Country diary: a swirl of rooks and jackdaws, maybe 1,000 or more

Marshwood Vale, Dorset: These mixed roosts are a winter arrangement, but there are already signs that they are breaking upRooks and jackdaws come and go with the night, rising and falling in black skeins over the house. They arrive at dusk, with a rush of wings beating the air, and leave before dawn, clattering and cawing. They roost during darkness in the crest of a nearby wood. Numbers have slowly increased since November and there must be nearly 1,000 birds there now.It's easy to tell the two species apart by both appearance and sound. Adult rooks have a bald, greyish-white patch at the base of their large bills, which makes them look like medieval plague doctors wearing beaked masks. Jackdaws are smaller and have a distinctive silvery sheen over the back of their heads and necks, as if wearing a scarf. Close up, you can see their pearly eyes: unsettlingly pale with stark, seed-black pupils. Their calls are different: Jackdaws make a sharp "tchak", like woodblocks being struck smartly together, while rooks have a salty-soft rasping cry. Continue reading...