"SEATTLE -- Polar bears are skating on thin ice in Alaska these days: Warming temperatures have resulted in dramatic shrinkage of sea ice, leaving the bears with fewer ice floes on which to rest and hunt seals. But at least for the moment, the Endangered Species Act won't be used to control the greenhouse gas emissions that conservationists say are contributing to climate change and posing one of the biggest threats to the bears' survival."

"A major new study has quashed fears that onshore windfarms are causing long-term damage to bird populations, but found new evidence that some species are harmed when windfarms are built."

"Scientists find that all 93 strains of bacteria collected from deep inside Lechuguilla Cave at Carlsbad Caverns in New Mexico are already resistant to at least one of the antibiotics we use to fight infections."

"Old swaths of Appalachian forest land left barren by decades of coal mining may find their past is their future, if efforts to restore the American chestnut tree in reclaimed coal fields are successful."

"CORVALLIS, Ore. -- Across the Northern Hemisphere, populations of moose, deer, and other large herbivores now far exceed their historic levels and are disrupting ecosystems, finds a new survey on the loss of large predators, particularly wolves."

"Over half of 2 million frogs imported to Bay Area annually carry disease that endangers local amphibians."

"The search for the killer of America's bees is a little bit like an Agatha Christie novel. Suspicion has turned toward one shady character and then another: declining habitat; parasites; diseases; pesticides.

Or did they all conspire in the recent mass murder of the country's bees?

This year's mild winter in much of the U.S. has meant a longer tick season. That has meant more contact between ticks and mammals like humans and dogs -- and more tick bites. It is still too early to be sure what this will mean for tick populations or the prevalence of tick-borne disease in the coming year.