Global warming threatens biodiversity

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  • #3376
    Martin W
    Participant

    Now, a thread on

    Threats to biodiversity from global warming

    In news today, an amphibian-killing disease evidently thrives with higher temperatures.

    Quote:
    A fungal disease that threatens to wipe out many amphibians is thriving because of climate change, a study suggests. Researchers studying amphibians at a national park in Spain show that rising temperatures are closely linked to outbreaks of the chytrid fungus. Chytrid fungus is a major contributor to the decline of amphibian populations around the world, threatening many species with extinction. …

    Warming link to amphibian disease A fungal disease that threatens to wipe out many amphibians is thriving because of climate change, a study suggests.

    #4362
    Martin W
    Participant

    Grim report just out from WWF; info on wwf site begins:

    Quote:
    A new report released today by WWF finds a clear and escalating pattern of climate change impacts on bird species around the world, suggesting a trend towards a major bird extinction from global warming.

    The report, Bird Species and Climate Change: The Global Status Report, reviews more than 200 scientific articles on birds in every continent to build up a global picture of climate change impacts.

    “Robust scientific evidence shows that climate change is now affecting birds’ behaviour,” said Dr Karl Mallon, Scientific Director at Climate Risk Pty. Ltd and one of the authors of the report. “We are seeing migratory birds failing to migrate, and climate change pushing increasing numbers of birds out of synchrony with key elements of their ecosystems.”

    Climate change has birds out on a limb
    (includes links to report and report summary)

    I learned of it thro Reuters report, headed “”
    Global warming could wipe out most birds: WWF

    Even back in the late 1980s, I thought there were signs that global warming was impacting bird migration on east coast of China (at and near Beidaihe); notably, some late autumn birds such as cranes were appearing later than had been noted in 1940s and earlier.
    Learned from Jesper Hornskov that changes there have continued; for instance, ice forming later as winter arrives, birds such as little egrets lingering.
    Chinese Bulbul – formerly unknown in that area – has spread there, and become a common breeding bird. Some residents apparently commoner, perhaps as result of milder winters.
    I figured that ne China maybe more prone to warming as it has rather little influence from ocean temperatures. Indeed, seems to be warming relatively fast; just found a report saying:

    Quote:
    China has been experiencing evident temperature rise in the past 50 years under global warming, with east and northeast China suffering the largest rise of 0.4 to 0.8 of a degree Celsius every ten years, said the China Council for International Cooperation on Environment and Development (CCICED).

    China’s temperature to raise 1.7 degrees Celsius by 2030

    Here in Hong Kong, a remarkably warm late autumn this year – I’m considering turning on air con just now. Surges of northerly airstreams, which help drive autumn migration, have been only feeble so far. (Perhaps not so surprising after we read of much Arctic ice melting. The masses of cold air that drive the airstreams not being chilled so much.)

    In Borneo in August, I was told of rainy season being late, but imminent; yet reports of ongoing fires show it has remained relatively dry. Yes, not unprecedented, but perhaps another worrisome sign of change. More fires, more habitats for resident birds and migrants from the north going up in smoke. (And the dry weather must make it tough for birds in the remaining forests; esp if normal behaviour might be to move, find places that may be better.)

    By contrast, another report just out telling of forest cover increasing in various places, inc China. But, this surely means plantations and secondary growth; and China reportedly sparing its own forests while involved in heavily logging others, from Siberia to PNG.

    Post edited by: Martin, at: 2006/11/14 06:02

    Post edited by: Martin, at: 2006/11/14 06:23

    #4363
    Martin W
    Participant
    Quote:
    By SETH BORENSTEIN AP SCIENCE WRITER WASHINGTON — Animal and plant species have begun dying off or changing sooner than predicted because of global warming, a review of hundreds of research studies contends. These fast-moving adaptations come as a surprise even to biologists and ecologists because they are occurring so rapidly. At least 70 species of frogs, mostly mountain-dwellers that had nowhere to go to escape the creeping heat, have gone extinct because of climate change, the analysis says. It also reports that between 100 and 200 other cold-dependent animal species, such as penguins and polar bears are in deep trouble. "We are finally seeing species going extinct," said University of Texas biologist Camille Parmesan, author of the study. "Now we’ve got the evidence. It’s here. It’s real. This is not just biologists’ intuition. It’s what’s happening." … Just five years ago biologists, though not complacent, figured the harmful biological effects of global warming were much farther down the road, said Douglas Futuyma, professor of ecology and evolution at the State University of New York in Stony Brook. "I feel as though we are staring crisis in the face," Futuyma said. "It’s not just down the road somewhere. It is just hurtling toward us. Anyone who is 10 years old right now is going to be facing a very different and frightening world by the time that they are 50 or 60."

    Study: Warming speeds species die off There’s a page of info on the Univ of Texas website, and link to pdf file of the report: Global Warming Increases Species Extinctions Worldwide, University of Texas at Austin Researcher Finds

    #4364
    Martin W
    Participant
    Quote:
    By Kim Chipman

    Dec. 27 (Bloomberg) — Global warming is causing sea ice to melt, putting polar bears at risk and prompting the Bush administration to propose listing the cold-weather mammal as a threatened species, Interior Secretary Dirk Kempthorne said.

    The loss of ice is forcing the animals inland and away from their hunting grounds. In Canada’s Western Hudson Bay, the polar bear population has declined 22 percent since 1987 and U.S. officials said they worry that similar declines may occur in Alaska.

    “There is concern their habitat may literally be melting,” Kempthorne said on a conference call with reporters.

    Polar Bears May Be Listed as Threatened by U.S. (Update1)

    #4365
    Martin W
    Participant
    Quote:
    RIO DE JANEIRO, Brazil: Global warming could spell the end of the world’s largest remaining tropical rain forest, transforming the Amazon into a grassy savanna before end of the century, researchers said Friday.

    Jose Antonio Marengo, a meteorologist with Brazil’s National Space Research Institute, said that global warming, if left unchecked, will reduce rainfall and raise temperatures substantially in the ecologically rich region.

    “We are working with two scenarios: a worst case and a second, more optimistic one,” he said in a telephone interview with The Associated Press.

    “The worst case scenario sees temperatures rise by 5 to 8 degrees (Celsius) until 2100, while rainfall will decrease between 15 and 20 percent. This setting will transform the Amazon rain forest into a savanna-like landscape,” Marengo said.

    Global warming could transform Amazon into savanna in 100 years, Brazil researchers say

    #4366
    Martin W
    Participant

    Article in Independent newspaper cites some of odd changes in wildlife as temperatures rise. This a day after I saw a near full-summer plumage Great Crested Grebe at Scarborough, North Yorkshire – till now, had seen some hundreds or thousands of these, and all those from autumn to early spring in the very different winter plumage. Also at Scarborough, a dearth of wintering sea ducks when I walked stretch of coast where I’d formerly see tens or even hundreds of them. Been here – holiday at home town – over a week now, and not even seen frost yet. Follows warmest year on record for the UK. so, from Independent:

    Quote:
    The CJ Wild Bird Foods company near Shrewsbury has announced that the demand for its products has all but disappeared, because the mild winter had maintained an alternative supply of berries for finches, tits and other species. Some species, such as the dunlin and purple sandpiper, are disappearing from Britain as they can find enough warmth in Scandinavia. … More evidence of the consequences of failure arrived yesterday from conservation groups who reported that climate change was causing the deaths of hundreds of baby hedgehogs, born out of season. Confused by the milder autumn months, the creatures are continuing to breed rather than hibernate. … An indication of the effects of climate change on fish has also arrived this week, from a team of German scientists who warned that rising sea temperatures were killing off the eelpout. The fish, which lives in the North and Baltic seas, has been hit by warmer summers, which have increased its need for oxygen at the same time as the water’s oxygen levels have dropped. The researchers’ studies of the fish’s biology showed the first thing to suffer as temperatures rise beyond 17°C was its oxygen supply. …

    ‘Irreversible’ global warming claims its first victims of the New Year – last point interesting to me, as I was recently at global warming workshop at HK Univ; aquatic life expert Prof David Dudgeon gave talk, suggesting fish [at higher altitudes, cooler places] could have problems breathing as warmer water contains less oxygen. An article on Scientific American site has more info on the fish: Fish Fin?: How Climate Change Is Hurting Cold Water Fish A bottom-loving fish in the North Sea shows how climate change can directly impact aquatic species–and presage their local doom

    Post edited by: Martin, at: 2007/01/07 18:48

    #4367
    Martin W
    Participant
    Quote:
    The Great Barrier Reef will become “functionally extinct” within decades at the current rate of global warming, while wilder weather is set to affect property values and drive up insurance bills in many Australian coastal communities.

    The Age has obtained a draft of the climate impacts report ahead of its release later this year. It includes a chapter on Australia, which warns that coral bleaching in the Barrier Reef is likely to become an annual occurrence by as early as 2030 due to warmer, more acidic seas.

    It takes at least a decade for coral to start recovering from severe bleaching. But that may not happen, with average temperatures now expected to increase by about 3 degrees this century, raising the risk that areas of coral will die outright.

    Reef ‘facing extinction’

    #4368
    Martin W
    Participant

    from the Independent:

    Quote:
    Global warming is a “weapon of mass destruction”, one of Britain and the world’s top climatologists said yesterday.

    Sir John Houghton, former director-general of the Meteorological Office and chairman of the Royal Commission on Environmental Pollution, entered the debate over the seriousness of climate change after two meteorologists were reported as saying that “some scientists have been guilty of overplaying the available evidence”. He said he agreed with the Government’s chief scientist, Professor Sir David King, that it posed a greater threat than terrorism.

    Sir John says he agrees “we must not exaggerate the evidence, and if anything must underplay it”. But he adds the evidence of serious climate change is now “very substantial”.

    Sceptics charge that the Intergovernmental Panel on Climate Change exaggerates the dangers. But Sir John, as one of the founders of the panel, says that it had “deliberately underestimated the problem”.

    Global warming is a ‘weapon of mass destruction’
    Climate experts hit back after being accused of overstating the problem

    – “weapon of mass destruction” analogy maybe a bit unfortunate after Iraq and the missing WMDs. But, warming a real problem.

    #4369
    Martin W
    Participant
    Quote:
    A warmer climate disrupts the biological clocks of migratory species including bats, dolphins, antelopes or turtles, said Lahcen el Kabiri, deputy head of the UN’s Bonn-based Convention on Migratory Species. "They are the most visible warning signs — indicators signalling the dramatic changes to our ecosystems caused in part by climate change," he told delegates on the opening day of a May 7-18 UN meeting searching for new ways to offset warming. Many creatures are mistiming their migrations, or failing to bother as changes between seasons become less clear. The shifts make them vulnerable to heatwaves, droughts or cold snaps. Among birds, for instance, cranes are starting to spend the winter in Germany rather than fly south to Spain or Portugal. "A harsh winter could decimate the population," he said. … "Climate change affects all migratory species," El Kabiri, a Moroccan, told Reuters. He said that whales were sometimes in the wrong place to feed on fish and plankton which were thriving closer to the poles because of warmer oceans.

    Migratory Birds, Whales Confused by Warming – UN

    #4370
    Martin W
    Participant
    Quote:
    From Science news (need subscription to view after a month):
    Something is harming the world’s coral reefs, and now researchers think they may have identified at least part of the problem: A devastating disease appears to attack the healthiest coral whenever sea temperatures rise. If that conclusion holds, it could force a rethinking of policies intended to protect the reefs.

    The team’s research is important because it applies an epidemiological approach to an infectious disease affecting the reef, says marine scientist Richard Aronson of the Dauphin Island Sea Lab in Alabama. That method has produced the key finding: “Temperature-mediated disease outbreaks will preferentially affect denser, healthier coral populations,” he says. Consequently, mirroring efforts to establish Marine Protected Areas, which are intended to increase fish populations, might not be the best strategy for protecting coral, Aronson says, unless it is coupled with an attempt to mitigate the effects of climate change, because encouraging denser populations in warming seas could render them more vulnerable to diseases.

    Putting the Heat on Coral

    Post edited by: Martin, at: 2007/05/23 09:34

    #4371
    Martin W
    Participant
    Quote:
    Gland, Switzerland – Whales, dolphins and porpoises are facing increasing threats from climate change, according to a new report published by WWF and the Whale and Dolphin Conservation Society (WDCS) ahead of the 59th meeting of the International Whaling Commission. The report — Whales in hot water? — highlights the growing impacts of climate change on cetaceans. They range from changes in sea temperature and the freshening of the seawater because of melting ice and increased rainfalls, to sea level rise, loss of icy polar habitats and the decline of krill populations in key areas. Krill — a tiny shrimp-like animal that is dependent on sea ice — is the main source of food for many of the great whales. … “Whales, dolphins and porpoises have some capacity to adapt to their changing environment,” said Mark Simmonds, International Director of Science at WCDS, “but the climate is now changing at such a fast pace that it is unclear to what extent whales and dolphins will be able to adjust, and we believe many populations to be very vulnerable to predicted changes.” Climate change impacts are currently greatest in the Arctic and the Antarctic. According to the report, cetaceans that rely on polar, icy waters for their habitat and food resources, such as belugas, narwhals and bowhead whales, are likely to be dramatically affected by the reduction of sea ice cover.

    Disturbed, hungry and lost – climate change impacts on whales – you can download pdf file with the report here.

    #4372
    Martin W
    Participant
    Quote:
    Plants and animals in upper Greenland have adapted their lifecycles to the arrival of the Arctic spring several weeks earlier than a decade ago.

    In a study that underscored the impact of global warming on the northern polar region, researchers discovered that plant, insect and bird life native to the High Arctic had made dramatic seasonal cycle adjustments to the region’s earlier snowmelt in the space of just 10 years.

    In some cases, flowers are emerging from buds and chicks are hatching a full 30 days sooner than they did in the mid-1990s in response to sharply increased temperatures burning off the winter’s snow layer.

    Birds such as the Sanderling and the Ruddy Turnstone had moved their springtime rituals forward by an average of two weeks by 2005, compared to 1996.

    Global warming brings early spring to Arctic

    – adaptations clearly proving possible, but will also be losers here, with some species finding conditions no longer really suit them, inc as more southerly species spread north.

    #4373
    Martin W
    Participant
    Quote:
    he State of the UK’s Birds 2006 report shows that the wintering populations of some species are declining, principally, it is suggested, because of climate change.

    The report, which examines bird population trends, has also highlighted a doubling of the overall numbers of 39 species of waterfowl spending the winter in the UK in the last three decades.

    Every winter the UK receives over five million ducks, geese, swans and wading birds, from northern Europe, Greenland, Siberia and Arctic Canada. These birds are attracted to spend the winter in Britain and Ireland because of the relatively mild climate and ice-free conditions.

    According to the State of the UK’s Birds 2006, the populations of some species, notably wading birds including the black-tailed godwit and the avocet, have increased markedly since the late 1970s. This is largely as a result of conservation action.

    However, concerns are growing over the decline in the populations of other regular visitors, including the Greenland European populations of white-fronted geese, shelduck, mallard, pochard, ringed plover, dunlin and turnstone.
    Milder winters

    The precise reasons for the decline of each species vary, but a common theme appears to be climate change. As winters become milder both in the UK and elsewhere, it appears that some birds are not flying as far as the UK to find suitable conditions: this trend has been particularly noted in Northern Ireland with declines of pochard and Bewick’s swan.

    Similar changes perhaps underway here in east Asia, too: indeed, apparent climate change effects evident at Beidaihe, east China, even by late 1980s.
    Last winter, Dalmatian Pelicans didn’t make it south as far as Hong Kong, maybe as relatively warm.

    #4374
    Martin W
    Participant

    From long article in the Independent, showing grim things are happening up north:

    Quote:
    Polar bears – the very symbol of the Arctic’s looming environmental disaster – are crashing towards extinction as a result of global warming, the US government has found. The admission, the result of a massive investigation by the Bush administration, could force the President finally to take action against climate change. The development comes at the end of the most momentous week in the human history of the Arctic, which is warming faster than anywhere else in the world. Satellite observations have revealed that its ice has shrunk to much its lowest ever level, raising fears that it had reached a "tipping point" where it would melt irreversibly, disappearing altogether in summer in less than 25 years, with incalculable global consequences, And a separate Independent on Sunday investigation has found that polar bears are being shot in alarming numbers by rich trophy hunters … The speed of the melting has taken everyone by surprise; computer models used by the Intergovernmental Panel on Climate Change predict sea ice should not retreat so far until around 2050. Traditionally the ice reaches its annual minimum in the first week of September, so it should soon start increasing again for the winter. But another record low is expected for next summer. Dr Mark Serreze of the Snow and Ice Data Centre describes the ice as being in a "death spiral… If this is not at or near a tipping point right now, then I’d hate to see what that looks like." A couple of years ago he would not have expected the Arctic to lose all its ice until the end of the century; now he expects it by 2030. This is predicted to have massive global consequences, disrupting the monsoon and bringing prolonged drought to the American midwest, which helps to feed 100 nations.

    The appalling fate of the polar bear, symbol of the Arctic

    #4375
    Martin W
    Participant
    Quote:
    Thousands of walrus have appeared on Alaska’s northwest coast in what conservationists are calling a dramatic consequence of global warming melting the Arctic sea ice. Alaska’s walrus, especially breeding females, in summer and fall are usually found on the Arctic ice pack. But the lowest summer ice cap on record put sea ice far north of the outer continental shelf, the shallow, life-rich shelf of ocean bottom in the Bering and Chukchi seas. Walrus feed on clams, snails and other bottom dwellers. Given the choice between an ice platform over water beyond their 630-foot diving range or gathering spots on shore, thousands of walrus picked Alaska’s rocky beaches. "It looks to me like animals are shifting their distribution to find prey," said Tim Ragen, executive director of the federal Marine Mammal Commission. "The big question is whether they will be able to find sufficient prey in areas where they are looking." According to the National Snow and Ice Data Center at the University of Colorado at Boulder, September sea ice was 39 percent below the long-term average from 1979 to 2000. Sea ice cover is in a downward spiral and may have passed the point of no return, with a possible ice-free Arctic Ocean by summer 2030, senior scientist Mark Serreze said. Starting in July, several thousand walrus abandoned the ice pack for gathering spots known as haulouts between Barrow and Cape Lisburne, a remote, 300-mile stretch of Alaska coastline.

    Receding Ice Displaces Alaska Walrus

    #4376
    Martin W
    Participant
    Quote:
    Around 10 per cent of the world population of Balearic shearwaters has visited UK inshore waters this summer and autumn, with more than 1,200 birds being recorded from just one watchpoint near Land’s End in Cornwall.

    The survey builds upon new research recently published in the Royal Society journal, Biology Letters, which highlights global warming as a key driver behind the upsurge in UK Balearic shearwater sightings.

    Dr Wynn and colleagues showed how northeast Atlantic sea surface temperatures rose by 0.6 degrees Celsius in the mid-1990s, triggering a northwards shift in the Balearic shearwater’s prey fish species and with it the birds that feed on them.

    ‘Just 20 years ago Balearic shearwaters were scarce visitors to South West waters, but they are now regularly recorded from headlands throughout the UK. Since 2003 we have even started seeing birds staying throughout the winter off Cornwall and the Isles of Scilly, which is a completely new phenomenon linked to elevated winter sea temperatures,’ said Dr Wynn.

    Dr Wynn added: ‘Climate change is often perceived to be a future threat, but the reality for our marine fauna is that it is happening now. Species towards the top of the food chain are having to respond very rapidly in order to survive, and some are going to be pushed to extinction if they fail’.

    Climate Change Drives Endangered Seabird Into UK Waters

    #4377
    Martin W
    Participant

    Not so obviously a species in peril, but further signs of change seen in New England, US, now witnessing later, duller autumn tree colours. Tourism to perhaps suffer; but also mention re fungus able to attack more.

    Quote:
    Forested hillsides usually riotous with reds, oranges and yellows have shown their colors only grudgingly in recent years, with many trees going straight from the dull green of late summer to the rust-brown of late fall with barely a stop at a brighter hue. "It’s nothing like it used to be," said University of Vermont plant biologist Tom Vogelmann, a Vermont native. He says autumn has become too warm to elicit New England’s richest colors. According to the National Weather Service, temperatures in Burlington have run above the 30-year averages in every September and October for the past four years, save for October 2004, when they were 0.2 degrees below average. … warmer autumns and winters have been friendly to fungi that attack some trees, particularly the red and sugar maples that provide the most dazzling colors. "The leaves fall off without ever becoming orange or yellow or red. They just go from green to brown," said Barry Rock, a forestry professor at the University of New Hampshire.

    Climate Change Blamed for Fading Foliage

    #4378
    Martin W
    Participant

    From the Guardian:

    Quote:
    Rising global temperatures caused by climate change could trigger a huge extinction of plants and animals, according to a study. Though humans would probably survive such an event, half of the world’s species could be wiped out.

    Scientists at the University of York and the University of Leeds examined the relationship between climate and biodiversity over the past 520m years – almost the entire fossil record – and uncovered an association between the two for the first time. When the Earth’s temperatures are in a “greenhouse” climate phase, they found that extinctions rates were relatively high. Conversely, during cooler “icehouse” conditions, biodiversity increased.

    The results, published today in the Proceedings of the Royal Society B, suggest that the predictions of a rapid rise in the Earth’s temperature due to man-made climate change could have a similar effect on biodiversity.

    Peter Mayhew, a population ecologist at the University of York and one of the authors of the research paper, said: “Our results provide the first clear evidence that global climate may explain substantial variation in the fossil record in a simple and consistent manner. If our results hold for current warming – the magnitude of which is comparable with the long-term fluctuations in Earth climate – they suggest that extinctions will increase.”

    Warming could wipe out half of all species

    #4379
    Martin W
    Participant

    From Associated Press:

    Quote:
    More than 3,000 flying foxes dropped dead, falling from trees in Australia. Giant squid migrated north to commercial fishing grounds off California, gobbling anchovy and hake. Butterflies have gone extinct in the Alps. While humans debate at U.N. climate change talks in Bali, global warming is already wreaking havoc with nature. Most plants and animals are affected, and the change is occurring too quickly for them to evolve. "A hell of a lot of species are in big trouble," said Stephen E. Williams, the director of the Centre for Tropical Biodiversity & Climate Change at James Cook University in Australia. "I don’t think there is any doubt we will see a lot of (extinctions)," he said. "But even before a species goes extinct, there are a lot of impacts. Most of the species here in the wet tropics would be reduced to … 15 percent of their current habitat." … With warmer weather, 60 percent of plant and animal species are migrating, breeding and blooming earlier in the spring, Parmesan said. But not all are, and that could upset relationships between birds and the insects they feed on as well as insects and the flowers they pollinate.

    Global Warming Wreaks Havoc With Nature

    #4380
    Martin W
    Participant

    From The Times:

    Quote:
    The Emperor penguins which won the hearts of millions of children in the film Happy Feet have suffered a devastating population slump in the last 50 years, according to a report.

    Many colonies have fallen in size by 50 per cent as the penguins have been squeezed by the effects of climate change and overfishing, the WWF said in its report, Antarctic Penguins and Climate Change.

    Sea ice on the western peninsula of Antarctic has retreated 40 per cent in the last three decades and is thought to be partly to blame for huge falls in the stocks of krill, a shrimp-like creature eaten by the penguins. Another factor is overfishing by humans.

    The quantities of krill, which live under the ice where they feed on microscopic plant life, are estimated to have fallen 80 per cent in the last decade alone in part of the conbtinent’s western peninsula.

    Warming in the Antarctic western peninsula is taking place about five times faster than other parts of the planet.

    Nesting sites are destroyed by the the melting ice and the emperor penguins have suffered more thyan any other species in Antarctica.

    Gentoos and chinstraps are being forced further south by the warming temperatures and this is putting extra pressure on the emperors and Adelie species.

    Penguins in decline due to global warming

    #4381
    Martin W
    Participant

    Polar Bears International website has good info countering claims that polar bear populations are increasing so no worries for them with global warming.

    Quote:
    Dr. Derocher is a polar bear scientist with the University of Edmonton in Canada. He also serves on PBI’s Scientific Advisory Council.

    The various presentations of biased reporting ignore, or are ignorant of, the different reasons for changes in populations. If I thought that there were more bears now than 50 years ago and a reasonable basis to assume this would not change, then no worries. This is not the case.

    The bottom line here is that it is an apples and oranges issue. The early estimates of polar bear abundance are a guess. There is no data at all for the 1950-60s. Nothing but guesses. We are sure the populations were being negatively affected by excess harvest (e.g., aircraft hunting, ship hunting,self-killing guns, traps, and no harvest limits). The harvest levels were huge and growing. The resulting low numbers of bears were due only to excess harvest but, again, it was simply a guess as to the number of bears.

    After the signing of the International Agreement on Polar Bears in the 1970s, harvests were controlled and the numbers increased.

    There is, however, very strong evidence for a decline in Western Hudson Bay and the Southern Beaufort Sea based on quantitative studies. More recently, scientists working in the Southern Hudson Bay have reported a major decline in the condition of polar bears. A decline in condition was the precursor to the population decline in Western Hudson Bay. There is clear suggestion of a population decline due to over-harvest in Baffin Bay, Kane Basin and possibly Norwegian Bay.

    Look at the messengers: lobby groups for big business say there is no problem.

    Comparing declines caused by harvest followed by recovery from harvest controls to declines from loss of habitat and climate warming are apples and oranges. Ignorant people write ignorant things.

    Ask the Experts: Are Polar Bear Populations Increasing?

    #4382
    Martin W
    Participant

    Following on from above post, comes this news on National Geographic website:

    Quote:
    King penguins near the Antarctic may be on a perilous path to extinction as a result of global warming, new research suggests.

    Populations of the large birds on Possession Island in the Indian Ocean’s Crozet Archipelago are declining as sea temperatures warm and the birds are forced to travel longer distances to find food.

    In recent years, many of the prey species have died or migrated as the ocean warms and the algae that those animals eat are impacted.

    Warming temperatures also force fish to swim into cool waters farther away from the island, causing penguins to travel greater distances to hunt. The longer time away from home reduces chick feedings, the researchers found.

    So during years when seas become warmer, penguins do not breed as successfully, Le Maho and colleagues found.

    At the edge of the sea ice, where penguin adults forage during winter, just a 0.47 degree Fahrenheit (0.26 degree Celsius) increase resulted in a 9 percent decrease in the population two years later.

    King Penguins Declining Due to Global Warming

    #4383
    Martin W
    Participant

    further threats to Antarctic biodiversity:

    Quote:
    Unique marine life in Antarctica will be at risk from an invasion of sharks, crabs and other predators if global warming continues, scientists warn.

    Crabs are poised to return to the Antarctic shallows, threatening creatures such as giant sea spiders and floppy ribbon worms, says a UK-US team.

    Some have evolved without predators for tens of millions of years.

    Bony fish and sharks would move in if waters warm further, threatening species with extinction, they say.

    In the last 50 years, sea surface temperatures around Antarctica have risen by 1 to 2C, which is more than twice the global average.

    Warming risks Antarctic sea life

    #4384
    Martin W
    Participant
    Quote:
    Fewer caribou calves are being born and more of them are dying in West Greenland as a result of a warming climate, according to Eric Post, a Penn State associate professor of biology. Post, who believes that caribou may serve as an indicator species for climate changes including global warming, based his conclusions on data showing that the timing of peak food availability no longer corresponds to the timing of caribou births.

    caribou are unable to keep pace with certain changes that have occurred as a result of global warming. When the animals arrive at their calving grounds now, pregnant females find that the plants on which they depend already have reached peak productivity and have begun to decline in nutritional value. According to Post, the plants — which initiate growth in response to temperature, not day length — are peaking dramatically earlier in response to rising temperatures. “Spring temperatures at our study site in West Greenland have risen by more than 4 degrees Celsius over the past few years,” said Post. “As a result, the timing of plant growth has advanced, but calving has not.”

    Global Warming Linked To Caribou-calf Mortality

    #4525

    from National Geographic:

    Quote:
    This January—deep summer in Antarctica—explorer Jon Bowermaster suffered through a five-day stretch of torrential rains on the west side of the Antarctic Peninsula. The same cannot be said for thousands of downy penguin chicks. Epic rains are unusual in Antarctica, even in summer, said Bowermaster, who had been in the region on an expedition funded in part by the National Geographic Society’s Expeditions Council. With daytime temperatures above freezing, the rains soaked young Adélie and gentoo penguins not yet equipped with water-repellent feathers (see video below). At night, when the mercury dipped below freezing, the wet chicks froze. … Increasing temperatures are also affecting breeding populations in Antarctica by breaking up ice, changing precipitation patterns, and altering nesting times, Boersma writes.

    Penguin Chicks Frozen by Global Warming?

    #4533

    AFP item includes:

    Quote:
    The habitats of wild bird species are shifting in response to global warming, but not fast enough to keep pace with rising temperatures, according to a study released Wednesday.

    Researchers in France also found that the delicate balance of wildlife in different ecosystems is changing up to eight times more quickly than previously suspected, with potentially severe consequences for some species.

    "The flora and fauna around us are shifting over time due to climate change," said lead author Victor Devictor, a researcher at the French National Museum of Natural History.

    "The result is desynchronisation. If birds and the insects upon which they depend do not react in the same way, we are headed for an upheaval in the interaction between species," he explained in a telephone interview.

    These "mismatches" are likely to become greater over time, and could eventually threaten some birds with extinction, he added.

    The study showed that the geographic range of 105 birds species in France — accounting for 99.5 percent of the country’s wild avian population — moved north, on average, 91 kilometres (56.5 miles) from 1989 through 2006.

    Average temperatures, however, shifted northward 273 kilometres (170 miles) over the same period, nearly three times farther.

    Birds can’t keep up with climate change: study

    #4556

    From National Geographic:

    Quote:
    Climate change may be responsible for shrinking lemming populations in Norway, a new study shows. As a result, the lack of the small mammals is cascading through the ecosystem, forcing predators to find different food sources.

    In recent years, warmer temperatures have been changing the structure of the snow—with devastating effects for the lemmings.

    Rather than remaining below freezing for most of the winter, temperatures have bounced above freezing a number of times, melting and then refreezing the snowpack.

    "This enables water to enter the system, flooding the snow tunnels and then forming ice layers on the ground," Kausrud said.

    Many lemmings drown when their burrows are flooded, and those that survive often starve when their food is trapped under an icy layer.

    Unable to gorge themselves on lemmings every few years, predators like the Arctic fox and snowy owl have had to rely on other food sources, such as ptarmigan (a kind of grouse) and willow grouse.

    As a result, the numbers of these ground-nesting birds have been diminishing. "Lemming population explosions help to take the pressure off ptarmigan and willow grouse," Coulson explained.

    Although the study looks only at one region in Norway, Kausrud and his colleagues believe the effect could be widespread.

    Global Warming Threatens Lemmings in Norway

     

    #4560

    From Sydney Morning Herald:

    Quote:

    VAST numbers of marine "jelly balls" now appearing off the Australian east coast could be part of the planet’s mechanism for combating global warming.

    The jellyfish-like animals are known as salps and their main food is phytoplankton (marine algae) which absorbs the greenhouse gas carbon dioxide in the top level of the ocean. This in turn comes from the atmosphere.

    Dr Baird was part of a CSIRO and University of NSW marine survey last month that found a massive abundance of salps in the waters around Sydney. They were up to 10 times what they were when first surveyed 70 years ago.

    Different salp species are found around the world and attention is now being paid to what effect they might have on global warming.



    ‘Jelly balls’ may slow global warming

     

     

    #4576

    Evidence that moose numbers falling on southern edge of their range:

    Quote:
    It wasn’t long ago that thousands of moose roamed the gentle terrain of northwestern Minnesota, affirming the iconic status of the antlered, bony-kneed beast from the North Woods. In just two decades, though, their numbers have plummeted, from 4,000 to fewer than a hundred.

    They didn’t move away. They just died.

    The primary culprit in what is known as the moose mystery, scientists say, is climate change, which has systematically reduced the Midwest’s already dwindling moose population and provoked alarm in Minnesota, where wildlife specialists gathered for a "moose summit" last month in Duluth.

    "There’s not a lot of opportunity to turn this around," said Mark Lenarz, a wildlife research specialist at the Minnesota Department of Natural Resources. "Here in Minnesota, they (moose) have been weakened by climate change."

    Temperatures tell much of the story. Over the past 40 years in northwest Minnesota, the average winter temperature has risen significantly — 12 degrees — while summers are 4 degrees warmer. Solitary and temperamentally grumpy, moose have made it clear in their estimated 13,000 years in North America that they hate warm weather.

    Iconic moose may lose battle with climate change

    The beasts are dying off in the Midwest, failing to adapt to warmer temperatures

     

    #4583

    From Christian Science Monitor:

    Quote:
    Old-growth forests in the Western United States appear to be losing ground to the regional effects of global warming.

    That’s the conclusion a team of federal and university-based forest ecologists have reached after looking at long-term trends in patches of relatively pristine old-growth forests.

    After examining a range of possible causes for the region-wide pattern, the last ones standing are the West’s warming trend and warming’s effect on the amount of water these areas receive. Summer dry spells are longer. Snows melt earlier. More winter precipitation falls as rain, rather than snow, and the snow that falls has a lower water content than it once did.

    The study adds to a growing body of research that suggests any country with extensive forests – whether tropical, temperate, or boreal – may deserve a place at the table when global climate talks discuss “avoided deforestation” as a tool for reducing greenhouse-gas emissions.

    US forests hold new evidence of global warming

     

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