Corvidae

There are eight native species of corvid, of which we have six on the reserve’s species lists.

Five of them, carrion crow, rook, jackdaw, magpie and jay are residents that nest and rear families in the reserve. The sixth, raven, is a passer-by, probably en-route to the Westbury hills or Avoncliff, where they are known to nest.

Carrion crow (Corvus corone); rook (Corvus frugilegus); jackdaw (Corvus monedula); raven (Corvus corax); magpie (Pica pica); jay (Garrulus glandarius)

The Corvidae are a family of 135 species of passerines (perching birds), known for their remarkable intelligence. Their brain-to-body mass ratio is equal to that of the great apes, whales and dolphins, and only slightly lower than our own.

Magpies can recognize their own image in a mirror, a feat of which only some of the apes (including Homo sapiens), bottlenose dolphins and Asian elephants are capable. Crows and rooks have been observed making and using simple tools to solve complex problems; a tame jackdaw in Italy was trained by thieves to steal money from cash machines; jays exhibit astonishing memory skills by remembering where they buried thousands of acorns.

Corvidae intelligence is believed to be boosted by environmental factors. Firstly, few corvid species migrate. None of our native corvids do, and they therefore have had to adapt to our harsh winter conditions in which survival requires higher intelligence and quicker thinking. Secondly, they are omnivorous; they enter, explore and utilise a wide range of habitat in search of food. If you watch rooks feeding in a field, you can see that they are experimenting, turning things over, trying things out.

Most corvids live in large highly organised social groups. There, their young play together, always a learning process in the childhood of any species. The fledglings mature slowly, acquiring the skills necessary to manage life in a socially stratified community.

We are inclined to see corvids as nest raiders and noisy bird-table pirates. We don’t view them with the same affection we reserve for bluetits and blackbirds. There is nothing very cuddly about a mad-eyed jackdaw, particularly if it is bullying your garden’s songbirds.

But corvids are a successful family of intelligent species busy finding ways to survive in an increasingly difficult and dangerous world. Respect.