Birds of Prey in Belarus. Little egret Middle egret

RWD-14 Czapla RWD-14 "Heron" Close reconnaissance, spotter and communications aircraft. Single-engine parasol monoplane of mixed design with fixed landing gear. Designed in research center"Dosviadzalne Warshtaty Lotnichi" (DWL) under the leadership of S. Rogalsky and

Appearance and behavior. The heron is of medium size, noticeably smaller, but larger and. Body length 55–65 cm, weight 350–550 grams, wingspan 88–95 cm. It has a very graceful physique and a small head with a long and thin beak. Birds in breeding attire, in addition to a lush “cape” of openwork aigrete feathers on their backs, have a long “pendant” in the lower part of the neck and a crest of several (usually two) long narrow feathers, which never happens in a great white heron.

In autumn and winter, egrets, pendant and crest are not expressed. The most reliable hallmark can be seen when the little egret shows its legs: the yellow fingers contrast sharply with the black tarsus. Likes to stay in small groups in shallow water, quite mobile and not particularly cautious. These herons often fly in flocks, rarely lining up in a wedge or line, usually flying in a "bunch" like starlings. Active mainly during the day.

Description. The plumage is completely white in birds of any age and in any season. The beak and legs are black, the toes in breeding plumage are bright yellow, in winter they are dull and dirty yellow, but they always differ in color from the tarsus, even in young birds, in which they are rather greenish. The beak is black in all seasons (in young birds it is dark with a yellowish base of the mandible). The bare skin around the eyes and the lore are bluish in autumn and winter and yellow (to orange) in the mating season. In young birds, these areas are grayish. The eyes are yellow at any age.

Distribution, status. The breeding range includes the southern regions of Europe, Africa, southern Asia and Australia. AT European Russia found in the south, along the coasts of the Black, Azov and Caspian Seas and in the lower reaches of the rivers flowing into them. In most of the places it inhabits it is quite common, in some it is the most conspicuous and numerous of the herons. Migrant, the nearest wintering grounds are in Transcaucasia.

Lifestyle. It nests in colonies, usually on trees, much less often in reed beds, along the banks of various water bodies, often together with other near-water birds. On trees, nests built from thin long dry rods are fixed on horizontal branches, sometimes very far from the trunk. The shape of the nest, like that of other types of herons, resembles an inverted cone with translucent walls.

The nest is built by both partners, and the male brings the material, and the female puts it in the nest and guards the building from other herons nesting in the neighborhood. Clutch contains 4-5 greenish-blue eggs. The clutch is incubated mainly by the female for 25 days. Fledgling chicks move to the branches of the tree, where they spend most day; when parents appear, the chicks rush to their nest, where they receive food.

General characteristics and field signs

A slender heron of medium size (body length about 70 cm) and a typical "heron" build. The plumage is loose, pure white in color. In breeding attire, long feathers (egrets) stand out on the back, protruding 10-15 cm beyond the top of the tail. On the underside of the neck and goiter, there are feathers up to 20 cm long, forming a “mane”. There are no elongated feathers on the head. Characteristic seasonal changes beak colours.

Larger than the little and yellow-billed herons, but smaller than the southern and great egrets. In terms of flight and the nature of movement on the ground, it also occupies an intermediate position between relatively small (little, yellow-billed) and large (great and southern) egrets. In addition, it differs from the yellow-billed and little egrets by its monophonic fingers with a tarsus (black, not yellow), and in breeding plumage - by the absence of elongated feathers on the back of the head and relatively longer egrets that extend far beyond the top of the tail. From southern and great egrets, in addition to smaller sizes, it differs in entirely black legs, high at the base and a shortened beak, and in breeding plumage - in the presence of long feathers on the goiter. On the close range it is noticeable that in the middle egret the corner of the mouth ends just below the eye, and does not go much further, as in the great egret (Cramp, 1977; Beaman and Madge, 1998).

The flight is calm and straight, with deep beats of broad wings. Takes off easily and quickly. During the flight, the legs are extended beyond the top of the tail, and the neck is bent in a vertical plane and drawn into the shoulders. Inhabits wetlands. Settles together with other types of herons. During the period of wandering and migration, it prefers to stay in groups, often uniting with other species of white herons, forming sparse clusters for feeding. immature birds in summer period lead a nomadic lifestyle, meeting far beyond the nesting range.

Description

Coloring. There is no sexual dimorphism in coloration, however, males have slightly longer feathers than females.

Adult male and female. The plumage is white. Legs entirely black; the bare skin of the “face” is yellowish-green during the nesting period, and yellow the rest of the time. The iris is pale yellow. In breeding plumage, the beak is black with a yellow base, the rest of the time it is yellow with a black tip. AT mating season there are decorating feathers on the goiter and back (egrets).

First down outfit. The fluff is white. The beak is flesh-pink with a black tip.

The second down outfit. The fluff is white. The beak is yellowish with a black tip.

Nest outfit. The plumage is white. The beak is yellow with a black tip. The bare skin at the corners of the bill, on the bridle and around the eye is yellowish. Legs are blackish.

First year outfit. The plumage is white. There are no decorative feathers on the back and lower neck. The beak is yellow with a dark tip. The bare skin on the frenulum and around the eye is yellowish. Legs are black.

Structure and dimensions

Slender bird. The neck is long and thin, but looks noticeably thicker and shorter than that of other white herons, and the legs are long. The beak is relatively somewhat shorter and higher than that of other egrets found within Russia.

Dimensions (mm). Male wing length 290-325, tarsus 110-130, beak 70-96 (Stepanyan, 2003). The bird caught in Primorye (sex not established) had a wing length of 307, a tarsus length of 101, and a beak length of 96 (Buturlin and Dementiev, 1935). Sizes of males and females from China: wing length 280-330, tarsus length 98-100, beak length 67.5-100 (Ivanov, 1961). Individuals from Sev. Korea: female - wing 313, tarsus 114, tail 122, beak 74; bird of indeterminate sex - wing 308, tarsus 111, tail 118, beak 71 (Tomek, 1999). Birds taken on Sakhalin: males (n = 2) - wing 303 and 313, tarsus 117-118, beak 76 and 76.5 (Takahashi, 1937); female - wing 290, tarsus 105, tail 123, beak 71 (Nechaev, 1991).

Birds caught in Primorsky Krai: males (n = 2) - wing length 300 and 300, tarsus length 105 and 115, beak length 75 and 75; females (n = 3) - wing length 295, 300 and 300, tarsus length 100, 103 and 105, beak length 70, 74 and 75; birds whose sex is unknown (n = 3) - wing length 290, 295 and 300, tarsus length 103, 108 and 110, beak length 70.71 and 72 (col. BPI FEB RAS and FEGU, Vladivostok).

Sizes of males and females (mm) of subspecies E. i. intermedia (Cramp, 1977): average wing length 299 mm (275-327, n = 13), tail length - 118 (103-135, n = 7), beak length - 72.8 (66-76, n = 14), tarsus length - 106 (93-111, n = 7).

Weight of birds from China: males (n = 2) - 470 g and 642 g, female - 600 g, bird, the sex of which has not been established - 700 g (Ivanov, 1961). The female obtained in the South. Sakhalin, weighed 458 g (Nechaev, 1991).

Moult

The full annual molt of adult birds runs from July to November. Partial prenuptial molting occurs during wintering. Young birds in nesting plumage begin to change small feathers in August, continue in autumn and finish during wintering; in their second year of life, they undergo a complete annual molt.

Two birds caught in the hall area. Olga (Primorsky Territory) on May 20, 1980, were in breeding attire, however, the beak of the male was yellow with a dark top, and that of the female was black with a yellow base. Of the three birds caught on the lake. Khanka, one individual from June 30, 1978 had no traces of molting; in specimen from July 15, 1977, the molting of small plumage began; an adult female, taken on July 25, 1980, was in the midst of a complete molt (about a third of the flight and tail feathers were lost or growing, an intensive molt of small plumage occurred).

Subspecies taxonomy

polytypical view, geographical variability which manifests itself in overall dimensions and varying the color of non-feathered parts of the body (beak, legs, bridle). Three subspecies, of which only the nominative one is known within Russia.

1.Egretta intermedia intermedia.

Ardea intermedia Wagler, 1829, Isis, stb. 659, Java.

The general size is somewhat larger, and the color of the unfeathered part of the lower leg is black, and not yellowish-orange, as in the other two subspecies. In the non-breeding season, the beak is yellow with a black tip. Inhabits South, South-East. and, in part, Vost. Asia.

Subspecies E. and plumifera (Gould, 1848) (2) distributed in Australia, on about. New Guinea and adjacent islands, is smaller in size, and in color of the non-feathered parts of the body approaches the African race. Subspecies E. and brachyrhyncha (A.E. Brehm, 1854) (3) distributed in the Center, and South. Africa, it approaches the nominate subspecies in size, but has a yellowish-orange bill and an unfeathered part of the tarsus.

Notes on systematics

The egret is sometimes placed in the monotypic genus Mesophoyx Sharpe, 1894 (more often treated as a subgenus of the genus Egretta) or placed in the genus Casmerodius Gloger, 1842, together with the great egret. DNA hybridization studies have shown that the egret and great egret are more closely related to the genus Ardea than to Egretta (Sheldon, 1987). In this way, systematic position of the middle egret requires further study and clarification.

Spreading

Nesting area. Center, and South. Africa, Sri Lanka, Burma, Indonesia, China, Japan, Korean Peninsula, Moluccas, Sev. and Vost. Australia (Spangenberg, 1951; Stepanyan, 2003; Vaurie, 1965; Dickinson, 2003; etc.). Egrets of the nominative subspecies breed in the central and southern regions of China, on the islands of Taiwan and Hainan (Mackinnon and Phillipps, 2000), in Hong Kong (Carey et al., 2001), and in the central and southern regions of the Korea Peninsula (Won Pyong-oh, 1996; Tomek, 1999), in Japan - on the islands of Honshu, Shikoku, Kyushu and Sado (Check-list of Japanese birds, 2000), as well as in India and Sri Lanka (Fig. 59).

Figure 59.
a - breeding area, b - established isolated nesting sites, c - wintering areas of northern populations. Subspecies: 1 - Egretta i. intermedia, 2 - E. i. plumifera, 3 - E. i. brachyrhyncha.

On South Far East Russian nesting is registered on the lake. Khanka (Polivanova and Glushchenko, 1977; Glushchenko and Mrikot, 2000) and on about. Shikotan, Kuril Islands (Dinets, 1996). An attempt at nesting was observed in the area of ​​Olga Bay, Primorsky Krai (Labzyuk, 1981). In addition, nesting is expected in the extreme southwest of Primorye (Litvinenko, Shibaev, 1999) (Fig. 60).

Figure 60.
a - the established nesting site, b - the area of ​​​​meeting birds during seasonal migrations and summer migrations, c - the proposed place of nesting, d - vagrants.

wintering

Birds of the nominative subspecies winter in the South-East. Asia: in the southern regions of China, on the islands of Taiwan and Hainan (Cheng Tso-Hsin, 1987; Mackinnon, Phillipps, 2000), Philippines, Kalimantan, Indonesia (Vaurie, 1965), Vietnam (Wo Kwi, 1983), Thailand (Lekagul, Round, 1991), in the southern regions of Japan (Kyushu Island and the islands located to the south) (Check-ist of Japanese birds, 2000), Hong Kong (Carey et al., 2001).

The first flights to the territory of Primorsky Krai were registered at the beginning of the 20th century (Buturlin, Dementiev, 1935; Belopolsky, 1955). Since the 1960s they became more frequent and became regular (Litvinenko, Shibaev, 1965; Labzyuk et al., 1971; Elsukov, 1974; Glushchenko, 1981; Labzyuk, 1981, 1990). Flights have been recorded in the Lower Amur Region (Babenko, 2000), Sakhalin (Nechaev, 19916), Moneron (Nechaev, 1975), Yuzh. Kuril Islands: Kunashir (Nechaev, 1969) and Shikotan (Dykhan, 1990) and Kamchatka (Artyukhin et al., 2000). In the northern part of Japan, flights to about. Hokkaido (Check-list of Japanese birds, 2000).

Migrations

In Yuzh. Primorye spring migrations occur at the end of April and in May. The earliest appearance was recorded on April 14, 1993 in the extreme south of Primorye at the mouth of the river. Tumannaya (data from Yu. N. Glushchenko), April 26, 2004 in the vicinity of Ussuriysk (Glushchenko et al. Khanka (Glushchenko et al., 2006) and April 27, 1979 in the hall. Olga (Labzyuk, 1981). Post-nesting migrations on the lake. Khanka occurs in August, and the latest reliable record in autumn was recorded on September 17, 1973. In the vicinity of Vladivostok (the mouth of the Shmitovka River), one individual was observed on September 16, 2007 (data from Yu. N. Glushchenko). On about. Shikotan of two birds was observed on October 16, 1986 (Dykhan, 1990).

habitat

On Khanka, two colonies in which medium egrets nested were located in the estuary part of the river. Ilistaya in a strip of flooded willows surrounded by a lake-marsh massif. Feeding places here are damp meadows, grassy swamps, shallow lakes and rice fields. On about. Shikotan birds nested in the swampy floodplain of the stream, in reed beds with curtains of Kuril bamboo and groups of trees (Dinets, 1996). During the period of seasonal migrations and summer migrations, middle egrets are found along the shores of lakes, rivers and reservoirs, in rice fields, wet meadows and grassy swamps, both in the interior and on the coast.

In China, the Korean Peninsula, and Japan, egrets inhabit grassy swamps, wet grasslands, marshes, mud flats, and rice fields (A field guide to the birds of Asia,

1993). In Japan, they build nests in pine trees and bamboo thickets (Jahn, 1942), on the Korean Peninsula - in trees surrounding rice fields (Gore and Won Pyong-oh, 1971).

population

On the lake Khanka nests irregularly and with variable numbers. For the first time, two nests were discovered in the estuary part of the river. Ilistaya in 1971 (Polivanova and Glushchenko, 1977). In 1973-1980. the species has been recorded almost every year in summer time in the southern and eastern regions of the Khanka lowland, and in 1976-1977. juveniles were noted, which suggests their irregular nesting in this period (Glushchenko, 1981). In 1999-2002 egrets were again found breeding in the same colony, but their numbers, determined in 1999 and 2000, respectively, in 20-30 and 30-40 nesting pairs (Glushchenko, Mrikot, 2000), turned out to be overestimated. In reality, from 7 to 10 pairs could nest here (Glushchenko et al., 2003). In 2000, 8 pairs nested, and three examined nests contained 1,3 and 4 eggs. In 2002, the species was not found here at all, and in June 2003, from 1 to 3 birds were observed in one of the subcolonies of the river delta. Muddy. Singles were also seen feeding in the meadows around the village. Sivakovka (Glushchenko et al., 2003).

On the coast of the hall. Olga (Primorsky Territory) at the mouth of the river. Avvakumovka marked an unsuccessful nesting attempt: the birds began to build a nest, but later it turned out to be abandoned (Labzyuk, 1981). In addition to the breeding population in the southern and eastern regions of Primorsky Krai, in warm time years (mainly from May to July) we regularly met individual single birds and their groups, numbering up to 10 or more birds (Litvinenko, Shibaev, 1965, 1999; Labzyuk et al., 1971; Elsukov, 1974; Voloshina et al., 1999; Labzyuk, 1981, 1990; Glushchenko and Nazarov, orig.). On about. Shikotan in 1988 found a nest with two chicks (Dinets, 1996).

In Japan, the middle egret is few in summer and few in winter in the far south (A field guide to the birds of Japan, 1982). In China this normal view(Mackinnon, Phillipps, 2000); in Hong Kong, common in both summer and winter (Carey et al., 2001); all in. Korea - rare on nesting (Toshek, 1999), and in South. Korea - few in the breeding season (Won Pyong-oh, 1996).

reproduction

Daily activity, behavior

Leads a daily lifestyle. Herons usually feed alone, but sometimes they can gather in flocks of up to tens or even hundreds of birds (Martinez-Vilalta and Mods, 1992). The behavior of the species on the territory of Russia has not been studied.

Food

The main food objects are aquatic and terrestrial invertebrates (molluscs, spiders, insects and their larvae) and vertebrates (fish, amphibians). The stomach of a bird caught on about. Sakhalin on May 26, 1974, contained remains of aquatic insect larvae (Nechaev, 1991). In the stomach of a bird caught on June 30, 1978 on the lake. Khanka, turned out to be a rotan firebrand (.Perccottus glenii) and three dragonfly larvae, and in the stomach of an individual caught in the same place on July 25, 1980, three swimmer larvae, a spider and the remains of insect chitin were found (Glushchenko, orig.).

Enemies, adverse factors

In a colony on the coast of the lake. Khanka herons are experiencing powerful pressure from the main competitor - great cormorant. Other essential negative factor here - high level disturbance from people and livestock. It is especially large in dry years, when the marshy lowland becomes easily accessible (Gusakov, Vinogradov, 1998). Catastrophic consequences for nesting on the lake. Khanka birds may have the destruction of willow thickets by fires at the location of the colony during dry weather (Glushchenko, 2005).

In Japan, the middle egret was abundant in the past, but habitat pollution and disturbance of birds in the colonies has led to a significant decline in numbers since the 1960s. (Martinez-Vilalta and Motis, 1992).

Economic importance, protection

How very rare view economic importance does not have. Listed in the Red Book Russian Federation(2001) and the Red Book of Primorsky Krai (2005). Location of the colony on the lake. Khanka is part of the protected zone of the Khanka state reserve. It is recommended to increase the area of ​​this reserve by including the territory of the specified colony in its composition.

Middle Egret
Egretta intermedia
Order Ciconiiformes - Ciconiiformes
Family Herons - Ardeidae

Habitat
A rare, irregularly nesting species, the northern border of the range passes on the territory of Russia.
Wing length 250 mm.

Spreading. In Russia, the nesting of the middle white heron is established on the lake. Khanka (1). In all likelihood, it breeds in other places of Southern Primorye, in particular, in the vicinity of Olga Bay, where on May 12, 1976, a pair of herons building a nest was found (2). In addition, in July, birds were encountered on about. Kunashir (Southern Kuril Islands), where they apparently bred (3). In the spring-summer period, egrets were regularly observed (or caught) in the following places in the south of the Far East of the USSR: in the Khanka lowland (4), in the Lazovsky Reserve (5, 6), in the vicinity of Olga Bay (2), near the village of Terney and the mouth of the Samarga (7), in the Gulf of Peter the Great on the islands of Bolshoy Pelis and Popov (5, 8), in the southern regions of about. Sakhalin (9). Outside of Russia, the breeding range covers areas of Asia from Northern Japan west to Pakistan, as well as South Africa north to the border of the Sahara and Australia (10).
It nests in water bodies with dense thickets of reeds, shrubs and woody vegetation, in mixed colonies of other species of storks.

Number. On the lake Khanka at the mouth of the river. Istyoy in 1971 found 2 nests in one of the colonies of gray, red and great egrets. During the period of migration and nomadism, the average egrets stay alone, in pairs, or form flocks of 3-10, rarely 20-25 birds.

limiting factors. The low abundance of the species is explained by its habitat on the periphery of the range, as well as the lack of places suitable for nesting, which arose as a result of human changes in the habitat of birds.

Security measures. It is necessary to protect birds during migration and nesting periods.

Class - Birds / Subclass - New-palatine / Superorder - Storks

History of study

The middle egret (lat. Egretta intermedia) is a species of birds of the heron family.

Spreading

Mainly found from eastern Africa along tropical zone South Asia and to Australia.

Appearance

Heron of medium size.

As a rule, males are somewhat larger than females. The plumage is completely white. The beak is long, straight, colored in yellow. Paws and fingers are long, dark gray. The neck is long, S-shaped.

reproduction

It usually nests in colonies with other herons, often on platforms made from piles of tree branches and shrubs. The female lays 2-5 eggs.

Lifestyle

Herons inhabit the coasts and shallow waters of fresh and brackish waters. On Shikotan Island, the birds nested in a swampy stream valley overgrown with reeds and Kuril bamboo with separate groups of trees. Spring migrations in April - May, autumn - in September. The nest, found on the island of Shikotan, was placed in a fork in a willow trunk, 5 m from the ground. Construction material: willow branches, Kuril bamboo stems and dry grass. There were 2 chicks in the nest on July 12 and 13. The lifestyle has not been studied. The main food is fish and aquatic insects.

Food

It searches for food in flooded fields, feeds slowly wandering in shallow water. Sometimes it looks out for prey from the branches of low trees. Feeds on frogs, crustaceans and insects.

population

At a low level. One pair of birds nested on Shikotan. On Sakhalin, during the period of migrations and summer migrations, solitary birds were most often recorded.

Middle Egret and Human

Hunting for herons is prohibited. It is important to conserve wetlands, eliminate disturbance, limit the number of crows in nesting areas of this species, and protect birds in nesting areas.