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989. :- T. cristatus, Steph. :- Jerdon's Birds of India, Vol. II, p. 842 ; Butler, Deccan, Stray Feathers, Vol. IX, p. 441; Murray's Vertebrate Zoology of Sind, p. 322.

The Large Sea Tern.
 

Length, 17 to 18 ; wing, 13 to 14 ; tail, 7 ; tarsus, 1.25 ; bill at front, 2.5.

Bill pale yellow ; irides dark brown ; legs black.

Head, with the longish occipital crest, deep glossy-black ; forehead, lores, ear-coverts, nape, and all the lower parts silky-white ; back, wings and tail, rather darkish silvery-grey; edge of the wing and tips of the secondaries white; quills dark at the base and tip, hoary or silvery toward the terminal portion, with the inner web and shafts white internally, diminishing in quantity from the first.

The Large Sea Tern is very common at Kurrachee and all along the sea coast. It breeds during April and May, on islands in the Persian Gulf, in company with many other species of Terns. Boat loads of eggs are annually brought into Kurrachee. The eggs are broad ovals, much pointed at one end ; the ground color varies from pale buff to warm salmon color; the markings are of two colors :- dark burnt sienna and pale inky-purple. They measure 2.45 by 1.7.

Verzeich, p. 80 ; Hume, Nests and Eggs Ind. B. p. 655 ; id., Str. F. i. p. 283 ; iv. p. 470 ; Saunders, P. Z. S. 1876; p. 657 ; Hume, Str. F. viii. p. 116; Parker, Str. F. ix. p. 490; Legge, B. Ceylon, p. 102; Murray, Vert., Zool., Sind, p. 322. Sterna cristata, Steph, in Shaw's Gen. Zool. xiii. i. p. 146. Sterna velox, Rupp., Atlas p. 21, t. 13., Thalasseus cristatus, Jerd., B. Ind. ii. p. 842; Blyth, B. Burm. p. 163. Thalasseus Bergii, David, et Oust. Ois Chine, p. 523. -

The Large Crested Sea Tern.
 

Forehead, lores, sides of the face, neck in front and behind, chin, throat, breast, and all the lower parts white; crown of the head, including the eye, crest and nape glossy black; back, wings and tail dusky grey ; inner webs of primaries next the shaft dark brown, the margins white ; inner primaries uni­colorous silvery or hoary grey, margined with white; secondaries white on their inner webs and tips. Bill pale yellow; irides dark brown ; legs and feet black.

Length. - 17.0 to 18.5 inches ;'wing 14.0 to 14.6; bill at front 2.6 to 2.8.

Hab. - Coasts of India generally to the Persian Gulf. Occurs commonly in the Kurrachee harbour, along the Mekran Coast and the Persian Gulf, Burmah and Ceylon. Breeds in the Gulf of Oman, on the Island of Astola, nearly opposite Jask, whence thousands of eggs have been collected during May and June. The eggs are typically broad ovals, strongly pointed towards the small end, but considerably elongated. Varieties are not uncommon. The ground colour varies from white, greenish and pinkish white to pale buff, pale yellowish, and again pale pinkish stone colour to the richest and warmest salmon pink ; the markings are of two colours, an intensely deep burnt sienna brown, often quite black in its intensity, and a pale inky purple, which has an appearance of lying beneath the surface of the shell. In some eggs the inky purple markings are almost entirely wanting, in others more numerous and extensive than the dark ones. In others these dark markings are comparatively thinly sprinkled or dense ; again there are some with huge blotches and spots about the larger end. The eggs vary from 2.3 inches to 2.71 in length and 1.63 to 1.78 in breadth; the average of 2 dozens was 2.45 X 1.71.

The Large Crested Tern.

Sterna bergii, Licht. Verz. Doubl. p. 80 (1823): Hume, S. F. i, p. 283; ii, p. 50; iv, p. 470; Butler, S. F. v, p. 298 ; Hume & Dav. S. F. vi, p. 493; Hume, Cat. no. 989 ; Legge, Birds Ceyl. p. 1026; Vidal, S. F. ix, p. 95 ; Butler, ibid. p. 441 ; Barker, ibid. p. 490 ; Oates, B. B. ii, p. 428 ; id. in Hume's N. & E. 2nd ed. iii, p. 297; Barnes, Birds Bom. p. 431 ; id. Jour. Bom. N. H. Soc. vi, p. 293, fig. 989: Saunders, Cat. B. M. xxv, p. 89. Sterna cristata, Steph. in Shaw's Gen. Zool. xiii, pt. 1, p. 146 (1825); nee Swainson. Sterna velox, Cretzschm. in Rupp. Atlas, p. 21, t. 13 (1826). Thalasseus cristatus, Blyth, Cat. p. 291; Jerdon, B. I. iii, p. 842 ; Hume, Ibis, 1870, p. 437.

The Large Sea-Tern, Jerdon.
 

The Coloration resembles that of S. media, except that the present species has a white frontal band and broader white lores, that the black only descends to the level of the lower edge of the orbit, that the crest is rather more distinct, and above all that the mantle is much darker at all seasons, being grey with a lilac tinge. In the young the quills are greyish brown with white inner borders, and the upper parts much mixed with brown.

Bill pale yellow ; irides deep brown ; legs and feet black ; soles yellowish.

Length 21; tail 6.5 to 7.5, depth of fork 3 to 3.5 ; wing 15 ; tarsus 1.25 ; bill from gape 3.6.

Distribution. The coasts of the Indian Ocean and Polynesia, also the west coast of S. Africa, the Red Sea, and the China Sea. Abundant on the Makran coast and at the Laccadives. and generally distributed, often in considerable numbers, throughout the coasts of India and Ceylon, less common on the Burmese coast.

Habits, &c. This large Tern has very similar habits to those of S. media, and is thoroughly marine, often fishing far from the shore. It has been found breeding in Ceylon and, in large numbers, in May and June on the island of Astola, off the Makran coast, where the nests, as described by Butler, are small holes scratched in the sand, several close together, each containing one to three eggs, which are generally pinkish buff varying to greenish grey, very beautifully blotched, spotted, or streaked with blackish, red-brown, and inky purple, and measuring on an average 2.45 by 1.71.

The Large Crested Sea-Tern.

Male 19 1/2" to 21"; 14 oz to 1 lb. Female 14 oz-to 1 lb. Less black- Bill Pale yellow. Resembles S. media, but has a white frontal band and broader white lores. Mantle grey, tinged lilac. Long black crest. Face, nape, and below silky white. Tips of secondaries white.— In winter: Crown mottled white, and some of the nuchal feathers with white tips. Indian Ocean and Polynesia, also west coast of S. Africa, the Red Sea, and China Sea up to Japan, Australia, but not New Zealand. Common throughout India and Ceylon. One to three eggs (2.45 x 1.71), greenish, blotched and spotted brown and purple. (J. 989. B. 1502.) See illustration, p. 225.

Also S. bernsteini. 17". Legs black. Bill olive, tip yellow. Forehead and lores white. Crest-feathers black and white. Mantle pale grey. Rump white. The Moluccas, Chagos Archipelago, Seychelles, Rodrigues, and Mascarene Islands.

S. frontalis. 16" to 17". Legs red-brown. Bill black. Forehead and lores white. Crest-feathers filamentous and not acuminate. Mantle pale grey. Outer web of first primary black nearly to the tip. Below white, tinged pink. Australia and New Zealand.

The Mekran Large Crested Tern.

Thalasseus bergi bakeri Mathews, Birds of Australia, ii, p. 346 (Sept. 1912) (Mekran coast). Sterna bergii. Blanf. & Oates, iv, p. 314 (part.).

Vernacular names. None recorded.

Description. Similar to the preceding but breeding birds are darker and they are also slightly larger and have decidedly stouter bills.

Colours of soft parts as in the other races.

Measurements. Wing 833 (exceptional) to 385 mm.; tail 150 to 205 mm.; tarsus 33 to 35 mm.; culmen 61 to 70 mm.

Distribution. Sind, Mekran coast and Persian Gulf.

Nidification. This Crested Tern breeds from May to July on the islands of the Persian Gulf and off the Mekran coast. In some of these islands the colonies number thousands, in others two or three hundred only. Eggs and nests resemble those of the preceding bird. One hundred average 67.5 x 42.5 mm.

There are also breeding-places of this species of Tern off the northern coast of the Bay of Bengal from the Sunderbands to the coast of Akyab, but these all probably belong to the smaller race, edwardsi.

Habits. Similar to those of the preceding race. More material for comparison of the races is badly wanted by the British Museum, especially from the East Indian and Burmese coasts.

The Chinese Large Crested Tern.

Sterna cristata Stephens, Gen. Zool. (Shaw), xiit,pt. 1, p. 146 (1826) (China). Sterna bergii. Blanf. & Oates, iv, p. 314 (part,).

Vernacular names. None recorded.

Description. A small race very similar to T. b. edwardsi but paler above.

Colours of soft parts as in the other races.

Measurements. Wing 322 to 357 mm.; culmen 59 to 67 mm.

Distribution. Coasts of China, Indo-Chinese countries and the islands of the Mergui Peninsula.

It is with some hesitation I admit this race to our Avifauna but two specimens from Southern Tenasserim, possibly casual visitors only, seem nearer to it than to edwardsi, which is the breeding bird in that locality.

Nidification. In 1896 I received from an island in the Mergui Peninsula skins and eggs of a Crested Tern which were possibly of this race, whilst "Williamson and Herbert took eggs on small islands in the Gulf of Siam. They found single eggs laid on the bare rock with no nest. Thirty-two eggs average only 58.7 X 41.8 mm.; much smaller than the eggs of other races.

Habits. Those of the species.

* Non-breeding birds occasionally wander great distances and make measurements sometimes unreliable. Thus a dark bird with a wing of 385 mm. waft obtained off the Malay coast.. Another difficulty is the large number of unsexed birds in the British Museum collection. Measurements of sexed breeding birds make the differences of the various races much more distinct.

The Ceylon Large Crested Tern.

Thalasseus bergii edwardsi Mathews, Birds of Australia, ii, p. 347 (Sept. 1912) (Ceylon). Sterna bergii. Blanf. & Oates, iv, p. 314 (part.).

Vernacular names. Muhudu lihiniya (Cing.): Kadal-kuravi (Tam.).

Description. In colour as dark as T. b. bakeri but smaller.

Colours of soft parts as in the other races.

Measurements . Wing 300 to 355 mm.; culmen 58 to 66 mm.

Distribution. Ceylon and the Laccadives, Assam, Bengal, the Burmese coasts to the Mergui Archipelago.

Nidification. This race of the Crested Tern breeds on the islands off the coast of Ceylon, making no nest but laying its eggs either in hollows in the sand or on the bare rock. Only one egg is kid, just like those of the other races, except that the deep pink and salmon type is unusual, many of the eggs being quite white in ground and ranging from this to pale cream, buff or pink. Twenty eggs average 60.0 x 42.4 mm.: maxima 64.2 x 44.2 mm.; minima 54.9 x 40.3 mm.

Parker found them breeding on Adam's Bridge in June but Wait and Phillips obtained eggs on the 30th of April and 5th of May respectively.

Habits. A. resident bird with the usual habits of the species.

The Red Sea Large Crested Tern.

Sterna velox Cretzsch., Atlas Reise nord Afr., ii, tab. xiii, p. 21 (Red Sea). Sterna bergii. Blanf. & Oates, iii, p. 314.

Vernacular names. None recorded.

Description. - Breeding plumage. Upper part of head, from fore-crown to nape, including well-developed crest velvety-black ; forehead, hind-neck and edge of wing white; upper plumage grey, tinged ashy; primaries edged black on the outer webs, blackish on the inner webs with broad, white wedge-shaped patch on the outer feathers gradually lessening inwardly and disappearing on the innermost; secondaries white on the inner webs and tipped white ; outer tail-feathers with white lores and dark grey tips; rest of plumage white.

Colours of soft parts. Iris dark brown; bill lemon-yellow; legs and feet black, the soles yellowish.

Measurements. Wing 340 to 376 mm.: tail 165 to 205 mm.; tarsus about 34 to 35 mm.; culmen 60 to 71 mm.

In Winter the head is white, the feathers with broad black centres, increasing in size on the nape, whilst the crest-feathers are all black.

Young birds have the upper parts dull brownish-grey, edged brown on the inner webs and buffish on the outer webs.

Distribution. Red Sea and East African coast. One or two specimens from Sind seem to belong to this paler race aud have small bills. It is only possible to discriminate between these two races if authentic bleeding birds are examined.

Nidification. This fine Tern breeds in great numbers on many of the islands in the Red Sea, off the coast of the whole of Somaliland and probably a good deal farther South. The eggs, which number one to three, varying in the different colonies, are laid in depressions scratched in the sand by the parent birds without any kind of shelter from sun or rain. The breeding-season is from June to August and if the birds leave the eggs exposed to the sun for too long they are rendered infertile and, indeed, sometimes half-cooked. The eggs of this Tern and of the Lesser Crested Tern are probably the most beautiful of all seabirds* eggs, even exceeding in variety of colour and richness of tint the eggs of the Sandwich Tern. The ground-colour varies from pure white through pale cream, salmon, buff or pink to deep warm salmon and buff and even to rich brick-red. The markings are of two kinds: either large bold blotchings of red-brown, purple-brown or blackish-brown, in some being smaller and more speckly ; the second type has the same coloured marks in large scrolls and scriggly lines all over the egg. Intermediate forms occur but are rare and in fewer eggs still the markings form clouds and blurred blotches. Secondary markings are few or obsolete and are of grey and pale lavender. One hundred eggs average 62.1 x 43.0 mm.: maxima 66.3 x 44.5 and 63.5 x 45.1 mm.; minima 58.1 X 43.0 and 59.2 x 39.8 mm.

Habits. The Terns of this genus are essentially Sea-Terns and keep exclusively to the sea coast, feeding on small fish, mollusca and, it is said, water insects. Fish they take on the wing, dropping like an arrow into the sea and often wholly submerging themselves in their attempts to seise their prey. Like all the Terns which feed thus, they fly along with bill held straight down as they watch for their dinner ; for a moment or two they hover with widespread tail and beating wings and then with a demi-somersault plunge down to the water. Their cry is a hoarse and loud edition of that of the Common Tern, very much like that of the Sandwich Tern but still louder and of a deeper tone.

* Mathews, * Birds of Australia,' ii, p. 340 et seq. (Sept. 1012).

(Sterna bergii Lichtenstein, Verz. Doubl. Zool. Mus. Berlin, p. 80, 1823: Cape of Good Hope.)

Thalasseus bergii bakeri Mathews, Birds Austral., vol. ii, p. 346, 1912: Mekran Coast.

Sterna cristata Stephens in Shaw's Gen. Zool., vol. xiii, pt. 1, p. 146, 1826: China.

Thalasseus bergii edwardsi Mathews, Birds Austral., vol. ii, p. 347, 1912: Ceylon.

Sterna velox Cretzsch., Atlas Reise nord. Afr., vol. ii, tab. xiii, p. 21, 1826: Red Sea.