admin on September 30th, 2008

Main features: Small (40-46cm); greenish-grey; neck short; black crown with long black crest;
adult little heron
underparts paler grey; bill black; legs and toes pale yellow/ orange; facial skin greenish. Genders look alike.

Juvenile: Generally duller; upperparts dark brown; white spots on wings; throat, neck and breast white streaked brown; legs dull green.

In flight: Wings appear all dark; toes project well beyond tail.

Call:
A quiet bird. Its call described as a harsh single ke-yow or chauk when flushed into flight; a raspy kitch-itch-itch; a loud kweak..kee-kee-kee.

Little Herons are often encountered at Sungei Buloh Nature Park, hunched into a compact egg-shape on a branch over the water, motionless but intently looking out for prey. Clothed in their camouflaging plumage, the less observant visitor often overlooks them.

Little Herons eat mainly small fish and crustacea (especially crabs). They also take amphibians and insects and any other edible titbits, including small mammals.

Little Herons use a wide variety of hunting techniques, but usually hunt from cover and rarely forage on the open mudflats.

Often, they perch-and-wait on a branch or root over the water, tucking in their necks and crouching in a low forward position over the water. They may flick their crests up and down as they wait. Little Herons may also jump, plunge or swim after their prey. Or they may use their feet to stir up or rake the surface for titbits. They may even dive into the water.

But more impressively, they may bait fish and other prey, e.g., by dropping a leaf onto the surface. Unlike other herons, Little Herons are not deterred by the rising tide as they are small enough to perch on overhanging branches, though often precariously.

Both adults and young birds have a partial web between the middle and outer toes, which may allow them to swim. Nestlings that fall into the water paddle efficiently to safety. And adult birds paddle back after plunging into water after prey.

These solitary birds usually hunt and roost alone and are highly territorial. But in good feeding areas, several of them may be spaced out at regular intervals. Little Herons prefer to hunt during the early morning and late evening, in shallow waters lined with vegetation which provide good perches and hiding places: mainly mangroves, estuaries, coral reefs and rocky coasts. They may also be found, less commonly and in smaller numbers, in freshwater wetlands such as swamps, streams, canals, reservoirs, and even parks and gardens.

Breeding: In Singapore, Little Herons appear to breed year-round. Courtship displays involve crest raising, neck fluffing with aerial displays, circle and crooked-neck flights and snap displays. This is accompanied by their harsh rasping courting calls and constant tail flicking. Usually, the male performs the displays.

Little Herons usually nest alone, but loose colonies of up to 10 nesting pairs have been encountered, sometimes several nests to one tree. They prefer to nest in mangroves, in trees or in bushes, often over water. They do not appear to nest further than 3 km from the coast. They build flimsy platform nests out of twigs about 30 cm wide and 5cm deep. Nests are built at 2-10 m up. In Sungei Buloh, nests were first recorded in February 2000, made in the mangrove tree, Blind Your Eye (Excoecaria allgalocha) about 5m from the ground.

2-7, usually 5-4, pale greenish-blue eggs are laid. Both parents incubate. Hatchlings are covered in yellow down and emerge at the same time. Both parents feed and raise the young. The young remain in the nest until they fledge. But if disturbed, they will scramble out of the nest and cling to branches to make it more difficult for predators to pick them off.

Migration: Little Herons are generally resident in their range, but those that breed far north in East Asia (A. s. amurensis) do migrate south. These rare visitors to Singapore are slightly larger and usually travel at night.

Status and threats: Little Herons do not appear to be under serious threat as they are still very widespread and found even on oceanic islands. But like other herons, they are affected by habitat destruction and pollution of their environment. In the past they were hunted for food although they apparently only make “tolerable eating”.

Source: http://www.naturia.per.sg/buloh/birds/Butorides_striatus.htm

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