Throughout April the little cock sunbirds deliver themselves of their vigorous canary-like song.  The bulbuls tinkle as blithely as ever.  Ioras, pied wagtails, pied chats, and wood-shrikes continue to contribute their not unworthy items to the minstrelsy of the Indian countryside.  The robins, having by now found their true notes, are singing sweetly and softly.  The white-eyes are no longer content to utter their usual cheeping call, the cocks give vent to an exquisite warble and thereby proclaim the advent of the nesting season.  The towee, towee, towee, of the tailor-bird, more penetrating than melodious, grows daily more vigorous, reminding us that we may now hopefully search for his nest.  Among the less pleasing sounds that fill the welkin are the tonk, tonk, tonk of the coppersmith, the kutur, kutur, kuturuk of the green barbet, and the calls of the various cuckoos that summer in the plains of Northern India.  The calls of these cuckoos, although frequently heard in April, are uttered more continuously in May, accordingly they are described in the calendar for that month.

The owls, of course, lift up their voices, particularly on moonlight nights.  The nightjars are as vociferous as they were in March; their breeding season is now at its height.

In the hills the woods resound with the cheerful double note of the European cuckoo (Cuculus canorus).  This bird is occasionally heard in the plains of the Punjab in April, and again from July to September, when it no longer calls in the Himalayas.  This fact, coupled with the records of the presence of the European cuckoo in Central India in June and July, lends support to the theory that the birds which enliven the Himalayas in spring go south in July and winter in the Central Provinces.  Cuckoos, at seasons when they are silent, are apt to be overlooked, or mistaken for shikras.

Ornithologists stationed in Central India will render a service to science if they keep a sharp look-out for European cuckoos and record the results of their observations.  In this way alone can the above theory be proved or disproved.

By the middle of the month most of the rollers have settled down to domestic duties, and in consequence are less noisy than they were when courting.  Their irritating grating cries are now largely replaced by harsh tshocks of delight, each tshock being accompanied by a decisive movement of the tail.  The cause of these interjections expressing delight is a clutch of white eggs or a brood of young birds, hidden in a hole in a tree or a building.

April is a month in which the pulse of bird life beats very vigorously in India.  He who, braving the heat, watches closely the doings of the feathered folk will be rewarded by the discovery of at least thirty different kinds of nests.  Hence, it is evident that the calendar for this month, unless it is to attain very large dimensions, must be a mere catalogue of nesting species.  The compiler of the calendar has to face an embarrass de richesses.