There is a saying amongst birdwatchers that if you see a single “crow” it is likely to be a carrion crow or hooded crow. If you see a number of crows then they are likely to be rooks. However the rook is an unusual bird by any standards such as I found out last year. I was in the hide at Udale bay near Cromarty and spied a single “crow” on the tideline. It was foraging among some mallard and wigeon and I mentally put it down as a carrion crow as it had no grey feathers which would have made it a hooded crow. Binoculars revealed that it was in fact a single, adult rook – so much for generalisations. This is all part of the enigma that is the rook as is the fact that they are now coming into bird tables to feed amongst the wood pigeons and many smaller birds. The vast majority of rooks are very much social birds all the year round from the sometimes huge rookeries to the winter roosts. In the winter they may join up with lower numbers of jackdaws.
In contrast, particularly at this time of the year, you may find one or two adult rooks on bird tables and, sometimes, individual juvenile rooks. Such was the case last week with the bird on a bird table in a local garden. You could just see the suggestion of the bald patch beginning to form around the base of the beak and this area is large and conspicuous in the adults. Whilst adult rooks may appear at a distance to be jet black in practice, and close to, they often have varying hues of colour such as iridescent dark green or purple. The juvenile bird on the bird table was just beginning to get some of this colour variation.
There are large areas of the Highlands where the rook is absent as a breeding bird although in the North East it has the highest densities and largest colonies in Britain, and probably in the whole of Europe. The rook has been persecuted over very many years, even in the Highlands, and yet has maintained its overall numbers despite the various ways of killing them. This persecution has been linked with the belief that such large numbers of birds adversely affect crops by damaging and uprooting young plants. In contrast they do take very many insects, some of which are detrimental to the farmer’s crops. Accordingly there is a General Licence for farmers, or their representatives, to control the numbers of rooks. There has been an organised culling in the past with birds shot at their colonies or when gathering for their huge roosts in the winter months. Ironically where such shooting occurs numbers of birds simply come into the area from other rookeries or winter numbers that have not been persecuted. In this way the overall numbers of rooks have been maintained with an estimated between 300,000 and 500,000 nests in Scotland as a whole. However, there has been a suggestion that the numbers have slightly declined in the last few years, perhaps owing to changes in agricultural techniques. Whilst the General Licence allows shooting there has to be a sound reason for the killing. It is not sufficient just to say that there is a general licence so we will shoot them. For example in the past rooks, especially the young so called tenderer birds, were killed to make rook pie or pudding. It was also very much a favourite for adding to other ingredients in such pies. Shooting for this purpose, namely eating, is not a sufficient reason for culling although, no doubt, it still goes on in some places.