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The Rook lives in flocks and breeds in great colonies. Its nest is smaller and looser than that of the Hooded Crow. Five or six nests one above another, are often found in one tree—sometimes as many as eighteen. It pairs somewhat late, in Hungary, but already in April may be found three to five eggs of a pale green colour spotted with grey and blue. These are smaller than those of the Hooded Crow.

The Rook spends the greater part of its life in its native home, often in huge crowds, numbering many thousands, which divide up during the day to seek food in different parts of the neighbourhood. During the breeding time they are divided according to the breeding places. This bird is the most zealous follower of the ploughman, and by its great number destroys an enormous quantity of noxious creatures—the cockchafer being its most coveted delicacy. It covers, with its flocks, the freshly ploughed field, and if they are sown, picks up the grains that are lying about. It bores into the soft earth of the meadows and cornfields, for destructive grubs, and pulls up the withered plants in order to secure the caterpillar or wireworm which has destroyed the roots. This has caused the Rook to be suspected of plundering the fields, but the question has not yet been settled, and the general inclination is in the bird’s favour. The fact is that even in Hungary, where the Rook exists in millions, the people generally are indifferent about it. Early sowing, while there is

CHIEFLY USEFUL.

THE ROOK. AN OLD AND A YOUNG BIRD.

sufficient insect food for the birds, is the best protection from its mischief, and this is good for the services it performs.

A knowledge of the habits of the Rook is important, because the bird is closely associated with husbandry, and with its well organised work deeply affects the interests of the husbandman. While the Hooded Crow roams about the district with the Jackdaw, thousands of Rooks cover the corn-fields; they settle also on fallow ground, on the freshly ploughed field, on the sprouting crops, and on the turnip-field. It is this appearance in vast numbers which mainly distinguishes the Rook from the Hooded Crow, which otherwise its habits closely resemble.

In regard to this bird also, different views are held. Whilst the scientific agriculturist considers it useful, the old-fashioned husbandman is convinced that it is harmful. Here again, therefore, must a just verdict be given, between two opposing parties—but this verdict must be impartial. Various things are said of the Rook—but it is not true that it picks the seed out of the earth, so that the spoiled seed has to be ploughed in again. It only takes the seed which has been imperfectly covered by the harrow,—and the reploughing is only an empty complaint, for no one ever heard tell of a particular village, or farm, where reploughing had to be performed on account of the Rooks. The farmer who keeps his eyes open before he gives an opinion knows that the Rook digs his beak into the ground because he hopes to find worms there. Sometimes it is shot, in order to be set up as a scarecrow, but they say nothing of what may be found in its crop, should it be opened; this, however, is just what is necessary in order to ascertain the truth—although the other conditions of its life must also be taken into account.

It is easy to observe the behaviour of Rooks, because they always move and act in flocks. These flocks are dissolved only in cold snowy winters, when the birds, tired of the cold and lack of food, come into the villages. When the early spring ploughing begins, part of them follow the plough; the flock spreads itself over the freshly ploughed land and they snap up the grubs of the destructive insects which escape from the newly-turned clods. This then is useful work. They also settle on the sown land and pick up the seeds which the harrow has left on the surface, but at the same time devour the insects which the harrow has turned up. There is no harm in this. In a short time the full spring has come and the immature insects have developed into other forms—then the Rook begins to think of building its nest. Its young are not fed on seeds, for at that time there are none to be had, but exclusively on insects—which again is a great and useful work. Then the flock spreads over the neighbourhood, leaving their sleeping-place in the morning in a body, and betaking themselves to different parts of the district; and it may be remembered that separate flocks repeatedly visit the same spot, and work there; as, for instance, one point in a great stretch of cornland, where in the track of the birds lie many uprooted plants, which the farmer generally looks upon as due to the mischief of the Rooks. When insect life has become stronger, they settle on the meadows, where they eagerly hunt for crickets and grasshoppers; then they return to the ploughed fields and destroy the insects that have been disturbed—and this is useful work. It is true that later on they visit any heaps of cut corn that may lie in their way, and in this way do harm, but the greater number of the flock pick up the fallen grains in the stubble field, and a few follow the carts which carry the corn, and pick up any that is dropped. There is no harm in this, as these ears would in any case be lost to the farmer. At the time of the hay harvest they settle on the ridges of cut grass and hunt for crickets and grasshoppers, for these creatures have then no cover, and easily fall a prey to the birds. The Rook also attacks the young maize and fruit, but it has not skill in this respect and cannot do much harm. The harm done is outweighed a thousandfold by the good which it does in the destruction of insects. The black army of birds lights also upon the turnip crops just at the time when these valuable plants are covered with masses of the “turnip caterpillar.” By the destruction of this pest they do the farmer invaluable service.

This sanitary work continues into the late autumn as long as the caterpillars, the Rook’s favourite food, remain. The Rook may do serious damage during the autumn sowing, especially if it is thin, and sown and harrowed so late that the caterpillars have disappeared, not so much, however, that the field must be ploughed up; at the worst there would remain only one or two unproductive spots, and we know that corn grows in tufts, and if it is not thinned by the Rooks it must be done by the farmer, so that the corn is not choked by its own abundance.

When the hard part of winter comes, the flocks of Rooks seek towns and villages, where they spend the nights on the roofs of houses in order to shelter themselves from the icy wind; during the day they steal from the barns and granaries, or, if the opportunity offers, they get at the bundles of straw which they pull about to try and find a stray ear of corn.

This much is certain that the principal food of the Rook consists of insects and grubs, which it gets not only from the surface of the earth, but also from beneath it, when the bird sees from the colour of the fading plant that a grub is gnawing at its root. This is the meaning of the uprooted plants; and why one flock after another so often visits the same cornfields. It is a sure sign that the wireworm or some similar pest is busy with its depredations. Here again the work of the Rook is a blessing.

There are neighbourhoods where the farmer makes a great fuss about a grain or two of wheat or maize, as if he must be ruined by the damage. I repeat that the bird has earned its few grains by its other work; indeed, without its useful services these grains would probably never have grown.

The lesson we learn then is as follows:—The Rook lives principally and preferably on insects, grubs and worms, and so long as these are procurable, it does not look for grain—therefore, the spring sowing should be performed as late as possible, when the insects have developed, and the Rook can find its natural food; in autumn the sowing should be done as early as possible while there are still some insects to be found. The further actions of this bird are protective, for it attacks the gnawing maggots that live in the ground. These facts can be verified by dissection of the bird, when the stomach is often found to be full of wire-worms.

None the less researches into the habits of the rook require to be more thoroughly worked out, and this must not be lost sight of.

. . . . . . . . . . .

I asked a tenant farmer in our own Midlands his views on the subject of Rooks and the following, with some slight editing of my own, was what he sent me. I give it in full as although there may be some repetition of the foregoing statements, it has special interest as coming from one of our English farmers.

A recent writer from the sportsman’s point of view speaks of the Rook as “this black robber,” and he says that there is no practical difference of opinion as to the question whether his benefits outweigh his depredations. Now, as a farmer, I confidently affirm that he does much more good than harm. He will sometimes uproot vegetables in getting at the worms round their roots. It is true also that he often robs the nests of the pheasant and the partridge; but, as I could easily show, he does far more good to the general community by furthering the labours of agriculturists, on whom so much depends, than harm to the sport of our leisured classes.

A more social bird even than the gregarious starling, he flies in flocks, feeds in flocks, and builds in flocks. His everyday life may appear to be an uneventful one to the outside world, and most commonplace; yet it is full of adventure and of joy tempered with sorrows. Apparently a grave bird, he is brimful of humour and, at times, as full of play as a titmouse. Like all other links in the seemingly endless chain of nature, he is the victim of circumstances: without much ado he could count up his sincere friends, but his enemies are beyond his conception of numbers.

From his winter homing quarters he comes with his company during February to inspect the colony of breeding nests which he regards as his peculiar domain, going back as night approaches to his sleeping-place until all is ready for the family life to begin. Rookeries vary, of course, greatly in size; one may be as a city or large town, again there will be a village, and here and there a small hamlet. There are in my own fields one of about a hundred and thirty nests, one of sixty, one of eight, and another of four nests. Of these latter I have some views of my own. I believe them to be those of odd and outlawed individuals who follow the other companies hither, but are socially considered as pariahs. My nearest neighbours are those of the sixty-two-nest village, and my last census-taking records about sixty-two married couples and thirty-six or more odd or unmated birds. These are all, of course, adult birds, their numbers reckoned before the young were hatched out.

The odd birds may some of them be outlaws, as I said before, but the majority of them are not vagabonds by any means. They only happen to belong to that numerous enough class amongst humans—those who have been forced by some just cause or impediment into a life of celibacy. As the rook does not mate until it is nearly two years old, a number of the single birds are, therefore, simply lusty young bachelors. The few individuals whom I sum up as ne’er-do-weels or unfortunates—I know personally three of these at the present moment—are to be recognised by the shabby, neglected, and generally unkempt appearance of their plumage, and some other of the many outward signs of a past henpecked existence. I am ignorant of the life history of these; perhaps if we knew all about them we should look upon them as objects of pity rather than of reproach. Now and again I notice that a few old birds in our colony appear to be dissatisfied with everybody and everything; and imaginary grievances, political and social, often lead to a segregation scheme. This is how I have accounted for my hamlet of four nests. The general run of our odd, or celibate, birds is, however, good in character; they help in the building of the nests and even in feeding the sitting birds. For the wedded pairs April is a most trying time: if the season be a dry one, or frost sets in, food is scarce. Insects and worms are deep in the earth; the farmer is engaged in sowing his spring corn, oats, and barley. The rooks prefer a diet of insects, worms and grubs, but these are hard to get at times; the spring beans are just peeping through, and the sitting hen asks for food. The cock bird ventures too long in the beanfield, and as he skims over the hedge with a bean or two in his pouch a shot is heard; the faithful mate of the sitting bird is brought down to mother earth, and the farmer feels that he has one enemy the less. Personally I would not shoot a bird if you gave me a sovereign for it. The old bird may, and does, grieve, but the news of her loss is soon at the rookery, and her food is brought to her by a new mate. Thus there is a place taken in the rookery by one of our odd birds, and there is a bachelor less in the community. I have known many a bird die about this time through over-zeal—a slave to love and duty. If April prove seasonable and mild with showers, worms are plentiful, and the farmer’s gun remains in its place over the kitchen chimneypiece.

Often during the building season the rookery is disturbed by discordant notes, accompanied by a great fluttering of wings; there is a big row in the township; not a duel over a “squaw”: the rook is a philosopher, and the ritual of love-making and matrimony are of the simplest. The bother will be over divergent interests or a disputed claim, for there is a recognised right of property—not ground-rent to pay, but a specified limit for nest-room has been accorded. The trouble occurs mostly with young birds wishing to place their nests too near to an old nest. A parish council is called, with the result that the disputants’ nests are soon scattered to the winds, and the claimant and the defendant may both have to begin a new foundation. Sometimes there is a disturbance on a more limited scale: one between very near neighbours or blood-relations—a family jar, in fact. One pair of birds do their very best to pull the sticks from the nest of another pair: each of the contending parties will do all they can to prevent the other from building.

As to the nests, we all know how busily the rooks set to work to repair these after a gale of wind has wrought some havoc in their colonies; but I do not think it is equally well known that they are curiously weather-wise, and they scent the coming storm and set to work to repair and strengthen before the imminent gale has been evident to the farmer. I have noticed that fact; the Rook’s powers of sight and hearing are remarkable.

At the end of the breeding-season comes the farmers’ rook-shooting, which I, for one, never take part in: I have too much regard for the labours of both the adult and the young birds. About the roots of each of the turnip-plants there may gather scores of wireworms, which eat the turnips; in the crops of young birds which have been shot are found myriads of these wireworms, or it may be that they are filled with grubs of various sorts, the larvæ of cockchafers, etc. In fact, in my opinion—that of a tenant farmer who is forced to make things pay—all the Rook’s acts of depredation ought to be forgotten if we carefully consider the great services he renders to the agriculturist. Beetles, tipula (Daddy Longlegs grubs), warble grubs, oak-leaf roller caterpillars, and the caterpillars of the diamond-backed moth he devours. The game-preserver may grudge the birds their plundering of his nests, but the farmer is in gratitude bound to spare them. A lot of young birds at the rook-shooting time are still unable to take a flight of any distance, but others are, happily for themselves, able to fly well. I am persuaded that the old parent birds often—foreseeing a shooting raid—get these out of the way, and so they secure life for a number of their young who might have been sacrificed. They betake themselves in parties to their rootings about the elms upon outlying pastures. Daily they grow stronger on the wing, and learn the ways and means of living.

Like all long-lived creatures, the Rook is temperate in eating, and he is capable of going a long time without food—a faculty which stands him in good stead during hard winters. In a long frost or a prolonged drought he is a most determined robber, and when he is on what he knows to be forbidden ground, he posts a sentinel to give warning of the approaching farmer or watcher. He is known to take the eggs of such favourite birds as the thrush and the blackbird, whose nests are open, and therefore soon discovered and plundered. But this is no doubt where his proper food is scarce; and if man had not been so eager in the destruction of some of our birds of prey, who are the natural enemies of him and his, Rooks would be less plentiful in some districts. Still, I for one have no desire to see their numbers decrease, so certain am I of their value; and I believe this bird will become even more valuable as time goes on.

The Rook is somewhat smaller than the Hooded Crow; the beak more slender, rather straighter; the base of it in mature age bare, and covered with a kind of white scurf. The entire bird is black with a steely-blue and purple gloss. The feet black and thick, the claws strong, the sole rough; it walks better than the Hooded Crow. The beak of the young bird is not bare, the nostrils being covered with bristly feathers. The bareness first appears when the bird begins to dig in the ground for its food.

The open nest tempts the Rook.