The Zoologist/4th series, vol 5 (1901)/Issue 726/On the Increase of the Starling and the Hawfinch, Howard
ON THE INCREASE OF THE STARLING AND THE HAWFINCH.
By H.E. Howard, F.Z.S.
That an increased population must very considerably affect the life-history of many of the birds of this country is a fact which. I think, is apparent to all who take an interest in the avifauna of Great Britain. To determine what changes are in progress at the present moment is, however, no easy matter; but still. I think, there are some which can be readily fathomed.
As amongst all animals, so amongst birds, the survival of the fittest plays the most important part in the formation of their history; that is to say, certain species will increase, others will decrease; partly because their habits are not adapted to the changes brought about by civilization, partly as a direct result of the growth of some stronger and opposing species. There is too great a tendency at the present time to seize upon the fact of the decrease of a certain species, and to exaggerate it into a proof that the birds of this country are in a bad way; and, as a rule, the cause is directly attributed to human agency. This tendency—due to what I might term a too superficial observation, combined with the fact that it is far more difficult to determine an increase than a decrease in a certain species—is, to my mind, a great pity, as it is calculated to diminish that scientific observation which, carried on at all seasons of the year, can alone give an insight into those problems of ornithology which the naturalist is constantly called upon to investigate.
The real changes that are in progress are therefore apt to be overlooked, and their effect on the history of certain birds of this country does not appear to be fully appreciated.
In this article I propose to deal with two species that are increasing, with results that, from my own observations, appear likely to accrue. The first of these is the Starling, a bird which probably possesses an energetic force to a greater degree than any other species in this country. The great factors which govern the life of all birds are—first, food; and, secondly, immunity from attack during the nesting season. Climate, of course, also plays an important part, periodical seasons of extreme cold having an appalling effect on certain birds. But Starlings have very little to fear from any of these, their habits being in every way suited to human civilization; their diet is so varied that they are very rarely short of food; their nest is always built in holes, either in houses or trees, and therefore they are practically safe from that pest that follows in the wake of all civilization—the domestic Cat. And what is the result? The same energy which compels them to seek food, compels them also to find somehow or somewhere suitable places to rear their young, the consequence being that some other species has to suffer. For some years past I have watched the struggles enacted between Starlings and Green Woodpeckers for the possession of the latter's nesting-site, and in not a single case have I seen the Woodpeckers able to hold their own. I should like to be able to think that these cases are only local, but cannot do so, as every year, without in any way searching for them, the same struggles, both near habitations and in large woods and forests, are being continually forced upon my notice. The country now appears to be, so to speak, inundated with Starlings. Near the house I was able daily to watch two cases most closely, and to note how the Starlings planned their attack, and the length of time they took to achieve their object.
In the first case the struggle lasted a week; in the second, I was beginning to congratulate myself that at last a Woodpecker had won the day, when one morning I noticed, with great disgust, a Starling, carrying straws in its bill, disappear into the hole, thereby proving that the fight was over. If it was only a pair of Woodpeckers versus a pair of Starlings. I think it very probable that the Woodpeckers would hold their own; but it is not so. A number of Starlings collect on or about the tree in which the Woodpecker is, and they all in their turn mob him, and worry his life, until, tired out, he goes off in the hope of finding some other place where he can nest in safety. It is obvious that Woodpeckers are a class of birds whose habits are clearly not adapted to civilization, while woods and forests are continually decreasing in every direction; trees that show the slightest sign of decay are by the present utilitarian generation immediately felled. In many districts in this part of the country the Pied Woodpecker is barely able to find sufficient suitable trees to make up its daily round. A curious fact about these birds is that, at the same time each morning one can see them arrive at a certain tree, search it thoroughly, and pass on to another, the trees to which they come and go being always identically the same, proving that they have a round they visit daily.
Added to this, we have an increase of a stronger and opposing species, and I cannot but believe that in, comparatively speaking, a short period, extinction thus caused by natural selection is bound to follow.
And how does this apply to the Hawfinch? The increase of these birds is perhaps more remarkable than the Starling, and at first sight more unaccountable. But when we come to examine their habits and life-history, and to see how the conditions now existent apply to them, the cause of their increase becomes more apparent. That there is a very remarkable increase requires very little observation to prove, and to me it has become yearly more interesting. Fifteen years ago I rarely saw this bird; five years ago small parties of five and six were not at all uncommon; and during the winter now I frequently see as many as a dozen under one yew. This year eight pairs nested within half a mile of my house. At this rate of increase the bird will soon rival the Greenfinch in abundance.
Food, of course, gives the limit of numbers, and they depend to a great extent on civilization for their food; and in this fact we shall find, I think, a reason for their increase. As the population grows, so does the need of market-gardens, with an increase in the cultivation of vegetables, and thus more peas are grown, which, from the middle of June to the end of July—that is to say, for the first six weeks after the young are fledged—form their staple food. This time of year used undoubtedly to be the most difficult one for them to procure food. In the winter, contrary to the experience of other birds, they have always a plentiful supply of food. One can then find them feeding on the berries and seeds of holly, yew, and hornbeam, and in that they only eat the kernels, they have an advantage, devouring what other birds discard. They are also better off than they used to be for nesting-sites, the large orchards in fruit-growing districts affording them ample shelter. A very large proportion of the nests I have found have been in apple-trees, which seems to have been the experience of others; and, as a rule, the nests are not far from the ground, and in their size vary to an unusual extent; some, even where I have known the exact spot, being exceedingly hard to see, on account of their being so lightly built; others are large bulky nests, which you can hardly help detecting at once when near the tree; but the orchards are large, and therefore this species has a good chance of rearing its young in safety. It is difficult to forecast how this will affect other species, but the Hawfinch is a pugnacious as well as a very strong bird, and if this rate of increase is maintained—as there is every reason to suppose it will be—then some other weaker species already struggling with the physical conditions of life is bound to suffer; but the result to farmers and fruit-growers is very apparent. At first sight it appears unlikely and almost incredible that a few Hawfinches could do much damage to a field of peas; but if anyone has any doubt on this point, let him watch the birds at work, and see how a family takes up its abode in a field, and how from early in the morning until late at night they are hard at work splitting up the pods; when I think even the most incredulous will be compelled to admit that at least a great deal of damage is done. It remains, however, to the unlucky persons who possess cherry-orchards, and look to them as a source of income, to suffer most from the depredations of this bird, although probably few of them are aware of the fact. For some time I looked upon Hawfinches as birds that did little harm during the mouth of May; as a rule, they appeared to me to feed entirely on the seeds of the oak at this time of year, but I discovered my mistake when looking for the nests. Having watched the birds for some time in and out of a cherry orchard on the borders of a forest between the hours of three and five in the morning. I concluded that they must be nesting in it; I therefore searched every tree, and, having failed to find any trace of a nest. I thought it best to wait and see for what reason the birds visited the orchard. This I did, with the result that before long a pair settled in the tree under which I stood, and began to feed upon the fruit, which at this time of year is just setting. In common with some other species, they appear to be less shy during the breeding season. While standing under a cherrytree. I have watched them at work within six feet of my head, and to see the quick way they pass from branch to branch, and the pieces of what would be cherries falling to the ground, one wonders how it is possible for any fruit to come to maturity at all.
Between three and six in the morning is the best time to watch them feeding—in fact, all observations during spring and summer, to be of any use, ought to be made at that time of the morning. After seven o'clock birds slacken off, and during the day activity amongst them, as compared with the first few hours after dawn, is practically nil. I am much afraid that the Hawfinch will in future become another scourge for the already much to be pitied fruit-grower.
And here, perhaps, it would not be out of place to say a word for those whose existence depends to a great extent on a good fruit crop. How during the month of July can they be expected to conform to the rules and regulations as regards wild birds. No firing of guns, shouting, or any of the wonderful devices you see placed in the trees have the least effect in keeping away the birds. Nothing but killing—and even this to be of any use must be commenced directly the fruit shows any signs of ripening; for, if the birds are once allowed to get out of hand, not even killing will keep away what I can only describe as the vast hordes which assemble round the orchards. Of late there has been too much whining about the imaginary decrease of the birds of this country. It is quite time this ended, and in its place more common sense and closer observation cultivated, as by these means alone can we hope to discover in what direction it is possible for man to facilitate the union of nature and agricultural interests.