The Commander Islands are one of the rare places, which have two arctic foxes subspecies living in full isolation from the world around them. They differ a lot from other animals of this species. Many tens of thousands years ago Medny Island and Bering Island subspecies were separated from the rest and are very interesting to scientists. In summer 2017, soon after the arrival of the Commander Islands Reserve ornithologists group, researchers from Moscow State University and Russian Academy of Science A.N. Severtsov Institute of Ecology and Evolution came on Medny Island as a group directed by Mikhail Goldsman. The research is focused on the rare insular subspecies and conducted together in the framework of joint project with the Commander Islands Nature and Biosphere Reserve. 

The arctic fox inhabits all tundra regions of the Arctic. Because of its abilities to cover thousands of kilometers, to survive in extremely low temperatures, to endure long starvation periods and to breed fast in favorable conditions, arctic fox population in continental tundra regions of Asia, Europe and North America mix together and genetically are alike. 

Medny Island arctic fox subspecies in the hole entrance. Photo by Alexander Shiyenok 

However, the natural history and biology of the two Commander Islands populations differ from those on the continent. These insular populations are the most ancient of all insular canine populations on Earth. These animals live on small islands in total isolation for tens of thousands years. They live in uncommon for arctic foxes stable conditions and more importantly – in total dependence on the surrounding ocean. 

 “If International Union for Conservation of Nature believes the arctic fox to be an indicator of climate change, the insular forms of these animals depicts not only climate change in the water area, but also its pollution,” said Mikhail Goldsman, the head of the science team. 

The research group, headed by Mikhail Goldsman (on the right), after landing on Medny Island. Photo by members of the group 

The researchers of MSU Biology School analyze arctic foxes on Medny Island for 4 decades. Throughout the years the scientists collect information about its numbers, geographical position, family composition, nutrition, diseases, genetic changes and other key characteristics of the populations, by researching the destinies of individual animals for many generations. 

Medny Island arctic fox. Photo by Evgeny Mamaev

The possibility to see how destinies of individual insular arctic foxes develop and interact allows estimating population characteristics – survival rate, ageing processes and disease vulnerability - on a new level. 

To tell one individual from another we tag animals and renew the tags. Usually colored plastic tags are used. The animals are caught with special cages – life traps. As the name says, these devices are constructed to catch animals without harming them. However, today there is a more efficient and up-to-date technology – remote tracking with GPS, for example. Such research is very time-consuming, costly and hard to organize. 

Arctic fox on Medny Island. Photo by Alexander Shiyenok

There are about 200 longstanding projects of animals monitoring in the world. For example, chimpanzee research in Gombe Stream National Park, lion research in Serengeti and that of marmots in Colorado continue for about 60 years. 

 “The durability of a research of one population is very important,” said Mikhail Goldsman. “The most important ecological and demographic processes, which control population numbers and composition, happen through many decades and are hard to see, if you track changes for weeks, months or even several years. Telling one individual from another is a stepping stone for a number of new methodologies. If you tell one animal from another, you can understand the range of individual variation, track behavioral changes throughout its lifetime, including age related ones,” he said. 

Within its working time the group collected data on 5 to 7 generations of particular arctic fox individuals in the southern part of Medny Island. However, the goal for 2017 is even bigger – to enlarge the research for the whole territory of the island. Every bay has its own peculiarities: landscape, terrain, animals inhabiting the region and even microclimate. Life of arctic foxes in different parts of the island differs. 

Yugo-Vostochnoye marine mammals rookery. Photo by Evgeny Mamaev

The southern part of the island has big rookeries of northern fur seals and sea lions, which are absent on the North of the island. Seabirds’ colonies also vary in sizes and composition. It means, that arctic fox ration also varies. Though all sources of food for arctic foxes are of marine origin, they are contaminated with toxic chemicals in different extent. For example, the research already showed that Medny Island arctic foxes and their main food – the fulmar – have high levels of quicksilver and dioxins, which are called superecotoxicants, because they are very harmful even in small concentrations. 

With the help of GPS collars, which update geographical position of the animal every 5 minutes, it is possible to track their movements, hence their food sources. It allows acquiring data about their preferred food sources, usage of their habitats, interaction with other animals and their activities in different part of the day. 

Together with using the GPS tracking system, the researchers made a digital model, which imitates the population dynamics of arctic foxes on Medny Island. The model helps to predict any dangers for the population and to find ways to reduce the risks of extinction. The model is a part of the complex monitoring of the insular ecosystem and can become a component of our activity to assess the efficiency of nature protection activities, ecological planning, negative impacts and the possibility to compensate their influence. However the model can be used only in combination with keeping track of the actual state of the population. 

View on Medny Island. Photo by Evgeny Mamaev

Looking back, from the beginning of June 2017 a scientific group of the Commander Islands Reserve is staying on Medny Island to conduct a first in the last 25 years full ornithological research of the island. Their main goal is to make a register of seabirds’ colonies. The scientists will make thorough descriptions of colonies position and composition and will make counts of seabirds’ population numbers on Medny Island.  

Except for the team of the Commander Islands Nature and Biosphere Reserve and the collective group of MSU Institute of Ecology and Evolution, in 2017 a research group from Kamchatka filial of RAS Pacific Geography Institute Far East Division collects data on sea lions on Medny Island. We also wait for the botanists from RAS Papanin Institute for Biology of Inland Waters. 

By the way:

Medny Island is one of four islands of the Commander Archipelago. It is the second largest of them with total surface of 186 km2. The island is uninhabitable from 1970s. The only inhabited island – Bering Island – is separated from Medny by Admiral Kuznetsov Strait, which is 49 km wide and 146 m deep. The island length is 57 km, maximum width – 8.4 km (from Zhirovoy Cape to Senkinsky Cape). Medny Island is a little lower, than Bering Island. It is 360-647 m high with the highest point on Steller Mount (647 m). The shoreline of Medny Island is 164.9 km. The island was named Medny (Copper), because of native copper, which was found here nearly at the moment of the discovery of the island in the XVIII century. 

The head photo: Medny Island arctic fox. Photo by Evgeny Mamaev