Earth ChangesS


Bizarro Earth

Bizarre Bird Behavior Predicted by Game Theory

Raven
© UnknownRaven

A team of scientists, led by the University of Exeter, has used game theory to explain the bizarre behaviour of a group of ravens. Juvenile birds from a roost in North Wales have been observed adopting the unusual strategy of foraging for food in 'gangs'. New research, published in the journal PLoS One (on Wednesday 25 February 2009), explains how this curious behaviour can be predicted by adapting models more commonly used by economists to analyse financial trends.

This is the first time game theory has been used to successfully predict novel animal behaviour in the real world. The researchers believe this analysis could also shed light on the variation in feeding strategies in different populations in other species.

Butterfly

British Butterfly Reveals Role of Habitat for Species Responding to Climate Change

Most wild species are expected to colonise northwards as the climate warms, but how are they going to get there when so many landscapes are covered in wheat fields and other crops? A study published today (Wednesday 25 February 2009) shows it is possible to predict how fast a population will spread and reveals the importance of habitat conservation in helping threatened species survive environmental change.

Published in the journal Proceedings of the Royal Society B, the research tracks the recovery of a rare British butterfly over 18 years and offers hope for the preservation of other species.

Conducted by the Universities of Exeter, York and Sheffield and funded by the Natural Environment Research Council, the study could inform future conservation policy to help safeguard vulnerable species against the effects of climate change and habitat destruction.

Magnet

Florida tests using magnets to repel crocodiles

Florida wildlife managers have launched an experiment to see if they can keep crocodiles from returning to residential neighborhoods by temporarily taping magnets to their heads to disrupt their "homing" ability.

Researchers at Mexico's Crocodile Museum in Chiapas reported in a biology newsletter they had some success with the method, using it to permanently relocate 20 of the reptiles since 2004.

"We said, 'Hey, we might as well give this a try," Lindsey Hord, the Florida Fish and Wildlife Conservation Commission's crocodile response coordinator, said on Tuesday.

Crocodiles are notoriously territorial and when biologists move them from urban areas to new homes in the wild, they often go right back to the place where they were captured, traveling up to 10 miles a week to get there.

Scientists believe they rely in part on the Earth's magnetic fields to navigate, and that taping magnets to both sides of their heads disorients them.

"They're just taped on temporarily," Hord said. "We just put the magnets on when they're captured and since they don't know where we take them, they're lost. The hope would be that they stay where we take them to."

Fish

Fish has transparent head

Scientists in California have filmed a fish with a transparent head.

And the encounter has helped researchers solve the 50-year-old mystery of how the fish uses its extraordinary eyes to see in the gloomy ocean depths.


Better Earth

First evidence of a supernova in an ice core

supernova
click to enlarge

There hasn't been a decent supernova in our part of the universe in living memory but astronomers in the 11th century were a little more fortunate. In 1006 AD, they witnessed what is still thought to be the brightest supernova ever seen on Earth (SN 1006) and just 48 years later saw the birth of the Crab Nebula (SN 1054).

Our knowledge of these events come from numerous written accounts, mainly by Chinese and Arabic astronomers (and of course from the observations we can make today of the resultant nebulae).

Now we can go one better. A team of Japanese scientists has found the first evidence of supernovae in an ice core.

The gamma rays from nearby supernova ought to have a significant impact on our atmosphere, in particular by producing an excess of nitrogen oxide. This ought to have left its mark in the Earth's ice history, so the team went looking for it in Antarctica.

The researchers took an ice core measuring 122 metres from Dome Fuji station, an inland site in Antarctica. At a depth of about 50 metres, corresponding to the 11th century, they found three nitrogen oxide spikes, two of which were 48 years apart and easily identifiable as belonging to SN 1006 and SN 1054. The cause of the third spike is not yet known.

Evil Rays

US: Thousands still lack power

Snowstorm Maine
© Jose Leiva/Sun JournalElaine Asselin of Lewiston walks her dog Zoe down Novella St. early Monday morning after the storm among the snow laden trees and power lines.

National Weather Service meteorologist Eric Schwibs says Sunday's snowstorm was the season's "highest impact event in terms of damage" because the snow was wet and heavy.

"It caused quite a bit of damage to the power grid as far as outages," Schwibs said. "I was driving home last night watching the transformers blow."

There were some impressive snowfall totals, with Livermore Falls topping out at 21 inches, Turner at 19 and Lewiston-Auburn saw 15½. Winds blowing at 35 to 40 miles per hour made the storm feel and look worse.

"This was a classic track for a snowstorm like this for us. The only real difference was the wetness and the heaviness of the snow," NWS meteorologist Jim Hayes said. "This one was more like what we'd normally see in mid to late March."

Power outages added to people's sense of frustration. Gail Rice, spokeswoman for Central Maine Power Co., said the total number of customers without power was just over 130,000 at 11 a.m. Monday; 11,000 of those customers were in the Twin Cities and surrounding area.

"The highest concentration of outages were for customers out of our Brunswick service station," Rice said.

Crystal St. Hilaire of Minot was without power from Sunday night until 2:30 p.m. Monday. She said she was equally frustrated by having no power as she was by having to clear the snow.

Igloo

US: Snowstorm cuts power to more than 140,000 in New England

Portland, Maine - More than 140,000 homes and businesses were without power Monday after a winter storm dumped wet, heavy snow on northern New England, canceling classes at hundreds of schools and creating a mess of the morning commute.

In Maine and New Hampshire, the storm arrived late Sunday and dumped heavy wet snow overnight, snapping tree limbs, utility lines and utility poles. The deepest totals were recorded in western Maine, where several towns reported getting 2 feet or more.

Maine utilities said at least 142,200 homes and businesses were without power Monday morning. About 18,500 Public Service Company of New Hampshire customers lost power, but it had been restored to all but about 3,200 homes and businesses by early morning.

Attention

Australia: Croc spotted again

crocodile
© Unknown
A four-metre crocodile seen by a fisherman near Stewart Island last week was spotted again early yesterday morning.

Environmental Protection Agency staff have warned residents to not swim in the waters near Garry's Anchorage until the crocodile is caught.

EPA spokesman Rob Allan said rangers had been patrolling the area near the south-west shore of Fraser Island since Saturday.

Mr Allan said crocodile sighting signs had been put up and EPA rangers would be placing traps in the area to try to capture the crocodile.

Fish

England: Monster of deep washes up on beach

Oar fish
© UnknownThe three metre long oarfish washed near Tynemouth Pier, North Shields
One of the rarest monsters of the deep has been washed up on a beach in North East England.

The three metre-long oarfish was found by a visitor to Tynemouth beach, in North Tyneside.

The fish is only the fourth recorded sighting of the species in the UK since 1981, but the third to be found washed up in the North East in the past seven years.

Eye 2

First pictures of endangered Saharan cheetah

Saharan cheetah
© Farid Belbachir / ZSL / OPNAThis is one of the first set of camera-trap photographs of the Saharan cheetah.

The first camera-trap photographs of the critically endangered Saharan cheetah have been taken in Algeria.

Estimates put the numbers of the animal, also known as the Northwest African cheetah (Acinonyx jubatus hecki) as low as 250, but, says Sarah Durant of the Zoological Society of London, this is guesswork. "Virtually nothing is known about the population," she says.

Durant, working with staff from the Office du Parc National de l'Ahaggar (OPNA), says the photographs were taken as part of the first systematic camera trap survey across the central Sahara, covering an area of 2,800 square kilometres.

The survey identified four different Saharan cheetahs, using spot patterns unique to each individual. The two photographs released to the media show extremely thin, hungry-looking cats.