Friday, 23 September 2016

Asian hornet has arrived in Britain, government confirms, and could destroy precious resources

The insects wait outside bees’ hives and bites their heads off as they emerge so that they can steal honey
 
Andrew Griffin


Tuesday 20 September 2016

The first Asian hornets have been spotted in Britain and could be about to cause huge damage to bees, one of our most precious resources.

The hornets pose no risk to human health. But they pose a huge risk to the life of honey bees, one of our most precious and threatened natural resources.

Authorities are now launching a plan to find and destroy any nests belonging to the species, in an attempt to wipe them out in the UK.

Honey bees are in decline and are central to the life of many of the crops we use to feed ourselves. But the hornets pose a huge risk to them – waiting outside their hive’s entrance, biting their head off to kill them, getting rid of the entire group and then stealing their honey.

Our own bee colonies haven’t evolved to cope with the threat of attack from the hornets, and so could be at risk from them.

The hornets have long been the subject of worry in the media that the “killer” insects would make their way to British shores. That has now been confirmed after one was spotted in Gloucestershire, the government has said.
 
The hornets have become widespread in central and southern France. For years, authorities have worried that they could arrive in imported plantpots, timber or even flying over themselves.


Continued..

Norway plans to cull more than two-thirds of its wolf population


Environmental groups criticise plan that will allow hunters to shoot up to 47 of an estimated 68 wolves living in wilderness


Fiona Harvey Environment correspondent

Friday 16 September 2016 18.53 BST Last modified on Friday 16 September 2016 22.49 BST

Norway is planning to cull more than two-thirds of its remaining wolves in a step that environmental groups say will be disastrous for the dwindling members of the species in the wild.

There are estimated to be about 68 wolves remaining in the wilderness areas of Norway, concentrated in the south-east of the country, but under controversial plans approved on Friday as many as 47 of these will be shot.

Hunting is a popular sport in the country. Last year more than 11,000 hunters applied for licences to shoot 16 wolves, a ratio of more than 700 applicants to each licence.

The government has justified this year’s planned cull – the biggest in more than a century – on the basis of harm done to sheep flocks by the predators. Environmental groups dispute this, saying the real damage is minimal and the response out of all proportion.

The government did not reply to a request from the Guardian for comment.

The government has taken action to prevent illegal wolf hunting. Wolves are also an attraction for some tourists to the country. But the new legal hunting limit is beyond anything that the wild population can withstand, according to Norway’s leading green groups.

Under the arrangements, 24 wolves will be shot within the region of the country designated for wolf habitat, while another 13 will be shot in neighbouring regions and a further 10 in other areas of the country.

According to environmental groups, the number of wolves the government plans to kill this year is greater than in any year since 1911.

Creepy Cannibals: Squid Have No Qualms About Eating Their Own Kind

By Laura Geggel, Senior Writer | September 22, 2016 11:12am ET

The deep-sea diving Gonatus squid has a hearty appetite, even when it comes to eating its own kind, a new study finds.

The cannibalism finding came about during a 20-year study (1995–2015) in which marine researchers used a remotely operated vehicle (ROV) to study and video-record the eating habits of more than 100 different squid of the Gonatus genus in Monterey Submarine Canyon, off the California coast.

In particular, two species of Gonatus squid — Gonatus onyx and Gonatus berryi — showed a voracious appetite for munching on their own species, the researchers said. In fact, after looking at video they took of 109 squid eating meals, researchers found 42 percent of the prey G. onyx ate were other G. onyx squid. 
 
In addition, the researchers — Henk-Jan Hoving, an evolutionary ecologist of Marine Fishes at the Helmholtz Centre for Ocean Research Kiel in Germany, and Bruce Robison, a senior scientist and midwater ecologist at the Monterey Bay Aquarium Research Institute (MBARI) in California — never observed G. onyx feeding on G. berryi, but G. berryi routinely fed on G. onyx
 
Why cannibalism?
Cannibalism isn't uncommon in the deep sea, but this is the first time that scientists have proof that Gonatus squid engage in cannibalistic behavior, the researchers said.

They stressed the importance of having live-video evidence (in addition to stomach contents) of the cannibalism, since looking only at stomach contents of squid caught in trawling nets can be misleading. That's because squid and other marine creatures in trawling and jigging environments often become stressed and engage in unnatural behaviors, including cannibalism.

Though ROV lights and noises may also disturb marine creatures, in this study the researchers found that most of the prey capture happened before ROV the arrived, the researchers said.

Read more

Freshwater stingrays chew their food just like a goat


Date: September 16, 2016
Source: University of Toronto
 
A new University of Toronto study has found that some freshwater stingrays from the Amazon chew their food in a similar fashion as mammals.

Using a combination of high-speed video and CT scans Matthew Kolmann, a recently graduated PhD in the lab of U of T Scarborough's Nathan Lovejoy found that as the freshwater stingray Potamotrygon motoro eats it protrudes its jaws away from its skull, shearing from side to side in the process.

"It's pretty extraordinary when you think about it -- here's this bizarre-looking fish from the Amazon that evolved these behaviors separately from mammals, but chews its food just like a cow or a goat," he says.

Kolmann was first drawn to the question of how P. motoro and its close relative, Potamotrygon orbignyi, eat their prey after finding out both species feed on aquatic insects, unique for a family that also includes sharks, skates and other stingrays.

Stingrays have fins that encircle their head called a disk. They catch prey by lifting up the front part of their disk, which draws water and prey underneath, much like a suction cup. Once rays have trapped their prey, they grab it by rapidly protruding their jaws, shredding and tearing it apart.

"They don't actually use their mouth to catch their prey, which suggests that parts of the mouth can evolve away from that specific purpose and may be driving the novelty of this chewing behaviour," Kolmann says.


Read on

Cuttlefish number sense better than a one-year-old human, research shows




Findings suggest that the cephalopods – which have the most complex brains of any invertebrate – also prefer quality over quantity when it comes to food


Friday 9 September 201621.00 BSTLast modified on Friday 9 September 201621.01 BST

New research suggests cuttlefish can not only count better than a one-year-old human, but they also prefer quality over quantity when it comes to food.

A study of 54 one-month-old cuttlefish hatched in captivity was carried out by Tsang-I Yang and Chuan-Chin Chiao, researchers at the National Tsing Hua University in Taiwan.

Their findings suggest that cephalopods count potential prey such as shrimps, crab and fishes, and make several judgment calls in deciding whether or not to strike.

Presented with different numbers of live shrimp, the cuttlefish showed consistent preference for the larger quantities, suggesting they had “number sense”.

The researchers also found that the density of the group of the shrimp did not affect their decision, and that cuttlefish took longer to decide when the numbers were higher.

This indicated that the cephalopods were taking time to count the individual shrimp of each option, rather than making an assessment at a glance.

They pointed to similar studies of one-year-old humans, which found that babies could distinguish between one and two items, and two and three items, but no higher. Rhesus macaque monkeys could judge quantities of only up to four.

With cuttlefish able to distinguish between one and five and four and five, the researchers concluded that they “are at least equivalent to infants and primates in terms of number sense”.

Given the choice between one live shrimp and two dead shrimp, the cuttlefish also opted for the smaller quantity.

The researchers were particularly struck by their response to the choice between one large live shrimp and two small live shrimps, which depended on the state of their appetite.


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