Most of the crow family have a reputation for evil and mischief, possibly because of the Carrion Crow's habit in days of yore to feed on the dead on battlefields or the gallows. Nowadays they're more likely to be feasting on wildlife killed by cars. I'm fairly convinced that their close cousin, the Magpie, has hugely increased in numbers in recent decades as a result of this food-source. At one time you mostly saw them in thorny scrub, well away from people; nowadays if you travel the roads in early morning, before there's much traffic about, they are the bird you're most likely to encounter, as they feast on anything killed overnight.
The crow family are known to naturalists as Corvids - and very tempting it was to call this post "Corvid 19", as I can sometimes convince myself that there are 19 Rooks in the picture above. It is of course a rookery, where the birds are nesting at present and are probably sitting on eggs by now. There is an old piece of folklore that says that if the Rooks build high in the trees it will be a good summer - and what a load of rubbish that is! They use the same nests year after year.
In winter they gather in even larger numbers at roosts (which are also called rookeries, rather confusingly) often in the company of the smaller Jackdaw. These roosts can contain thousands of birds. They tend to flock together in greater and greater numbers as winter progresses. In the evening they gradually assemble in the fields near the roost site, then, just as it's almost dark they all ascend, as if to some invisible signal, into the treetops. It's one of the great, but little known, wildlife spectacles of these islands. And it's also one of the noisiest as they are very vocal birds.
The fellow above is a Jackdaw, easily recognisable by their smaller size, their light-coloured eye and the grey feathers around the head. Just like me the Jackdaw gets greyer and greyer as it gets older!
Both Jackdaws and Rooks appear to be playful birds, especially on windy days. On the farm where I worked years ago, there was a huge barn and when the wind was in a certain direction they would fly towards the barn sheltering from the wind, then would climb up steeply to the top of its roof where the wind would suddenly catch them and throw them high in the air. They then used to fly back and repeat the process again and again. If they weren't playing then I don't know what they were doing!
When they tired of that game they had another. This involved flying up to the vertical side of the strawstack and hanging on for as long as possible. Again there seemed no practical reason for this behaviour.
Unlike some birds who appear to have an inate ability to build nests, the Rook, who as far as we can tell is one of the more intelligent birds, has but the sketchiest idea of how to construct one. They appear to experiment and by trial and error achieve a large heap of sticks which somehow stays aloft, not only for the nesting season, but right through the year including the winter gales. As I've mentioned elsewhere they steal material from each others nests but never pick up anything that falls to the ground.
According to some of the old farm-workers I used to know, Rooks hanging around the farm in the morning meant that bad weather was on the way. It's difficult to prove this one way or the other but, from their elevated position they could certainly see dark clouds approaching.
Another tale was that if Rooks moved away from a farm it spelled bad luck. As my father pointed out to me once, you'd have to be farming pretty badly if things got so desperate that the Rooks moved on!
There is a (slightly) serious point to the pictures above. A Rook's eyes point forwards so it can't see all around as some birds can and is unaware of what's going on behind. That may be one advantage to their gregarious lifestyle - there's always someone on lookout.
Above is a Carrion Crow with a cruel-looking beak, ideal for tearing apart the dead creatures on which it feeds. A Rook on the other hand has a long, pointed bill with which to probe the newly-ploughed fields for worms and grubs. The other way to tell them apart is the old country saying, "If you sees a lot of Crows together, they be Rooks. But one Rook on his own? Tha's a Crow". It's all down to the way they feed: a Carrion Crow discovering a dead vole or mouse will want it all to itself; whereas Rooks feed mainly on earthworms which are hidden below the surface, so many birds feeding together will soon find the best hunting ground for worms.
Oh, and for those who like those strange collective nouns for birds and animals: a lot of noisy Rooks, all crowded together and chattering and shouting at the same time, is known as a parliament of Rooks. About which I shall say no more.