Birds in Sanskrit Literature stimulating their sexual impulses which leads to simultaneous mating and breeding among them. In other words the Terns would seem to have realised in the course of evolution that their safety and survival in the struggle for existence lies in keeping together and breeding in packed colonies. As a preliminary to mating they indulge in lock-displays and social flights resembling the communal aerial dances of some of the Gulls, e.g. the Herring Gull. The courtship display of mated pairs includes (i) what has been aptly described as a 'fish-flight' where a bird with or with- out a fish is sportingly pursued and overtaken by another; (ii) swift glides from a height; (iii) slow-motion flights; and (iv) parading, bowing, scraping, stretching and 'scissor-billing' when on the ground. Both sexes brood the eggs and young and take part in feeding the latter, and some, like the Sandwitch Tern, are known to 'pool the young' of a colony after they are a few weeks old. They are extremely demonstrative in their affection for young and eggs, for "a human being has only to set foot on a sand-bank for a scene of great excitement to ensue. Sitting birds rise from. the nests, others arrive from the river,...and the air is filled with Terns flashing backwards and forwards and wheeling round and round overhead, their shrill plaintive cries indicating only too surely the presence of the eggs and offspring they seek to protect" (Whistler). They also appear to be very sympathetic towards their fellows that may get into difficulties. If one is killed the others in the neighbourhood will at once come and fly anxiously about uttering their plaintive cries all the time. Salim Ali's explanation of such behaviour when one has been actually shot down. into the river, is that "the unwounded birds think their companion has discovered some food and are anxious to share the spoils" and in the particular circumstances stated it would appear to be correct. Mated Terns, again, are very attentive to each other, and "one of the most charm- ing sights of a visit to a colony is to see one of these little, gentle creatures feed his mate as she sits brooding her eggs". 3. About fifty species of Tern occur throughout the world and India claims no fewer than thirtytwo of them either as winter visitors to her coasts and inland waters or as resident birds. Brief notes on some of the more important Terns found in India e given below: (i) The Indian Whiskered Tern (10") has a velvety black head and neck, ash-grey body and black abdomen. It is a resident bird of lakes and marshes. It breeds in colonies and makes a nest of reeds and rushes which is placed on lotus leaves or other water plants in lakes or swamps. When 346 1. R. M. Lockey in Birds of the Sea (1945), p. 17. 2. J. Fisher in Bird Recognition Vol. 1 (1947), pp. 124-150. According to S. Baker in F.B.I. (Birds), 1929, however, the Sandwitch Tern is very careless of its eggs. 'Pooling the young' refers to the feeding of the young in a colony by the adult birds irrespective of whether the young are their own, i.e., they are all fed in common. 3. T. Gilbert Pearson on the Least Terns (Ternlets) in Birds of America (1936). Terns 347 fishing a whole flock generally works in unison, commencing at the end of a lake and working their way to the other end, when once more they return to their original starting point. In this they resemble the Skimmer who, however flies over the water very low, just a few inches above the surface. The flight is most light and elegant, and the sight of a flock feeding is a really beautiful one. (ii) The Caspian Tern (20") is easily recognised by its great size, large red bill, black legs and feet, black head and grey and white body as it flies singly or in pairs over the larger rivers of India. It breeds on the lakes of Central and Western Asia, and the Mekran Coast within Indian limits. It is often mistaken for a Gull because of its large size and is known as u (a dialectical variant of ?) in Sind after its loud harsh cry. Describing its ways in The Birds of America, W.L. Finley remarks that its greatest anxiety seems to be to keep them (the young) crouching low in the nest, so that they do not run away and get lost in the crowd (of other young from the neighbouring nests). If a young bird did start to run out of the nest, he was immediately pounced upon by his own parents and pecked and beaten until he dropped flat on the ground or hid in the leaves. A similar trait was observed by the ancient Indians as we shall see. (iii) The Gull-billed Tern (15") is rather stoutly built and in point. of body-shape stands intermediate between a Gull and a typical Tern. It is pearl-grey above and pure white below but its stout Gull-like black bill and legs of the same colour help to distinguish it from other Terns of the same size. Its scientific name of 'Gelochelidon nilotica' (lit. 'Laughing Swallow of the Nile') is after its call-notes described by Dr. Ridgway as 'a chattering laugh' (Birds of America). It shows great courage in defend- ing its young. It breeds in Kashmir and other places in India and frequents the larger rivers lakes often singly or in twos and threes. It feeds on small fish and insects and like so many Terns and Gulls, is especially fond of grasshoppers. (iv) The Large Crested Tern (20"), which occurs in several races in India, is practically equal in size to the Caspian Tern but is readily distinguishable from it by the yellow bill and a well-developed, long, black and slightly curved crest. They are coastal birds and one sub-species breeds off the Mekran Coast and another off the Sunderbans in lower Bengal. (v) The Indian River Tern (15"-18") and the allied forms, the Black- bellied Tern (13"-14"), and the Tibetan Tern (15-18") are the com- monest Terns of North Indian rivers and lakes, the first two breeding in large colonies on sand-banks of our rivers, and the third on rivers and lakes of Ladakh and Tibet and winters in India. Other members of the group
- Smythies in Birds of Burma (1940).
