Arctic predators and climate change

“It appears that the good years for lemmings are becoming rarer with global warming,” says Professor Ims, adding. “This can result in the Arctic fox and snowy owl, two of the most characteristic species in the Arctic, disappearing from the tundra.”

“As a result of a warmer climate, the living conditions of the Arctic fox’s toughest competitor, the red fox, will improve markedly.

“Professor Yoccoz says other Arctic specialties among predators such as the long-tailed skua and the snowy owl can disappear and be replaced by species including the golden eagle.”

innovations-report 24.05.2007
URL:
http://www.innovations-report.de/html/berichte/umwelt_naturschutz/bericht-84808.html
24.05.2007

As part of the International Polar Year (IPY), four projects from the University of Tromsí¸ have received funding from the Research Council of Norway (NFR) to start research which can contribute to a wider understanding of climate change in the Arctic.

One of these project concerns the reduction in the population of several Arctic predators, including the Arctic fox, which is now classified as an endangered species.

The project is headed by Professor Nigel Yoccoz in collaboration with Professor Rolf Anker Ims. They are interested in the full effects of climate change on the Arctic ecosystems.

“We will collaborate with several researchers from the Norwegian Polar Institute and the University of Moscow,” says Professor Yoccoz. “This project has funding of NOK 9 million, which enables collaboration with Russian PhD students.”

Predators reflect the ecological balance

Professors Yoccoz and Ims say that the Arctic fox’s habitat in the Arctic tundra is in a hairline balance in an ecosystem which is vulnerable to climate change. As such, the Arctic fox and other similar predators can be used as indicators of what is occurring in the system as a whole.

“Research on ecosystems is complex as it deals with dynamics in all living species in interaction with each other and with non-living aspects of their environment,” says Professor Ims. “One of the objectives of this project is to examine whether it’s possible to create a simplification by using the predator community as an ecosystem indicator.”

Species at the top of the food chain in the tundra are predators such as the Arctic fox, snowy owl, rough-legged buzzard and three species of Arctic skua. Changes in food chain are most visible among these species because small changes in the prey population can cause reproduction of predators to fail completely.

The Arctic fox as a key species

“The Arctic fox is being utilised as the key species in this research project because it is found through the tundra area, as well as being in clear decline in many areas,” says Professor Ims. “The Arctic fox population is on the decline in particular in the southern part of the tundra and in the Scandinavian high mountains. It is in danger of disappearing from Norway.”

Professor Yoccoz adds: “We will carry out field work from Svalbard in the north via the Varanger Peninsula in East Finnmark in Norway to several places in Northern Russia. We will look at the geographical variations in the predator population and compare our findings with those in an equivalent research project in Canada and other parts of North America, which we are co-ordinated with through IPY.”

Researchers at UiT already know a lot about the Arctic fox. The researchers are also involved in a conservation project to protect the Arctic fox in Finnmark. At the turn of the last century, there were thousands of Arctic foxes in Norwegian mountain and northern coastal areas. The population has now been decimated to just 100.

Reliant on a good lemming year

“We know that the Arctic fox and many other tundra predators completely stop breeding in the years when there are few lemmings,” says Professor Yoccoz. “We also know that in a good lemming year as many as 16 Arctic fox cubs can be born into a litter. This means that the species can continue even though it does not reproduce for three to five years. However, if the good lemming years are few and far between, it could be catastrophic for the Arctic fox.”

The Norway lemming is a key species in the Arctic tundra, and it can have a significant effect on the entire food chain from vegetation to predators. It will take a long time to observe how the vegetation reacts to a reduction in lemming numbers. However, the predators react quickly to a food shortage.

“It appears that the good years for lemmings are becoming rarer with global warming,” says Professor Ims, adding. “This can result in the Arctic fox and snowy owl, two of the most characteristic species in the Arctic, disappearing from the tundra.”

Researchers want better collaboration with Russia

An important aspect of this Norwegian IPY project is to improve the ecological research collaboration with Russia.

“There is little in the way of collaboration in environmental research between Norway and Russia which concerns the tundra, despite the fact that Russia manages an extremely large part of this ecosystem,” says Professor Ims. “There are probably political and economical reasons why this field has until now had a lower priority.”

Tundra consumed by forest

The researchers believe it is important for the IPY to create possibilities for ecological approaches to climatic problems because, if the changes to our climate are great, there will be a tragedy in the Arctic in the form of a loss of the unique biological diversity.

“Rapid climate change can result in the world losing its biodiversity,” says Professor Ims. “The Arctic tundra can be particularly vulnerable. There is a relatively narrow strip between the northern forest and the Arctic sea areas. If the scenarios for climate change are correct, the forest can in time stretch right out to the coast and completely consume this unique ecosystem.”

As a result of a warmer climate, the living conditions of the Arctic fox’s toughest competitor, the red fox, will improve markedly.

Professor Yoccoz says other Arctic specialties among predators such as the long-tailed skua and the snowy owl can disappear and be replaced by species including the golden eagle.

“The IPY should leave a legacy, which researchers and the conservation authorities must follow up,” says Professor Ims, concluding: “IPY lasts far too short a time to completely solve the problem, but we hope to be able to start things which will increase our level of activity. Our binding collaboration with the Russians shall at any rate be pursued.”

Karen Marie Christensen | Quelle: alphagalileo Weitere Informationen: www.uit.no

—————————————————
“… the Oakland and San Francisco airports could be under water by 2100 if seawalls aren’t erected to protect them from the already rising sea, scientists warn. And some bird and fish species could become extinct as ecological changes affect their local habitat.”

” … for large swatches of real estate – primarily areas built on landfill – the end result could be devastating. ‘It will absolutely flood lots of homes and businesses.'”

Global warming enlarging San Francisco Bay, scientists say
By Julie Sevrens Lyons
Mercury News
San Jose Mercury News
Article Launched:05/24/2007 02:22:47 AM PDT

In one of the most detailed looks at global warming’s impact on the Bay Area, scientists Wednesday painted a grim portrait of increasing heat waves, droughts, water shortages and wildfires accompanied by more severe thunderstorms, flooding and coastal erosion.

Low-lying areas such as Alviso and the Oakland and San Francisco airports could be under water by 2100 if seawalls aren’t erected to protect them from the already rising sea, scientists warn. And some bird and fish species could become extinct as ecological changes affect their local habitat.

“This is not fantasy,” said David Reynolds, a meteorologist with the National Weather Service. “These sorts of things are already occurring.”

Scientists gathered in San Francisco for the workshop on California climate change, which was sponsored by the National Oceanic and Atmospheric Administration.

While many Americans have long equated global warming with changes to glaciers and ice caps in the Antarctic, the scientists stressed that climate change is coming to our own backyards.

In fact, said Will Travis, executive director of the San Francisco Bay Conservation and Development Commission, “it’s already here.”

The severity of global warming has not been consistent around the globe, according to researchers. In this country, for example, the westernmost states have been – and will continue to feel – the effects the most.

“The problem of climate change is local. It will have a tremendous impact on San Francisco Bay,” Travis said. And the need for major solutions to slow the warming trend is even more urgent here than in other parts of the country because there’s so much development close to the bay, Travis said.

Sea level rising

One of the most striking examples of climate change can already be seen in the bay, where, because of global warming, the sea level is already seven inches higher than it was little more than a century ago. Scientists expect that, if greenhouse gases are not kept in check and global temperatures continue to rise, the bay could rise an additional 1 to 3 feet by 2100.

“The bay is going to get bigger,” Travis said. And for large swatches of real estate – primarily areas built on landfill – the end result could be devastating. “It will absolutely flood lots of homes and businesses.”

Before the Gold Rush, the bay used to be much larger, measuring about 787 square miles, Travis said. The addition of landfill along the bay’s edges has reduced its size to about 548 square miles. But rising sea levels could bring the bay back to its original size, wiping out myriad housing developments and business parks in the process.

Scientists are also seeing climate change influence the region in many other ways. Global warming isn’t just making the area warmer – with a 1 degree average air temperature rise in the past century – it is subjecting us to more extreme weather.

Evidence points to an increase in heavy rainstorms in California, Reynolds said. Coastal flooding and erosion are also more prevalent because of the stronger storms and rise in sea levels. And while daytime temperatures are largely the same, there has been a significant increase in overnight temperatures.

The “San Jose heat storm of 2006,” as Reynolds called it, may have baked the Bay Area in 100-degree-plus temperatures, but it alarmed scientists because “the hills did not fall below 90 degrees at night.”

Said Reynolds: “It’s sobering. These are real numbers from climate stations in the Bay Area that have shown these temperature rises.”

Oceanographers are also lamenting climate-induced ecological changes which, they say, could reduce or displace fisheries, affect the reproduction and migration of sea life, and reduce coastal water quality.

Warm-water animals

Global warming is occurring to the detriment of salmon, squid and anchovies, although there are some winners, like exotic fish.

“The environment is becoming more favorable to animals that like warmer water,” said Frank
Schwing, an oceanographer with NOAA’s National Marine Fisheries Service.

While many species are resilient and can bounce back from changes in their environment, the acceleration of global warming “is not giving wildlife the opportunity to adapt in the way it normally would,” said Maria Brown, superintendent of the Gulf of the Farallones National Marine Sanctuary in San Francisco.

Warmer, less nutritious water is rising up in the bay, which is affecting the health and reproduction of some local sea life, Brown said.

Cassin’s auklets, birds which nest on the Farallon Islands and along Año Nuevo, have failed to breed in the region for two years – something that’s unprecedented in the history of that species on the islands, Brown said.

In addition, he said, blue whales have also temporarily abandoned their feeding grounds in the area because of a lack of prey – primarily the absence of tiny crustaceans called krill that are at the heart of the aquatic food chain.

Contact Julie Sevrens Lyons at jlyons@mercurynews.com or (408) 920-5989.

Bookmark the permalink.

Comments are closed