GBOP

Effects of past climate changes

Posted: by dryan


Climate change wiped out cave bears 13 millennia earlier than thought.

Enormous cave bears, Ursus spelaeus, that once inhabited a large swathe of Europe, from Spain to the Urals, died out 27,800 years ago, around 13 millennia earlier than was previously believed, scientists have reported.

The new date coincides with a period of significant climate change, known as the Last Glacial Maximum, when a marked cooling in temperature resulted in the reduction or loss of vegetation forming the main component of the cave bears’ diet.

In a study published in Boreas, researchers suggest it was this deterioration in food supply that led to the extinction of the cave bear, one of a group of ‘megafauna’ – including woolly mammoth, woolly rhinoceros, giant deer and cave lion – to disappear during the last Ice Age.

They found no convincing evidence of human involvement in the disappearance of these bears. The team used both new data and existing records of radiocarbon dating on cave bear remains to construct their chronology for cave bear extinction.

“Our work shows that the cave bear, among the megafauna that became extinct during the Last Glacial period in Europe, was one of the earliest to disappear,” said Dr Martina Pacher of the Department of Palaeontology at the University of Vienna. “Other, later extinctions happened at different times within the last 15,000 years.”

Dr Pacher carried out the research alongside Professor Anthony J. Stuart of the Natural History Museum, London, and the University of Durham.

Many scientists previously claimed that cave bears survived until at least 15,000 years ago, but Dr Pacher and Professor Stuart claim that the methodology of these earlier studies included many errors in dating as well as confusion between cave bear and brown bear remains.

The pair also concluded, from evidence on skull anatomy, bone collagen and teeth, that these extinct mammals were predominantly vegetarian, eating a specialised diet of high-quality plants. Compared with other megafaunal species that would also become extinct, the cave bear had a relatively restricted geographical range, being confined to Europe, which may offer an explanation as to why it died out so much earlier than the rest.

“Its highly specialised mode of life, especially a diet of high-quality plants, and its restricted distribution left it vulnerable to extinction as the climate cooled and its food source diminished,” said Dr Pacher.

The brown bear, with which Ursus spelaeus shares a common ancestor, was spread throughout Europe and much of northern Asia and has survived to the present day.

“A fundamental question to be answered by future research is: why did the brown bear survive to the present day, while the cave bear did not?” said Professor Stuart. Answers to this question may involve different dietary preferences, hibernation strategies, geographical ranges, habitat preferences and perhaps predation by humans.

Cave bears were heavily built animals, with males growing up to around 1000kg. The maximum recorded weight of both Kodiak bears and polar bears – the largest bears living today – is 800kg, with averages of around 500kg.

Scientists have recovered a large quantity of cave bear remains from many cave sites, where they are believed to have died during winter hibernation. Caves provide an ideal environment for the preservation of these remains.

Despite over 200 years of scientific study – beginning in 1794 when a young anatomist, J. Rosenmüller, first described bones from the Zoolithenhöhle in Bavaria as belonging to a new extinct species, which he called cave bear – the timing and cause of its extinction remain controversial.

By far the best source of information on the appearance of cave bears in the flesh is to be found in red pigment cave paintings in the Grotte Chauvet in the Ardèche region of southern France. These are the only depictions in Palaeolithic art that can be attributed unambiguously to the cave bear.

http://en.wikipedia.org/wiki/Cave_bear

source SCIENCE, 13 OCTOBER 2006

Bear Vocalizations: What Do They Mean?

Posted: by wgardner

Being a zoo keeper I get asked a lot of questions about the animals I work with and one question that comes up a lot is: what type of vocalizations do animals make and what do they mean?

Bears have several types of vocalizations. Some species vocalize more than others. Knowing what these sounds mean can help us understand bear behavior and help with their care.

Photo of brown bear yearlings play-fighting and vocalizing in Alaska. photo credit: Chris Morgan.

Giant pandas have some unique vocalizations. They bleat which is a friendly greeting, honk when anxious or distressed and during the breeding season a receptive female will chirp when meeting a male. Sloth bears make a huffing sound when sucking up food, which sounds like a vacuum.

Most bear species make vocalizations that sound like a huff, chomp, woof, growl, and/or bark which mean the bear is agitated, angry or annoyed. A bawl, bellow, squeal or whimper indicates pain. A mumble, hum, or purr indicates contentment.

In many cases vocalizations are done along with some type of body posturing. These are visual clues as to how the bear is feeling. Depending on how the bear is standing, holding its head, the ear placement and how they move can tell a lot about what the bear is thinking and whether it is a dominant or subordinate animal. Bears would rather avoid a fight so using vocalizations and posturing can help eliminate serious conflicts and injuries and along with this, conserve energy they need to survive.

Vocalizations can be heard on the North American Bear Center’s website.

Wendy Gardner, GBOP team

Village Books in Bellingham welcomes…

Posted: by cmorgan

Join us on Wednesday, January 7th at 7pm as The Grizzly Bear Outreach Project and Village Books are proud to welcome to Bellingham David Knibb, author of Grizzly Wars: The Public Fight over the Great Bear.

Long a magnificent symbol of the wild, grizzly bears are perhaps the most controversial species in North America. In Grizzly Wars, David Knibb explores policy and political issues involved in managing and attempting to save the grizzly bear, highlighting the critical role of state governments in the recovery process, the importance of providing linked habitat areas, and our need to cooperate with Canada in managing grizzlies who inhabit border areas.

David Knibb has a background in environmental law, forestry, and wildlife management. An activist on resource conservation and environment issues in the Mountain West for nearly 45 years, he is also author of Backyard Wilderness, a chronicle of the Congressional battle over the Alpine Lakes Wilderness in Washington’s Cascades.

Chris Morgan, Director of the acclaimed Grizzly Bear Outreach Project will be at the event to share information about grizzly bears in the North Cascades. Swing by to pick up a free poster and learn about grizzlies (we may have as few as 10 of them in the Cascades!).

Bear Vision

Posted: by wgardner

Bears can see almost as well as humans, they tend to be nearsighted but have good depth perception. They have a layer of tissue called the tapetum lucidum that lies behind the retina that reflects light and improves their night vision. All bears have round pupils except giant pandas which have slits. Polar bears have a transparent eyelid (nictitating membrane) to filter snow glare and help them see underwater.

http://members.tripod.com/panowl/id27.htm

Studies have shown that bears can see colors. In a study done with giant pandas at Zoo Atlanta, it was not determined whether they could differentiate between colors but they could tell the difference between colors and gray. Being able to see colors may help bears find and distinguish ripe foods like berries, or fresh bamboo in the case of giant pandas.

For year’s people thought bears were colorblind and could not see well but research is showing this is not the case. We still have so much to learn about bears, it will be interesting to see what new things we learn in the future.

Giant Panda color vision study
Black bear and polar bear color vision study

Wendy Gardner, GBOP field specialist

Year end thank you

Posted: by cmorgan


Last month it all came flooding back to me – why I do the work that I do.

I gave a GBOP presentation to a small group of youngsters in Mount Vernon. They were all from a neighborhood that gets special attention from an amazing man – Jon Gerondale. He’s the Neighborhood Resource Officer for Mount Vernon Police in Kulshan Creek and he’s worked tirelessly to being inspiring outdoor experiences to these children. Much of his work in is collaboration with North Cascades Institute (Lee Whitford), and the US Forest Service (Don Gay). Each of these people has invested time and energy into this great group of young people.

I’d had a long, tiring day by the time I arrived at the presentation venue in Kulshan Creek, but the kids re-energized me in a big way! Thank you to you all for giving me the opportunity to bring the wonder of bears to you, and for all your great “thank you” messages! Look out for bears in 2009, and of course let us know if you come across a grizzly!

Chris Morgan
Director, GBOP

Winter Bear Idiosyncrasies

Posted: by cmorgan

Bears have some fascinating physiological traits, several of which are manifested during their winter denning period. These include: delayed implantation of the embryo for 3-4 months following the summer breeding season, and maintenance of energy and water balance during the 3-5 month denning period.

Energy and Water Balance During Winter Denning

During winter denning, which varies in length from 3-5 months, black and grizzly bears derive all of their sustenance from their own bodies. During this denning period they do not eat, drink, urinate, defecate or exercise.

Bears break down fat tissue to create water and up to 4,000 calories per day. They break down muscle and organ tissues to create protein.

Even though bears drink no water during denning, they do not become dehydrated. In a study published in the American Journal of Physiology, researchers at the Mayo Clinic found that bears were in “almost perfect water balance” after 100 days of hibernation. The metabolism of bears is of interest to researchers because a greater understanding may yield information that helps people suffering from chronic kidney failure and other health issues.

Another unique strategy is that bears are able to take urea – a primary component of urine – and use it to build new protein. Consequently bears are able use newly created protein to restore muscle and organ tissue even when they are not eating and are losing weight, something that humans most definitely cannot do!

Delayed Embryo Implantation as an Advantageous Evolutionary Feature

Delayed implantation, or embryonic diapause, is a reproductive strategy used by nearly 100 mammals including: armadillos, bats, bears, otters and badgers, seals, walrus and kangaroos. Delayed implantation results in the embryo not immediately implanting itself in the uterus following fertilization, and instead being maintained in a state of dormancy for a period of time. As a result, the normal gestation period is extended, sometimes for many months. Because delayed implantation is found in diverse species of mammals, it is likely the result of separate evolutionary processes in response to different selective pressures.

In the case of bears, it allows the female to time the delivery of cubs so that they are born during favorable environmental conditions – so that they do not arrive too early nor too late. It also protects the mother if food is scarce, as the embryo will spontaneously abort if the mother goes into the den with inadequate food stores to carry out gestation and lactation.

Bear Haiku:

Tiny twin bear cubs
Birthed into winter’s darkness
Bellies full of milk

Brown bear sleeps soundly
Winter shifts to spring’s great thaw
And life starts anew

Nan Laney, GBOP field coordinator

Has the Arctic melt passed the point of no return?

Posted: by dryan


Why are Polar Bears falling through the sea ice? Scientists have found the first unequivocal evidence that the Arctic region is warming at a faster rate than the rest of the world at least a decade before it was predicted to happen.

Climate-change researchers have found that air temperatures in the region are higher than would be normally expected during the autumn because the increased melting of the summer Arctic sea ice is accumulating heat in the ocean. The phenomenon, known as Arctic amplification, was not expected to be seen for at least another 10 or 15 years and the findings will further raise concerns that the Arctic has already passed the climatic tipping-point towards ice-free summers, beyond which it may not recover.

The Arctic is considered one of the most sensitive regions in terms of climate change and its transition to another climatic state will have a direct impact on other parts of the northern hemisphere, as well more indirect effects around the world.

Although researchers have documented a catastrophic loss of sea ice during the summer months over the past 20 years, they have not until now detected the definitive temperature signal that they could link with greenhouse-gas emissions.

However, in a study to be presented later today to the annual meeting of the American Geophysical Union in San Francisco, scientists will show that Arctic amplification has been under way for the past five years, and it will continue to intensify Arctic warming for the foreseeable future.

Computer models of the global climate have for years suggested the Arctic will warm at a faster rate than the rest of the world due to Arctic amplification but many scientists believed this effect would only become measurable in the coming decades.

The Independent

By Steve Connor, Science Editor
Tuesday, 16 December 2008

Photo credits: Peter Evins – WWF Canada, Jonathan Hayward – AP

Grizzly bears go island hopping

Posted: by dryan


Somewhere in the mist-shrouded rainforests of northern Vancouver Island, a grizzly bear is hibernating in its winter den. And he is the source of mystery, fascination, and even fear among Island residents.

As far as anyone can remember or scientists can determine, only black bears have lived on Vancouver Island.

But this year, grizzlies have been sighted far and wide on northern Vancouver Island and the knot of smaller islands that press close against the coast between Port Hardy and Campbell River.

“This year has definitely been the busiest,” Tony Hamilton, large carnivore specialist for the B.C. Ministry of Environment, said in an interview Wednesday.

“The islands are stepping stones, not separated by very much water. It makes sense. If we’re going to get grizzlies coming onto Vancouver Island, this is where they’d come through.”

Officials suspect three or four sub-adult male grizzlies are responsible for this year’s sightings, having paddled and island-hopped their way westward from the B.C. mainland.

A grizzly was photographed at Rugged Point near Kyuquot, on the northwest coast of Vancouver Island in May, close to the time bears emerge from their dens, suggesting it had successfully hibernated on the Island.

That same bear and one or more of the others sighted in the region are likely denning this winter on the Island, too.

A hunting guide spotted another grizzly near Woss later in May, followed by a sighting from a salmon farm east of Port Hardy in June. Later that month, a grizzly was shot dead at Lagoon Cove Marina on East Cracroft Island, north of Sayward.

Grizzlies are a limited-entry hunt in B.C., which means the ones on Vancouver Island are protected. Exceptions are made where the bear represents a real threat to people or property.

The next two sightings, a week apart in July, are thought to be of the same bear: first, on Malcolm Island near Sointula, then at native-owned Cluxewe Resort near Port Hardy. Conservation officers tried unsuccessfully to trap the bear.

“My advice to the ministry is that this is natural, let it happen,” said Hamilton, acknowledging some islanders are twitchy about grizzlies in their midst. “There is more sensitivity because people aren’t used to it.”

Hamilton argues it’s unlikely grizzly bears will reach a sustaining population on Vancouver Island because sub-adult males are the ones seeking out distant new territories while the younger females tend to stay closer to the home range of their birth on the mainland.

Among the theories offered for the migration of grizzlies to Vancouver Island are that the grizzly population is expanding and that bleak coastal salmon runs have forced bears to look farther afield for food. “The truth is probably somewhere in between,” Hamilton said.

Grizzlies have successfully mated with polar bears in the Arctic, but Hamilton knows of no such mating in the wild with black bears.

In 2002, a female grizzly was sighted with cubs on Hardwick Island, near Vancouver Island. The speculation is one of those cubs was shot in 2003 when it wandered into the native village of Tsulquate near Port Hardy – the first confirmed grizzly sighting on Vancouver Island.

Jeanine Johnny lives in the village and called in that bear to authorities. “They thought I was drunk, stoned,” she recalled with a laugh Wednesday. “They told me to get some sleep and that it’s just a black bear in its natural habitat.”

Johnny used to live with grizzlies in Sparwood in southeast B.C. and isn’t looking forward to their continuing presence on Vancouver Island. “It’s kind of freaky for me,” she said.

In 2006, another grizzly was shot by a man who feared for his granddaughter’s safety at Sayward. Hamilton said there were rumours of a grizzly being shot and buried – “a shoot and shovel” – in the 1970s at Sayward, but the report was never confirmed.

Reprinted from the Financial Post.

WDFW Director Resigns After 10 Years Service

Posted: by cmorgan

OLYMPIA- After a decade of leadership in fostering scientific and collaborative management of state natural resources, Washington Department of Fish and Wildlife (WDFW) Director Jeff Koenings, Ph.D., has announced his resignation, effective Dec. 11.

“In collaboration with many other resource managers and Washington citizens, I’ve accomplished much of what I said I would do when I became director 10 years ago,” Koenings said. “I’m proud of the progress we’ve made in creating a comprehensive, gravel-to-gravel system of stewardship for wild salmon, re-building relationships based on mutual trust with tribal resource co-managers, bringing a scientific focus to state fish and wildlife management and improving the department’s business practices.”

Over the past decade, WDFW has acquired more than 109,000 acres of land for the protection of fish and wildlife habitats, ensuring their place in the public lands portfolio for future generations of Washingtonians.

Koenings’ 10-year career as WDFW director was the longest in the department’s history.

“Jeff has admirably served the department and successfully navigated it through some challenging times in the last ten years,” stated Gov. Chris Gregoire. “His service is appreciated.”

As director, Koenings brought stability to the 1,500-plus employee agency, fostered partnerships with stakeholders, promoted a good-neighbor policy in managing state wildlife lands and secured millions of dollars in federal funding for state fish and wildlife management.

“The past 10 years have been extraordinary in terms of the diversity of challenges presented to WDFW and its leadership,” Koenings said. “But through it all, conservation of the resource through science-based decision-making has been our standard. I’ve been fortunate to lead an incredible group of talented professionals and they will always have my respect and admiration.”

Summarized from WDFW Release 12/1/08