THE CUCKOO.*
Ma. CHANCE has solved one problem and created another. He was attracted, years ago, by the mystery of tho cuckoo. How did she lay her eggs ? How many did she lay ? How did she choose the nest to lay them in ? He set out in 1918 to get the answer to these questions, and found it in 1920 and 1921. He began by establishing the fact that a female cuckoo returning year after year to this country, and probably to the same spot, will arrogate to herself a certain area within which she will control all the nests of the species she chooses as fosterers. for her eggs, whether they be meadow pipits, reed warblers, hedge-sparrows or some other bird—for she limits herself to one species, certainly for season after season, probably for life. In this area she becomes what Mr. Chance calls a " dominant " cuckoo. And the number of eggs she lays depends on the number of nests she finds waiting for her—that is, with eggs not yet incubated. Mr. Chance proved this by finding all the meadow pipits' nests in an area dominated by a particular cuckoo, whom he calls Cuckoo A, and by taking the clutches as they were laid, so that the parent birds were forced to nest again, which they would do four or five times. In 1920 he thus induced Cuckoo A to lay twenty-one eggs, and in 1921, by stopping the supply of new nests, limited her to fifteen. In the course of his watching he discovered other facts. He found that the female cuckoo would get to know the progress of every nest in her area, and would watch a nest for hours, motionless in a tree, before laying. Sho would then glide down, remove one of the fosterer's eggs, and lay one of her own in the nest. to replace it. She did not carry her egg in her beak, as some people have believed. This process of watching a nest, Mr. Chance holds, induces a cuckoo to " conceive " an egg, and she only conceives " an egg when she has chosen a nest inviting her, so to speak, to do so.
So much for the mystery to which Mr. Chance has found the key. Will he help to solve his other problem ? He has created it, probably, unwittingly. He tells us, incidentally, that he has taken hundreds of cuckoos' eggs, and he speaks of other collectors as having done the same. What of the Wild Birds Protection Acts ? It is true that the cuckoo's eggs are not protected in every county, but the bird itself is protected in all. And what is the use of making it illegal to kill the parent bird if collectors are allowed to destroy all her eggs ? For this is what in many cases they are doing to-day, and not only with the cuckoo, but with other birds. Is it not time to amend the lasi ?
Previous page
