Wednesday, 31 October 2018
31-10-2018 ALBUFERA, VALENCIA - GREAT EGRET (Ardea alba)
The great egret, known scientifically as Ardea alba, is a majestic bird with a stately bearing and an impressive wingspan. This large egret is adorned with all-white plumage and can stand up to a meter tall. It is a cosmopolitan species, found across temperate and tropical regions worldwide.
To identify the great egret, look for its yellow bill and contrasting black legs and feet, which may vary slightly during the breeding season. During this time, the bill may darken, and the lower legs may lighten. The great egret also sports ornamental feathers on its back when in breeding plumage. Both sexes appear identical, and juveniles resemble nonbreeding adults. The great egret can be distinguished from the intermediate egret by the gape of its bill, which extends well beyond the back of the eye.
The great egret favors habitats close to water, such as large lakes with reed beds and other extensive wetlands. It nests in colonies, often at heights of 10 to 40 feet within trees.
This bird has a vast range, occurring worldwide in suitable habitats. It is particularly common across the Sun Belt of the United States and throughout the Neotropics.
The great egret is known for its slow, graceful flight with its neck retracted, a characteristic of herons and bitterns. It walks with its neck extended and wings held close. Generally silent, it may emit a low, hoarse croak when disturbed and a louder croaking at breeding colonies.
The great egret's vocalizations include a low croak when disturbed and various croaking and squawking sounds during the breeding season.
Breeding begins at 2-3 years of age with monogamous pairings. The male initiates nest building to attract a female. The nest is a sizable structure of sticks, lined with plant material. The species lays up to six bluish-green eggs, with both parents sharing incubation duties over 23-26 days. The young are fed by regurgitation and can fly within 6-7 weeks.
The great egret can be confused with the snowy egret, which is smaller with a black bill and yellow feet. In North America, it may also be mistaken for the white morph of the great blue heron, which is larger with a thicker bill.
The great egret's diet consists of fish, frogs, small mammals, reptiles, crustaceans, and insects. It typically forages in shallow water, standing still or slowly stalking its prey before impaling it with its sharp bill.
The great egret is listed as Least Concern by the IUCN. It has recovered from historical threats such as plume hunting and has adapted well to human presence. It is partially migratory, with some populations moving south during colder winters. The species is a symbol of conservation success and represents the National Audubon Society.
31-10-2018 ALBUFERA, VALENCIA - GREY HERON (Ardea cinerea)
The Grey heron (Ardea cinerea) is a large long-legged wading bird of the heron native to Europe and Asia and also parts of Africa. It lives in wetland areas and feeds on various aquatic creatures which it catches after standing stationary beside or in the water.
The plumage of the Grey heron is largely ashy-grey above, and greyish-white below with some black on the flanks. Adults have a head and neck white with a broad black supercilium that terminates in the slender, dangling crest, and bluish-black streaks on the front of the neck. The scapular feathers are elongated and the feathers at the base of the neck are also somewhat elongated. Immature birds lack the dark stripe on the head and are generally duller in appearance than adults, with a grey head and neck, and a small, dark grey crest. The pinkish-yellow beak is long, straight, and powerful, and is brighter in color in breeding adults. The iris is yellow and the legs are brown and very long.
these birds are resident, but populations from the more northerly parts of Europe migrate southwards; some remain in Central and Southern Europe, and others travel on to Africa south of the Sahara Desert. Grey herons can be found anywhere with suitable watery habitats that can supply their food. Although most common in the lowlands, they also occur in mountain tarns, lakes, reservoirs, large and small rivers, marshes, ponds, ditches, flooded areas, coastal lagoons, estuaries, and seashore. They sometimes forage away from water in the pasture, and can even be found in desert areas, hunting for beetles and lizards.
Grey herons are social birds; they may feed alone or in groups and at night they roost in trees or on cliffs and tend to be gregarious. During the breeding season, they nest in big colonies. Grey herons usually hunt around dawn and dusk but they may also be active at other times of the day. They often perch in trees, but spend much time on the ground, striding about or standing still for long periods with an upright stance, often on a single leg. The main call of Grey herons is a loud croaking "fraaank", but a variety of guttural and raucous noises is heard at the breeding colony. A loud, harsh "schaah" is used by the male in driving other birds from the vicinity of the nest, and a soft "gogogo" expresses anxiety, as when a predator is nearby or a human walks past the colony. The chicks utter loud chattering or ticking noises.
Grey herons are serially monogamous; they form pairs and remain together for only one breeding season, which extends from early February until May or early June. These birds breed in colonies known as heronries, usually in high trees close to lakes, the seashore, or other wetlands. Courtship involves the male calling from his chosen nesting site and on the arrival of the female, both birds participate in stretching and snapping ceremonies. Females lay 3 to 5 eggs and both parents incubate them for 25-26 days. Chicks hatch altricial and are fed by both parents, who look after them attentively; one of the adult birds stays at the nest for the first 20 days. The young can fly at about 50 days old, remaining for 10 to 20 more days more at the nest.
Tuesday, 30 October 2018
Sunday, 28 October 2018
Friday, 26 October 2018
Thursday, 25 October 2018
24-10-2018 MUNTANYETA DEL SANS, VALÈNCIA - WHITE WAGTAIL (Motacilla alba)
The White Wagtail (Motacilla alba) is a small, elegant passerine bird, a member of the family Motacillidae, which includes pipits and longclaws. This slender bird measures between 16.5 to 19 cm in length, with East Asian subspecies reaching up to 21 cm. It is characterized by its long, constantly wagging tail, a behavior that has become synonymous with the genus. Weighing an average of 25 g, the White Wagtail can live up to 12 years in the wild.
Adult White Wagtails exhibit a distinctive plumage with a combination of grey, black, and white. The bird's upper parts are generally grey, with a white face, belly, and breast. Males during the breeding season may show a darker back, and the species is known for its sharp, brisk call and more melodious song during courtship.
The White Wagtail is commonly found in open country, often in close proximity to human habitation and water sources. It shows a preference for bare areas which facilitate the sighting and pursuit of prey. This bird has adapted well to urban environments, utilizing paved areas such as parking lots for foraging.
This species has a vast breeding range across Europe, the Asian Palearctic, parts of North Africa, and has a presence in Alaska. It is a migratory bird, with populations moving to Africa and parts of Asia during the winter. In Great Britain and Ireland, the darker subspecies known as the Pied Wagtail is more prevalent.
The White Wagtail is known for its perpetual tail wagging, a behavior that remains somewhat enigmatic but is thought to be a signal of vigilance to predators. It is a monogamous bird that defends its breeding territory with determination.
The call of the White Wagtail is a sharp "chisick," softer than that of the Pied Wagtail. Its song is more structured and is used by males to attract females rather than to mark territory.
White Wagtails are monogamous breeders, with both sexes contributing to nest building. The nest is often placed in crevices or holes near water or in human-made structures. The species lays three to eight cream-colored, speckled eggs, which both parents incubate. Chicks fledge after 12 to 15 days and continue to be fed for a week thereafter.
The Pied Wagtail, particularly the subspecies M. a. yarrellii, is similar but has a darker back and is found in Great Britain and Ireland. Other subspecies vary in wing, back, and head coloration.
The diet of the White Wagtail primarily consists of insects and small invertebrates, including beetles, dragonflies, flies, and crustaceans. It continues to feed on insects even in winter, unlike many other insectivorous birds in temperate climates.
The White Wagtail is classified as Least Concern by the IUCN. Its population is large and stable, and the species has adapted well to human-altered landscapes. However, it faces threats from being kept as pets, used for food, and potentially from climate change affecting migration patterns.
The White Wagtail is the national bird of Latvia and has been depicted on the postage stamps of several countries. It is celebrated in Latvian folk songs and holds a special place in the cultural heritage of the regions it inhabits.
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