As the climate around the world changes a new study in PlosOne has demonstrated that most mammal species in the Arctic and subArctic regions will benefit as the environment changes – if they get passage to the new habitats. Only the highly specialised cold region mammal species are likely to be threatened – but the modelling indicates that no species will go extinct.
The study undertaken by Umeå University, Sweden also highlights the potential of increased competition between species as new lower latitude predators move northwards to compete with their cold environment cousins.
We also provide evidence that for most (sub)arctic mammals it is not climate change per se that will threaten them, but possible constraints on their dispersal ability and changes in community composition.
The scientists Anouschka Hof, Roland Jansson, and Christer Nilsson of the Department of Ecology and Environmental Science at Umeå University investigated how future climate changes may come to impact mammals in northern Europe’s Arctic and sub-Arctic land areas, Their study excluded the Arctic seas and islands.
Using mathematical model of expected changes to the habitat and environment of the European Arctic region they were able to determine that most mammal species in the region would benefit from the changes expected to occurr to 2080. Examples of cold environment species that will not benefit were lemmings and the arctic fox.
The one major obstacle that will prevent wildlife from benefiting from the changes to the Arctic will be if the species were not able to expand out into the newly released habitat. This could happen if there are not sufficient wildlife friendly corridors to connect up fragmented habitats.
Christer Nilsson, professor of landscape ecology, speaking about the potential benefits to wildlife explained, “This will be the case only on the condition that the species can reach the areas that take on the climate these animals are adapted to. We maintain that it is highly improbable that all mammals will be able to do so, owing partly to the increased fragmentation of their living environments caused by human beings. Such species will reduce the extent of their distribution instead,”.
Changes to species mix could also impact on species numbers and whether they are able to adapt. As new mammals move northward they will come into contact and predate on species who have not experienced the new species before. There could also be clashed as new species try to move into niches that are already occupied by other species.
One of the conclusions that the researcher make is that if climate change in the Arctic continues as predicted there should not be any extinctions but if climate change in the Arctic is greater than predicted then there could be loss of species.
The models showed that of 61 species studied 43 of the species will benefit and expand their range. The expansion of their range would generally be in a north-easterly direction as they colonise land that becomes climatically suitable for them.
They predict that in the European sub Arctic region 10 new mammal species will appear in the region – 8 of which will be bats that will see big expansions in their range.
Eight species are expected to see a reduction in range due to loss of suitable habitat, Three of these species are already in decline – the wolverine (Gulo gulo), the grey red-backed vole (Myodes rufocanus), and the Siberian flying squirrel.
The impact of changing species mix is demonstrated by the potential increase in predator numbers on the tundra vole. At present the climate means only 1% of vole habitat is able to support three or more predator species. By 2080 39% of the voles range will be climatically favourable to three or more predator species.
They concluded that, “We also provide evidence that for most (sub)arctic mammals it is not climate change per se that will threaten them, but possible constraints on their dispersal ability and changes in community composition.”