Page:The British Warblers A History with Problems of Their Lives - 2 of 9.djvu/39

 his wings and spreads out his tail, hops hurriedly from branch to branch, all the while uttering a curious squeaking note ending with a rattling noise in his throat; then, suddenly starting off in pursuit, he darts in and out of the trees, singing hurriedly as he flies, and on coining up to his rival seizes him, and they both tumble over and over in the air or on the ground. Sometimes, however, changing his mind in the middle of the pursuit, he turns suddenly in the air and returns quietly to his territory. To notice his behaviour towards other species who trespass in the same manner is interesting. I have seen a territory invaded by a family of Blue Tits numbering eight or nine; these Blue Tits passed the same way on their travels for three consecutive mornings almost at the same time. This seemed to be a grievance and a source of real annoyance to this particular male, but he was evidently afraid of their numbers. Darting about, he would spread his tail and rapidly jerk his wings, now and again chasing an isolated member of the family in a half-hearted sort of way, sometimes even venting his anger on a solitary Whitethroat, but finally, leaving the Tits in possession, he would retire to the other end of his territory, from whence he would only return after they had departed.

On the approach of a Hawk he will sometimes fly out of the tree he is in, beating the air very slowly with his wings, hanging his legs down, and uttering his high, squeaking note; his behaviour being in every way similar to that during courtship. He keeps, in fact, a very close watch on all birds that pass near him, frequently chasing Cuckoos (Cuculus canorus) determinedly away, and even if he gets a glimpse through the foliage of a bird passing above him he starts off in pursuit. But he is not so bold as he at first sight appears, for should the stranger, resenting his pursuit, turn and face him he immediately retires.

During incubation the female leaves her nest as little as possible, and evidently has regular times for so doing; frequently between 5.30 and 6.30 in the morning.