Tag Archives: polar bears

Greenhouse Gas Emissions Remain the Primary Threat to Polar Bears

ANCHORAGE, Alaska — Greenhouse gas emissions remain the primary threat to the preservation of polar bear populations worldwide. This conclusion holds true under both a reduced greenhouse gas emission scenario that stabilizes climate warming and another scenario where emissions and warming continue at the current pace, according to updated U.S. Geological Survey research models.   (more…)

Read More

Scientists review the ecological effects of sea ice loss

The Arctic Ocean has more open water each summer, a trend most scientists predict will continue in coming years. September 2012 set the record for the most open water since satellite observations began.

A University of Washington researcher is co-author on a review paper published (Aug. 2) in the journal Science looking at the ecological consequences of sea ice decline.

Led by corresponding author Eric Post, a biologist at Pennsylvania State University, the international team looked at effects on animals ranging from microorganisms to polar bears. As well as obvious changes for organisms that live in or on the ice, there also are trickle-down effects for food webs, animal behavior, species ranges, interbreeding and disease dynamics. (more…)

Read More

‘House Hunters Walrus’

UD camera system records sea ice, identifies ideal walrus habitats

About the video: A University of Delaware research team led by Chandra Kambhamettu has developed a novel camera system to map the surface topography of Arctic sea ice, identifying the best “homes” for walrus.

Walrus use sea ice as a reproductive, migration and resting habitat. However, as sea ice melts and recedes, this marine mammal increasingly is threatened. (more…)

Read More

Environmental Issues: How True the Climate Changes Affecting Biodiversity

A changing climate has implications on biodiversity without any doubt. Species in the past have been sensitive to changes in the climate; that has been proved time and again by the fossilized remains and pollen distribution studies. It has been seen or can be concluded safely that climate changes have led to extinction of species in one area and colonization in another.

It is improbable that all species can or will be able to adapt to changing conditions specially the sudden changes. This leads to impact in ecosystem dynamics and also on community composition. (more…)

Read More

USGS Study Tracks Pacific Walrus, Observes Effects of Arctic Sea Ice Loss on Behavior

ANCHORAGE, Alaska — Sparse summer sea ice in the Arctic over the past five years has caused behavioral changes in Pacific walruses according to research published by U.S. Geological Survey and Russian scientists. The effects on the walrus population are unknown.

“The loss of sea ice is the ‘why’ for the change in walrus behavior; the tracking data tells us the ‘where’ in terms of their new forage patterns,” said USGS Director Marcia McNutt. “What awaits to be seen is ‘how much will it matter?'” (more…)

Read More

Projected Losses of Arctic Sea-Ice and Polar Bear Habitat may be Reduced if Greenhouse Gas Emissions are Stabilized

ANCHORAGE, Alaska – Sea-ice habitats essential to polar bears would likely respond positively should more curbs be placed on global greenhouse gas emissions, according to a new modeling study published in the journal, Nature

The study, led by the U.S. Geological Survey, included university and other federal agency scientists. The research broke new ground in the “tipping point” debate in the scientific community by providing evidence that during this century there does not seem to be a tipping point at which sea-ice loss would become irreversible.  (more…)

Read More

Biologists Report More Bad News for Polar Bears

*Climate change will force them south, where they are unsuited for the diet*

A polar bear breaks through thin Arctic Ocean ice Aug. 23, 2009. Image credit: Canadian Coast Guard/USGS

Will polar bears survive in a warmer world? UCLA life scientists present new evidence that their numbers are likely to dwindle.

As polar bears lose habitat due to global warming, these biologists say, they will be forced southward in search of alternative sources of food, where they will increasingly come into competition with grizzly bears. 

To test how this competition might unfold, the UCLA biologists constructed three-dimensional computer models of the skulls of polar bears and grizzly bears —  a subspecies of brown bears — and simulated the process of biting. The models enabled them to compare the two species in terms of how hard they can bite and how strong their skulls are.  (more…)

Read More