Earth ChangesS


Appetite for frogs' legs harming wild populations

frog legs
© Andrew McConnell/Robert Harding Picture Library Ltd/AlamyGastronomic demand may be depleting regional populations of many frogs to the point of no return.

Are frogs being eaten to extinction? We're used to hearing about how disease, climate change, and habitat degradation are endangering amphibians, but conservationists are warning that frogs could be going the same way as the cod. Gastronomic demand, they report, is depleting regional populations to the point of no return.

David Bickford of the National University of Singapore and colleagues have called for more regulation and monitoring in the global frog meat market in order to avoid species being "eaten to extinction".

Statistics on imports and exports of frog legs are sparse as few countries keep track of the amount of meat harvested and consumed domestically.

According to UN figures, global trade has increased in the past 20 years. France - not surprisingly - and the US are the two largest importers; with France importing between 2500 and 4000 tonnes of frog meat each year since 1995.


Sex Smell Lures 'Vampire' To Doom

Vampire Fish
© Gary MaszarosThe sea lamprey's mouth has garnered it the nickname "vampire fish."
A synthetic "chemical sex smell" could help rid North America's Great Lakes of a devastating pest, scientists say.

US researchers deployed a laboratory version of a male sea lamprey pheromone to trick ovulating females into swimming upstream into traps.

The sea lamprey, sometimes dubbed the "vampire fish", has parasitised native species of the Great Lakes since its accidental introduction in the 1800s.

The work is reported in Proceedings of the National Academy of Sciences.

The Great Lakes on the US-Canada border support recreational fishing worth billions of dollars a year, which the lampreys would wreck but for a control programme costing about ยฃ20m annually.

This is thought to be the first time that pheromones have been shown to be the basis of a possible way of controlling animal pests other than insects.

Better Earth

New Ice Age Maps Point to Climate Change Patterns

Ice Age Map
© Dr Timothy Barrows/ElsevierNew Ice Age maps point to climate change patterns.
New climate maps of the Earth's surface during the height of the last Ice Age support predictions that northern Australia will become wetter and southern Australia drier due to climate change.

An international consortium of scientists from 11 countries has produced the maps, which appear in this week's issue of Nature Geoscience.

Dr Timothy Barrows of the Research School of Earth Sciences at The Australian National University was responsible for the Australian sector of the reconstruction.

"During the last Ice Age - around 20,000 years ago - sea surface temperature was as much as 10 degrees colder than present and icebergs would have been regular visitors to the southern coastline of Australia," Dr Barrows said.

The temperature was estimated by measuring changes in abundance of tiny plankton fossils preserved on the sea floor, together with chemical analyses of the sediment itself.

Bizarro Earth

Flashback GM damages environment but not pests, says study

Scientists were yesterday embroiled in an international row over genetically modified cotton after a study in China suggested for the first time that the crop was permanently damaging the environment and that insects were building up resistance to it.

The study by the Nanjing institute of environmental sciences, part of the Chinese government's environmental protection administration, draws together laboratory and field work undertaken by four scientific institutions in China over several years.

It suggests that GM cotton, which incorporates a gene isolated from the bacterium Bacillus thuringiensis (Bt), harms the natural parasitic enemies of the cotton bollworm, the pest that it is designed to control. It also indicates that populations of pests other than cotton bollworm had increased in Bt cotton fields and some had replaced it as primary pests.


Costa Rica calls off search for earthquake victims

San Jose - Costa Rican authorities called off their search on Monday for victims of landslides from an deadly earthquake 11 days ago.

Rescue teams have pulled 23 bodies from the Poas volcano region, where waves of earth buried cars and crushed homes during a 6.1 magnitude quake on Jan 8. Seven people are still missing, officials said.


Carnivorous sea squirt: Venus fly trap of deep

sea squirt
© AFP/CSIRONew to science: The carnivorous sea squirt springs shut on unsuspecting prey much like a venus fly trap, say researchers.

Biologists have uncovered new marine animals in a search of previously unexplored Australian waters, including a bizarre carnivorous sea squirt and ocean-dwelling spiders.

A joint U.S.-Australian team spent a month in deep waters off the coast of the southern island of Tasmania to "search for life deeper than any previous voyage in Australian waters," said lead scientist Ron Thresher with Australian government research agency the CSIRO's Marine and Atmospheric division.


Army worms decimate crops in north-central Liberia

Monrovia - Swarms of army worms have attacked crops in a food-producing district of Liberia, forcing the West African state to declare a state of emergency in the area at the weekend, the Ministry of Agriculture said on Monday.

Army worms, which can grow to around 5 centimetres (two inches) in length, are moth caterpillars and when present in large numbers can destroy swathes of vegetation and crops.

"We are calling for international assistance to combat these insects. They have affected over 19 villages in Bong county," Agriculture Minister Christopher Toe told Reuters.

Cloud Lightning

Less Fog Explains Warming Europe, Study Says

Fewer foggy, misty and hazy days help explain why Europe's temperatures have risen so fast over the past 30 years, a finding that could help predict future climate change, researchers said on Sunday.

Clearer skies due to changing weather patterns and less air pollution have contributed on average to about 5 to 10 percent of the region's warmer temperatures during this period, said Geert Jan van Oldenborgh, a researcher at the Royal Netherlands Meteorological Institute.

"The temperatures in Europe have been going up twice as fast as climate models had predicted in the past decades. Less fog means more sunshine on the ground and hence higher temperatures," Van Oldenborgh, who worked on the study said in a telephone interview.


US: Mystery of sick pelicans still puzzling experts

Los Angeles - A mysterious illness afflicting California brown pelicans continues to take its toll.

The Northern California-based International Bird Rescue Research Center said Thursday it had counted 460 sick or dead birds so far, up from 265 last week. The birds were found along the West Coast from Baja California in Mexico to Oregon.

Better Earth

Japan: Nine-limbed octopus gives aquarium a leg up

Nine-arm octopus
© Mainichi (file photo)The nine-armed octopus is pictured in Susami, Wakayama Prefecture in this Dec. 25, 2008
Susami, An octopus found off the coast of Susami is attracting attention for an unusual reason -- its nine arms.

The blue-ringed octopus, found by a researcher from the Susami Crustacean Aquarium, is on display.

"Octopus arms grow back if they are cut off, and it's possible that the ninth arm grew out of a wound or from some other stimulus," said aquarium head Takuya Mori.