Clever bird behaviour survey starts
The British Trust for Ornithology (BTO) is asking the public to take part in a national survey of bird intelligence.
From 1 July, the charity is asking people to submit video clips or descriptions of the behaviour of rooks - some of our cleverest garden birds.
Rooks have already demonstrated their intelligence in studies that have tested their ability to solve problems and use tools. This survey will examine if they are able to use these skills in our gardens to solve problems they do not encounter in the wild.
Here, a rook appears to have done exactly that by unhooking a bird feeder in order to gain access to the food inside.
Footage courtesy of John Charles
01 Jul 2014