtles for feasts,” Bako says. “It is our kastom.” Such customary feasts are long-standing traditions in Pacific island nations. A turtle on the table for an important birth, death or religious holiday in the Solomons is the equivalent of a Thanksgiving turkey. And in a country where 85 percent of the population depends entirely on natural resources, turtles—even endangered ones—remain an important part of the subsistence diet.
The British colonial government in 1963 resettled the people of the Gilbert (now Kiribati) Islands to the Solomons. The Gilbertese built a village on Waghena, which put the newcomers closer to the Arnavons—and the islands’ abundant marine resources—than either indigenous community on Choiseul or Isabel. Inter-island resentment intensified, and the communities again were in conflict—this time arguing over claims to the Arnavons. The Gilbertese were being blamed for the depletion of resources.
“Some people, when they harvest, they don’t have a controlled harvest,” says Bako. “It’s like a sport: Who will be the champion?”
Edward mayer and Susan Brown are like marriage counselors for conservation. They help partners hash out differences, build trust and collaboration, and cultivate common interests. In 1993, when the Conservancy first entered the picture in the Arnavons, its goal was to get stakeholders talking.
And it took lots of talking before the landowners on Choiseul and Isabel were willing to welcome Waghena residents as a full project partner. Yet it was “the Gilbertese who had the most to lose from the formation of the conservation area,” says the Conservancy’s Thomas. “It is to their credit that they came to the party.” Once they did, the group set up a management committee for the Arnavons Community Marine Conservation Area. The committee was made up of two representatives from each community, three government representatives and Mayer, who tried not to say much. “A lot of the dynamic,” he says, “had to do with how open we were to listening.” Mayer emphasizes the value of consensus among the communities.
As for the three communities on Choiseul, Isabel and Waghena, disputes over the Arnavons may never be fully resolved. But leaders of all three communities seem willing to look beyond those differences for the good of the whole.
Most Marine protected areas (MPAs) are designed to contain zones with different uses that preserve and enhance recreational, commercial, scientific, cultural and conservation goals. Often, their main purpose is to reduce or eliminate harmful extractive activities, such as overfishing.
Scientific evidence shows that MPAs can help preserve and increase the overall diversity and abundance of marine species. By creating networks of MPAs, the Conservancy aims to ensure that ocean and coastal habitats have a better chance of surviving catastrophic events, such as warming waters that bleach corals.
Photographer Jeff Yonover shot these jaw-dropping underwater images (slideshow) in many of the places The Nature Conservancy works — Kimbe Bay and New Britain Island of Papua New Guinea as well as the Solomon Islands. (Natural Light Photos)
From Nature News.
A pack of killer whales uses waves to knock seals off the ice.
They made large waves to wash the seal off the relative safety of the ice. Later the orca put the seal back on the ice and dislodged the seal a second time which suggested strongly they were training their young.
It is not the first time a complex behaviour has been seen in just a few orcas. In the early 1970s, an orca was seen in Argentina beaching itself next to seals. At first it seemed to be in distress, but then it lunged at seals nearby, grabbed one by the neck, and dragged it back into the water. This beaching hunting technique has since been observed hundreds of times in Argentina among a small group of orcas. Studies have shown that the orcas can time their forays onto land to coincide with the tides, so they run less risk of becoming permanently beached.
Both the beaching and the wave hunting seem to be techniques that pod elders teach to younger animals. The Argentinean orcas have been seen nudging youngsters onto the shore, encouraging them to try the tactic, often coming up alongside to demonstrate. In the group at the Antarctic Peninsula, young orcas are often present during the hunt, and adults sometimes put living seals back on the ice after catching them, seemingly so that the young can have another try.
“This is orca culture,” says Visser.
Captured just before midnight on November 13 by fishers in Cambodia, this Mekong giant catfish is 8 feet long (2.4 meters long) ands weighs 450 pounds (204 kilograms).
"This is the only giant catfish that has been caught this year so far, making it the worst year on record for catch of giant fish species," said Zeb Hogan (far right), a fisheries biologist at the University of Reno in Nevada.
After collecting data on the fish, Hogan released it unharmed.
Giant catfish were once plentiful throughout Southeast Asia's Mekong River watershed, including the Tonle Sap River—home of the fish in these exclusive pictures taken near Phnom Penh.
But in the last century the Mekong giant catfish population has declined by 95 to 99 percent, scientists say. Only a few hundred adult giant catfish may remain.
Earlier this year Hogan launched the three-year Megafishes Project to document the world's giant freshwater fish.
Listed as critically endangered by the World Conservation Union, the Mekong giant catfish is big but toothless, as shown in this exclusive photo.
"For the Mekong giant catfish, northern Thailand is a spawning ground, whereas the Tonle Sap Lake in Cambodia is a rearing area," said U.S. biologist Zeb Hogan, who studied the fish pictured for his Megafishes Project, which is documenting the world's giant freshwater fish.
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