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MAY
THE CUCKOO

With the single exception of the nightingale, bird of lovers, no other has been more written of in prose or verse than the so-called "harbinger of spring." This is a foolish name for a visitor that does not reach our shores before, at any rate, the middle of April. Even Whitaker allows us to recognise the coming of spring nearly a month earlier; and for myself, impatient if only for the illusion of Nature's awakening, I date my spring from the ending of the shortest day. Once the days begin to lengthen, it is time to glance at the elms for the return of the rooks and to get out one's fishing-tackle again. Yet the cuckoo comes rarely before the third week of April, save in the fervent imagination of premature heralds, who, giving rein to a fancy winged by desire, or honestly deceived by some village cuckoo clock heard on their country rambles, solemnly write to the papers announcing the inevitable March cuckoo. They know better in the Channel Islands, for in the second week of April, and not before, there are cuckoos in every bush – hundreds of exhausted travellers pausing for strength to complete the rest of their journey to Britain. Not on the return migration in August do the wanderers assemble in the islands, since, having but lately set out, they are not yet weary enough to need the rest. The only district of England in which I have heard of similar gatherings of cuckoos is East Anglia, where, about the time of their arrival, they regularly collect in the bushes and indulge in preliminary gambols before flying north and west.

Cuckoos, then, reach these islands about the third week of April, and they leave us again at the end of the summer, the old birds flying south in July, the younger generation following three or four weeks later. Goodness knows by what extraordinary instinct these young ones know the way. But the young cuckoo is a marvel altogether in the manner of its education, since, when one comes to think of it, it has no upbringing by its own parents and cannot even learn how to cry "Cuckoo!" by example or instruction. Its foster-parents speak another language, and its own folk have ceased from singing by the time it is out of the nest. A good deal has been written about the way in which the note varies, chiefly in the direction of greater harshness and a more staccato and less sustained note, towards the end of the cuckoo's stay. According to the rustic rhyme, it changes its tune in June, which is probably poetic licence rather than the fruits of actual observation. It is, however, commonly agreed that the cuckoo is less often heard as the time of its departure draws near, and the easiest explanation of its silence, once the breeding season is ended, is that the note, being the love-call of a polygamous bird, is no longer needed.

In Australia the female cuckoo is handsomely barred with white, whereas the male is uniformly black; but with our bird it is exceedingly difficult to distinguish one sex from the other on the wing, and, were it not for occasional evidence of females having been shot when actually calling, we might still believe that it is the male only that makes this sound. The note is joyous only in the poet's fancy, just as he has also read sadness into the "sobbing" of the nightingale. There is, indeed, when we consider its life, something fantastic in the hypothesis that the cuckoo can know no trouble in life, merely because it escapes the rigours of our winter. Eternal summer must be a delight, but the cuckoo has to work hard for the privilege, and it must at times be harried to the verge of desperation by the small birds that continually mob it in broad daylight. This behaviour on the part of its pertinacious little neighbours has been the occasion of much futile speculation; but the one certain result of such persecution is to make the cuckoo, along with its fellow-sufferer, the owls, preferably active in the sweet peace of the gloaming, when its puny tyrants are gone to roost. Much heated argument has raged round the real or supposed sentiment that inspires such demonstrations on the part of linnets, sparrows, chaffinches, and other determined hunters of the cuckoo. It seems impossible, when we observe the larger bird's unmistakable desire to win free of them, to attribute friendly feelings to its pursuers. Yet some writers have held the curious belief that, with lingering memories of the days when, a year ago, they devoted themselves to the ugly foster-child, the little birds still regard the stranger with affection. If so, then they have an eccentric way of showing it, and the cuckoo, driven by the chattering little termagants from pillar to post, may well pray to be saved from its friends. On the other hand, even though convinced of their hostility, it is not easy to believe, as some folks tell us, that they mistake the cuckoo for a hawk. Even the human eye, though slower to take note of such differences, can distinguish between the two, and the cuckoo's note would still further undeceive them. The most satisfactory explanation of all perhaps is that the nest memories do in truth survive, not, however, investing the cuckoo with a halo of romance, but rather branding it as an object of suspicion, an interloper, to be driven out of the neighbourhood at all costs ere it has time to billet its offspring on the hard-working residents. All of which is, needless to say, the merest guesswork, since any attempt to interpret the simplest actions of birds is likely to lead us into erroneous conclusions. Yet, of the two, it certainly seems more reasonable to regard the smaller birds as resenting the parasitic habit in the cuckoo than to admit that they can actually welcome the murder of their own offspring to make room in the nest for the ugly changeling foisted on them by this fly-by-night.

On the lucus a non lucendo principle, the cuckoo is chiefly interesting as a parent. The bare fact is that our British kind builds no nest of its own, but puts its eggs out to hatch, choosing for the purpose the nests of numerous small birds which it knows to be suitable. Further investigation of the habits of this not very secretive bird, shows that she first lays her egg on the ground and then carries it in her bill to a neighbouring nest. Whether she first chooses the nest and then lays the egg destined to be hatched in it, or whether she lays each egg when so moved and then hunts about for a home for it, has never been ascertained. The former method seems the more practical of the two. On the other hand, little nests of the right sort are so plentiful in May that, with her mother-instinct to guide her, she could always find one at a few moments' notice. Some people, who are never so happy as when making the wonders of Nature seem still more wonderful than they really are, have declared that the cuckoo lays eggs to match those among which she deposits them, or that, at any rate, she chooses the nests of birds whose eggs approximately resemble her own. I should have liked to believe this, but am unfortunately debarred by the memory of about forty cuckoo's eggs that I took, seven-and-twenty summers ago, in the woods round Dartford Heath. The majority of these were found in hedgesparrows' nests, and the absolute dissimilarity between the great spotted egg of the cuckoo and the little blue egg of its so-called dupe would have impressed even a colour-blind animal. Occasionally, I believe, a blue cuckoo's egg has been found, but such a freak could hardly be the result of design. As a matter of fact, there is no need for any such elaborate deception. Up to the moment of hatching, the little foster-parents have in all probability no suspicion of the trick that has been played on them. Birds do not take deliberate notice of the size or colour of their own eggs. Kearton somewhere relates how he once induced a blackbird to sit on the eggs of a thrush, and a lapwing on those of a redshank. So, too, farmyard hens will hatch the eggs of ducks or game birds and wild birds can even be persuaded to sit on eggs made of painted wood. Why then, since they are so careless of appearances, should the cuckoo go to all manner of trouble to match the eggs of hedgesparrow, robin or warbler? The bird would not notice the difference, and, even if she did, she would probably sit quite as close, if only for the sake of the other eggs of her own laying. Once the ugly nestling is hatched, there comes swift awakening. Yet there is no thought of reprisal or desertion. It looks rather as if the little foster-parents are hypnotised by the uncouth guest, for they see their own young ones elbowed out of the home and continue, with unflagging devotion, to minister to the insatiable appetite of the greedy little murderer. A bird so imbued as the parasitic cuckoo with the Wanderlust would make a very careless parent, and we must therefore perhaps revise our unflattering estimate of its attitude and admit that it does the best it can by its offspring in putting them out to nurse. This habit, unique among British birds, is practised by many others elsewhere, and in particular by the American troupials, or cattle-starlings. One of these indeed goes even farther, since it entrusts its eggs to the care of a nest-building cousin. There are also American cuckoos that build their own nest and incubate their own eggs.

On the whole, our cuckoo is a friend to the farmer, for it destroys vast quantities of hairy caterpillars that no other bird, resident or migratory, would touch. On the other hand, no doubt, the numbers of other small useful birds must suffer, not alone because the cuckoo sucks their eggs, but also because, as has been shown, the rearing of every young cuckoo means the destruction of the legitimate occupants of the nest. So far however as the farmer is concerned, this is probably balanced by the reflection that a single young cuckoo is so rapacious as to need all the insect food available.

The cuckoo, like the woodcock, is supposed to have its forerunner. Just as the small horned owl, which reaches our shores a little in advance of the latter, is popularly known as the "woodcock owl," so also the wryneck, which comes to us about the same time as the first of the cuckoos, goes by the name of "cuckoo-leader." It is never a very conspicuous bird, and appears to be rarer nowadays than formerly. Schoolboys know it best from its habit of hissing like a snake and giving them a rare fright when they cautiously insert a predatory hand in some hollow tree in search of a possible nest. It is in such situations that, along with titmice and some other birds, the wryneck rears its young; and it doubtless owes many an escape to this habit of hissing, accompanied by a vigorous twisting of its neck and the infliction of a sufficient peck, easily mistaken in a moment of panic for the bite of an angry adder. Thus does Nature protect her weaklings.

JUNE
VOICES OF THE NIGHT

The majority of nocturnal animals, more particularly those bent on spoliation, are strangely silent. True, frogs croak in the marshes, bats shrill overhead at so high a pitch that some folks cannot hear them, and owls hoot from their ruins in a fashion that some vote melodious and romantic, while others associate the sound rather with midnight crime and dislike it accordingly. The badger, on the other hand, with the otter and fox – all of them sad thieves from our point of view – have learnt, whatever their primeval habits, to go about their marauding in stealthy silence; and it is only in less settled regions that one hears the jackals barking, the hyænas howling, and the browsing deer whistling through the night watches.

There are, however, two of our native birds, or rather summer visitors, since they leave us in autumn, closely associated with these warm June nights, the stillness of which they break in very different fashion, and these are the nightingale and nightjar. Each is of considerable interest in its own way. It is not to be denied that the churring note of the nightjar is, to ordinary ears, the reverse of attractive, and the bird is not much more pleasing to the eye than to the ear; while the nightingale, on the contrary, produces such sweet sounds as made Izaak Walton marvel what music God could provide for His saints in heaven when He gave such as this to sinners on earth. The suggestion was not wholly his own, since the father of angling borrowed it from a French writer; but he vastly improved on the original, and the passage will long live in the hearts of thousands who care not a jot for his instructions in respect of worms. At the same time, the nightjar, though the less attractive bird of the two, is fully as interesting as its comrade of the summer darkness, and there should be no difficulty in indicating the little that they have in common, as well as much wherein they differ, in both habits and appearance.

Both, then, are birds of sober attire. Indeed of the two, the nightjar, with its soft and delicately pencilled plumage and the conspicuous white spots, is perhaps the handsomer, though, as it is seen only in the gloaming, its quiet beauty is but little appreciated. The unobtrusive dress of the nightingale, on the other hand, is familiar in districts in which the bird abounds, and is commonly quoted, by contrast with its unrivalled voice, as the converse of the gaudy colouring of raucous macaws and parrakeets. As has been said, both these birds are summer migrants, the nightingale arriving on our shores about the middle of April, the nightjar perhaps a fortnight later. Thenceforth, however, their programmes are wholly divergent, for, whereas the nightjars proceed to scatter over the length and breadth of Britain, penetrating even to Ireland in the west and as far north as the Hebrides, the nightingale stops far short of these extremes and leaves whole counties of England, as well as probably the whole of Scotland, and certainly the whole of Ireland, out of its calculations. It is however well known that its range is slowly but surely extending towards the west.

This curiously restricted distribution of the nightingale, indeed, within the limits of its summer home is among the most remarkable of the many problems confronting the student of distribution, and successive ingenious but unconvincing attempts to explain its seeming eccentricity, or at any rate caprice, in the choice of its nesting range only make the confusion worse. Briefly, in spite of a number of doubtful and even suspicious reports of the bird's occurrence outside of these boundaries, it is generally agreed by the soundest observers that its travels do not extend much north of the city of York, or much west of a line drawn through Exeter and Birmingham. By way of complicating the argument, we know, on good authority, that the nightingale's range is equally peculiar elsewhere; and that, whereas it likewise shuns the departments in the extreme west of France, it occurs all over the Peninsula, a region extending considerably farther into the sunset than either Brittany or Cornwall, in both of which it is unknown. No satisfactory explanation of the little visitor's objection to Wild Wales or Cornwall has been found, and it may at once be stated that its capricious distribution cannot be accounted for by any known facts of soil, climate, or vegetation, since the surroundings which it finds suitable in Kent and Sussex are equally to be found down in the West Country, but fail to attract their share of nightingales.

The song of the nightingale, in praise of which volumes have been written, is perhaps more beautiful than that of any other bird, though I have heard wonderful efforts from the mocking-bird in the United States and from the bulbuls along the banks of the Jordan. The latter are sometimes, more especially in poetry, regarded as identical with the nightingale; and, indeed, some ornithologists hold the two to be closely related. What a gap there is between the sobbing cadences of the nightingale and the rasping note of the nightjar, which, with specific reference to a Colonial cousin of that bird Tasmanians ingeniously render as "more pork"! It seems almost ludicrous to include under the head of birdsong not only the music of the nightingale, but also the croak of the raven and the booming note of the ostrich. Yet these also are the love-songs of their kind, and the hen ostrich doubtless finds more music in the thunderous note of her lord than in the faint melody of such song-birds as her native Africa provides. The nightingale sings to his mate while she is sitting on her olive-green eggs perching on a low branch of the tree, at foot of which the slender nest is hidden in the undergrowth. So much is known to every schoolboy who is too often guided by the sound on his errand of plunder; and why the song of this particular warbler should have been described by so many writers as one of sadness, seeing that it is associated with the most joyous days in the bird's year, passes comprehension. So obviously is its object to hearten the female in her long and patient vigil that as soon as the young are hatched the male's voice breaks like that of other choristers to a guttural croak. It is said, indeed – though so cruel an experiment would not appeal to many – that if the nest be destroyed just as the young are hatched the bird recovers all his sweetness of voice and sings anew while another home is built.

Although poetic licence has ascribed the song to the female, it is the male nightingale only that sings, and for the purpose aforementioned. The note of the nightjar, on the other hand, is equally uttered by both sexes, and both also have the curious habit of repeatedly clapping the wings for several minutes together. They moreover share the business of incubation, taking day and night duty on the eggs, which, two in number, are laid on the bare ground without any pretence of a nest, and generally on open commons in the neighbourhood of patches of fern-brake. Like the owls, these birds sleep during the day and are active only when the sun goes down. It is this habit of seeking their insect food only in the gloaming which makes nightjars among the most difficult of birds to study from life, and all accounts of their feeding habits must therefore be received with caution, particularly that which compares the bristles on the mouth with baleen in whales, serving as a sort of strainer for the capture of minute flying prey. This is an interesting suggestion, and may even be sober fact; but its adoption would necessitate the bird flying open-mouthed among the oaks and other trees beneath which it finds the yellow underwings and cockchafers on which it feeds, and I have more than once watched it hunting its victims with the beak closed. I noticed this particularly when camping in the backwoods of Eastern Canada where the bird goes by the name of nighthawk.

In all probability its food consists exclusively of insects, though exceptional cases have been noted in which the young birds had evidently been fed on seeds. The popular error which charges it with stealing the milk of ewes and goats, from which it derives the undeserved name of "goat-sucker," with its equivalent in several Continental languages, is another result of the imperfect light in which it is commonly observed. Needless to say, there is no truth whatever in the accusation, for the nightjar would find no more pleasure in drinking milk than we should in eating moths.

Here, then, are two night-voices of very different calibre. These are not our only birds that break the silence on moonlight nights in June. The common thrush often sings far into the night, and the sedge-warbler is a persistent caroller that has often been mistaken for the nightingale. The difference in this respect between the two subjects of these remarks is that the nightjar is invariably silent all through the day, whereas the nightingale sings joyously at all hours. It is only because his splendid music is more marked in the comparative silence of the night, with little or no competition, that his daylight concert is often overlooked.