How Will Climate Change Affect Arctic Predators?

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.”