A study carried out by researchers at the University of Exeter using twenty-two years of data on American squirrels in Yukon, Canada, found that when red squirrels live beside “familiar neighbours” it “boosts a squirrel’s chances of survival and successful breeding”. The American red squirrel is a different species to the one found in Britain.
Inherently, red squirrels are solitary and they defend their territory at the centre of which is a food stash called a “midden”. This leads scientists into believing that they are highly competitive and don’t cooperate with their neighbours.
However, the researchers found that they do become familiar with their squirrel neighbours as it enhances the prospect of survival. They say that defending a territory is costly in terms of time and energy, which could be better spent raising a family and gathering food.
It appears that red squirrel neighbours enter into a mutual agreement on boundaries which precludes the need to be aggressive to each other so although a basic rule of nature is competition and survival of the fittest the benefits of some form of agreement has worked its way into the evolution of this species.
The benefits of familiar neighbours outweighed the effects of getting old in terms of survival. At age 5 the survival rate is 59% but if the same neighbours were present they had a 74% chance of surviving a year from age 5. The researchers didn’t find direct cooperation such as working together to fight off an intruder but they appear to have a social relationship with neighbours.
The lead author is Dr Erin Siracusa of the Centre for Research in Animal Behaviour at the University of Exeter. The research was part of the Kluane Red Squirrel Project started at the University of Alberta. Those funding the research include: Natural Sciences and Engineering Research Council of Canada, the National Science Foundation, the American Society of Mammalogists and the Arctic Institute of North America.