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Home , Little egret, Squacco heron

Studies of less familiar 182 Little Stanley Cramp

Exploited for its elegant plumes, the was threatened with extinction in the late 19th century; but public outcry brought protection in time. The Little that now occur annually in spring in Britain and reflect the ' recovery in

he Little Egret garzetta has a gleaming white plumage, decorated T in the breeding adult with long, elaborate plumes on the upper breast, mantle and scapulars, and with two thin crest hanging down the back of its neck (plates 42-45). The bill and legs are black and the feet yellow (black in the East Indies and Australasian races), but in the breeding season the feet change from yellow to orange, and the bare loral area and the ring around the yellow eyes from green-grey to orange. The non-breeding adult has fewer, shorter plumes and no long crest feathers (plate 48); the juvenile lacks both plumes and crest feathers. Litde Egrets are distinctive as well as elegant, unlikely to be confused with any other species in most of the western Palearctic except, momen­ tarily, with Cattle Egrets Bubulcus ibis at a distance, especially when these are in non-breeding plumage, or perhaps with Squacco Ardeola ralloides in flight, when the latter's all-white wings may draw attention away from the tawny-buff bodies. There are, however, rarer possibilities of much greater confusion in some areas. The related Reef E. gularis, normally dark, has a white morph, with similar all-white plumage and plumes, and dark legs with yellow feet, but its bill is thicker and grey-brown or yellow. Little Egrets have a dark morph (plate 46), exceptional in the western Palearctic but regular in East and , which can be even more difficult to tell from the normal dark Reef Herons, except for the thinner black bill and feet of a paler, purer yellow. Lastly, there is the possibility that the closely related E. thula (considered by some to be conspecific) may cross the Atlantic, as the Little Egret has rarely done in the reverse direction. Snowy Egrets (plate 47), though smaller, are indistinguishable in non- breeding plumage, and differ only in having longer crests without the two elongated plumes, and recurved instead of straight scapulars. The Little Egret has a wide distribution in middle and low latitudes, from southwest Europe and North Africa to the Middle East, , China, southeast , the Philippines and East Indies to New Guinea and . It is patchily distributed in Africa south of the Sahara (with the Banc d'Arguin and the Islands as isolated out­ posts) and in Madagascar, but is absent from North and South America. It is found both on the coasts and inland, preferring warm, shallow

206 [Brit. Birds, 70: 2o6-2l

43. Little Egrets Egretta garzetta (foreground and right) and Bubulcus ibis (left) at nests, Spain, May 1956 {Eric Hosking) 44- Little Egrets Egretta garzetta (fore• ground and right) and Cattle Egret Bubulcus ibis (left) at nests, Spain, May 1956 (Eric Hosking)

45. Little Egret Egretta garzetta at in reed-bed, Portugal, May 1973 (K. J. Carlson) Little Egret studies 209 waters, whether lakes, pools, lagoons, gently flowing rivers, streams, rice- fields and other fresh water, or saline and brackish waters in estuaries, saltpans or along the coast. It is usually confined to lowlands, but occurs at up to 2,000 m in Armenia. In such habitats, Little Egrets take a wide variety of food, with , terrestrial and aquatic and small amphib­ ians forming the most important part, though they will also eat small , snakes, lizards, various , snails and . The species chosen vary widely according to season and locality, and vary in size from 1.2 to 15 cm, with a preference for those around 4 cm (Valverde 1955-56, Sterbetz 1961). Little Egrets feed by day and at dawn and dusk, often while wading slowly in shallow water (plate 48), but they can be active, rushing to and fro snapping at their prey, sometimes running with raised wings. In summer they may often be seen feeding also on dry land, when they may attend grazing , though not so frequently as do Cattle Egrets. Voous (i960) suggested that the present discontinuous distribution of the Little Egret has been partly caused by man's activities, in the form of direct persecution and habitat destruction. Indeed, its elaborate plumes were once a threat to its continued existence in some areas. In the latter part of the 19th century, these plumes were used so extensively in the millinery trade as 'aigrettes' that Little Egrets and related species (such as the Great White Egret E. alba, the and the Snowy Egret) were slaughtered in thousands at their breeding colonies and the young left to die. Public reaction against this carnage played a vital part in the growth of the first protection societies in both Europe and North Ameiica, and, after a long and bitter struggle, the plumage trade was gradually brought under control. Its effects on the luckless birds have been most fully studied in the case of the Squacco Heron, where Jozefik (1969-70) showed that the slaughter reached its peak about 1900, but numbers in the west Palearctic continued to fall, mainly due to habitat destruction, until by 1920-40 there were 6,000 pairs in 80 colonies com­ pared with 16,400 pairs in 1,965 colonies before the plumage trade de­ veloped. Since 1940, there has been a slight increase in numbers, despite further habitat loss, to 8,200 pairs in only 71 colonies, though many of these are actively protected in reserves. The general picture is likely to be similar in the case of the Little Egret, but detailed information is much more scanty. In , it became extinct in the last century, but returned to the Camargue in 1931 and has since spread to other areas, reaching 1,815 pairs in 1974 (Brosselin 1975). Similarly, it vanished from Hungary in 1895, returning in about 1928, although its numbers are still small, fluctuating between 150 and 214 pairs during 1959-68 (Sterbetz and Szlivka 1972). It'has nested occasionally in Czechoslovakia in recent years and has increased in Italy. In Romania, despite large decreases in the last 50 years, it is still fairly common, especially in the Danube delta, but the colonies of the Volga delta have had "a more chequered history: after almost complete destruction early this century, they re­ covered markedly under protection (Dementiev and Gladkov 1951), then declined in the lower delta to only nine pairs in 1957 (Lugovoi 210 Little Egret studies 1961). Despite some recovery, the Little Egret remains highly vulnerable to the drainage of wetlands. Although a few Little Egrets winter in the Mediterranean area, those breeding in Europe are basically trans-Saharan migrants, some reaching as far as the equator. Ringing recoveries show that Little Egrets from Russia, Yugoslavia, France and Spain reach West Africa, from Sierra Leone to Nigeria, while Spanish birds have been found in Madeira and the Canary Islands. Some winter in , and they then occur commonly in the Sudan. The return passage begins in March, with colonies in Hungary and the Volga delta being reoccupied from early April. Little Egrets are prone to overshoot in spring, when single ones and even small parties may appear well north of the breeding range; these influxes, sometimes large, are now regular in south Germany, Austria and Switzerland, where birds may stay for several weeks (Bauer and Glutz 1966). In Britain and Ireland, the species was regarded as a rare vagrant before 1950, but has now become a regular spring visitor (over 40% of recent records have been in May) and exceptionally ovei- winters. Little Egrets are colonial nesters in reed-beds, alder thickets, bushes and trees. Colonies may be separate, but more often include other species, such as Plegadis falcinellus, Pygmy Phalacrocorax

46. Little Egret Egretta garzetta: dark morph, which may be confused with normal dark morph of the similar Reef Heron E. gularis, Kenya, June 1976 (J. F. Reynolds) 47- Snowy Egrets Egretta Aula, Trinidad, June 1976 (colour transparency: M. D. )

48. Little Egret Egretta garzetta immediately after swallowing large shellfish, Portugal, November 1969 (M. D. England) 49. Little Egret Egretta garzetta in flight, showing long legs and pale feet, Romania, September 1974 (K. J. Carlson) 50. Little Egrets Egretta garzetta at nest, Spain, May 1956 (Eric Hosking)

51. Little Egret Egretta garzetta regurgitating food for newly-hatched young, Portugal, May 1973 (K. J. Carlson) Little Egret studies 213 pygmeus, Night Heron Nycticorax nycticorax, Cattle Egret and Squacco Heron. In one mixed colony in the Danube delta, the nests were in a tangle of* willows in a large reed-bed, mostly at 2-3 m, and sometimes with those of Pygmy in the same tree (Cramp and Ferguson- Lees 1963). Soon after their arrival at the colony in spring, unpaired males frequent small display territories, where they spend much of the time climbing up and down, uttering loud advertising calls, either a gargling 'la-la-la-la-ah-h-h' or a biief, hollow 'dow', or indulge in twig-shaking with extended necks, while uttering a brief, nasal, chattering call. They also make short display flights, flapping their wings to make a thudding sound, or longer, circling flights of up to 300 m. Females and other males will perch near these displaying males, forming a highly vocal group which may move round the colony. Once the pair is formed, both adults defend the chosen nest site vigorously against their own and other species. The pair display to each other by bill-rattling, a rapid movement of the mandibles, often performed above the mate's back or across its neck, and by short, flapping flights (Blaker 1969). There is usually little display preceding copulation. The nest is built by both sexes, although usually the male brings most of the material while the female builds. The nests, platforms of sticks or reeds, which may be flimsy or quite solid, are built up to 20 m above ground or water, usually not less than 1-2 m apart, with up to ten nests in one tree. The elongated, oval , green-blue in colour, not glossy and soon discoloured during incubation, are usually laid at intervals of 24 hours. Most clutches are of three to five eggs, with up to eight recorded; the mean clutch size in Spain was 4.8 (Valverde 1955-56). Both sexes incubate, starting with the first , for 21-22 days. During incubation, as in the earlier mating phase and later while small young are in the nest, the arrival of an adult at the nest leads to an attractive greeting ceremony (plate 50). The incoming bird utters a 'da-wah' call, its mate reciprocates, assuming the upright-display posture, then both chatter-call. Then, for several seconds, both assume a less intense version of the antagonistic forward-display with neck raised, bill open and all plumes raised, then slowly subside or rattle their bills. When the young hatch, they are clad in white down, with greenish bills and legs. They are fed with regurgitated material by both parents (plate 51). The young will beg with open bills pointing upwards, uttering a 'he-he-he' call, but make no serious attempts to seize the parent's bill. Later, adults regurgitate food into the bottom of the nest. The young leave the nest after about 30 days and perch on nearby branches; they show strong mutual attachment and will co-operate in defence against other wandering young or possible attackers. They fledge 40-45 days after hatching and soon become independent. They rapidly disperse from the colony, more or less at random; these movements are related to feeding conditions (Valverde 1955-56), and last from July to September. Some Spanish juveniles have moved up to 400 km north at this time, while Camargue juveniles have been recovered in Iberia and Italy. Two Spanish-ringed nestlings were recovered across the Atlantic, one in 214 Little Egret studies Trinidad in January and the other in Martinique in October. In late August and early September, these early autumn movements of juveniles merge gradually into true autumn migration, involving adults as well, which may last until November or later, especially in the Caspian region. References BAUER, K. M., and GLUTZ VON BLOTZHEIM, U. N. 1966. Handbuch der Vbgel Mitteleuropas. vol. 1. Frankfurt am Main. BLAKER, D. 1969. Behaviour of the Egretta garzetta and E. intermedia. Ostrich 40: 150-155. BROSSELIN, M. 1975. Herons Arboricoles de France, vol. 1 Paris. CRAMP, S., and FERGUSON-LEES, I. J. 1963. The birds of the Danube delta and their conservation. Brit. Birds 56: 323-339. DEMENTIEV, G. P., and GLADKOV, N. A. 1951. Ptitsy Sovieskogo Soyuza. vol. 1. Moscow. JOZEFIK, M. 1969-70. Studies on the Squacco Heron, Ardeola ralloides (Scop.). Acta orn. Warsz. n: 103-262; 12: 57-102, 393-504. LUGOVOI, A. E. 1961. Dynamics of distribution of colonial birds at the lower zone of the Volga Delta during the breeding season. Trudy Astrakh. zapov. 5: 211-219. STERBETZ, I. 1961. Der Seidenreiher. Wittenberg Lutherstadt. and SZLIVKA, L. 1972. Capljicabela, Egretta g. garzetta L., u Karpatskom bazenu u periodu 1959-1968. godine. Larus 24: 141-148. VALVERDE, J. A. 1955-56. Essai sur L'Aigrette Garzette {Egretta g. garzetta) en France. Alauda 23: 145-171, 254-279; 24: 1-36. Voous, K. H. i960. Atlas of European Birds. London.

Stanley Cramp, 32 Queen Court, London WCIN 3BB