Squirrels’ memories are so keen they can remember how they got into a garden bird feeder almost two years after first breaking into it.
Dr Pizza Ka Yee Chow, of the University of Exeter’s Centre for Research in Animal Behaviour, said: “People may try different types of bird feeders to keep the squirrels away, but this research shows grey squirrels can remember tricks for getting food. This might be why grey squirrels can survive very well in towns and cities.”
In the study, five squirrels were given a task identical to one they had tried 22 months earlier, in which they had to press levers to get hazelnuts.
In that first trial, the squirrels improved with practice, taking an average of eight seconds on their first attempt and just two seconds by their final effort.
Trying again after 22 months, they took an average of just three seconds to get the nuts.
Dr Theo Robert, said the new research demonstrates a “very different form of memory”.
He said: “This is not just remembering where things have been left, it shows they can recall techniques they have not used for a long time.”
Squirrels are also are known to put on elaborate bogus “food burying displays”.
The fake burials are to trick potential thieves, such as other squirrels or birds, that they have stored food there.