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Showing posts with label BARE THROATED TIGER HERON (Tigrisoma mexicanum). Show all posts
Showing posts with label BARE THROATED TIGER HERON (Tigrisoma mexicanum). Show all posts

Wednesday, 31 January 2018

28-3-2017 TARCOLES RIVER COSTA RICA - BARE THROATED TIGER HERON (Tigrisoma mexicanum)


The bare-throated tiger heron (Tigrisoma mexicanum) is a wading bird of the heron family, Ardeidae, found from Mexico to northwestern Colombia, with one recorded sighting from the United States in Hidalgo County, Texas. It is 80 cm (31 in) in length and weighs 1,200 g (42 oz).

This large species is found in more open habitats than other Tigrisoma herons, such as river and lake banks. It waits often motionless for suitable prey such as fish, frogs or crabs to come within reach of its long bill.

This is a solitary breeder, not normally found in heron colonies. The nest is a small flattish stick platform in a tree into which 2–3 green-tinged white eggs are laid.

The throat is bare and is greenish-yellow to orange in all plumages. The adult has black crown and light grey sides of the head, the sides of the neck and the upperparts otherwise blackish narrowly barred buff. The median stripe down the fore-neck is white-bordered with black; the remaining underparts are dull cinnamon brown. The juvenile is buff coarsely barred with black, more mottled and vermiculated on wings; the throat, median underparts, and belly are whitish.

The flight is heavy, and the call is a hoarse howk-howk-howk. Males also give a booming hrrrowwr! call, especially at sunset. During emission of the call, the beak opens wide and undulations can be seen along the course of the throat from mid-thorax caudally.

Saturday, 6 January 2018

27-3-2017 VILLA LAPAS, COSTA RICA - BARE THROATED TIGER HERON (Tigrisoma mexicanum)


The Bare-throated Tiger-Heron is a bird of tropical swamps. Along the coast, it is typically a mangrove species. It is found, however, in a variety of coastal and freshwater situations, typically characterized as forest edged aquatic habitats. It feeds in coastal lagoons, mangrove swamps, fresh water marshes, swamps, gallery forests along rivers and streams, and wet meadows. It feeds more in the open and in larger habitats than other tiger herons. It is primarily a coastal species occurring below 1,000 m. It avoids human habitats.

The primary foraging behavior of this cryptic heron is Standing in shallow water or on the edge of the water, with neck stretched out diagonally, waiting motionless for long periods. It also Walks slowly, often in situations away from cover. It is a solitary species, usually foraging alone. However a dozen have been seen in a loose group when food is readily available. It is primarily crepuscular but also partially nocturnal. When disturbed it takes flight and perches in a nearby tree. It eats fish, frogs, crabs, and flies.


The breeding season is variable. In Costa Rica nesting may be year round but peaks at the early rainy season (Styles and Skutch 1989). It is May–August in most of its range but February–April in Panama. The tiger heron nests solitarily in trees above the water, especially in mangroves (Rhizophora). Nests are small to large platforms made of sticks usually lined with leaves. They are placed on branches 4-15 m above the ground.


Courtship is little understood in this species, and the displays reported have little context to them (Dickey and van Rossem 1938 Sutton et al. 1950, Wetmore 1965). The primary display appears to be a version of the Stretch—a pair faced each other, necks and bodies crouched horizontally, feathers fluffed up; the birds raise their bills and neck vertically, depressing the neck and body feathers, and emitting two or three hoarse booms or roars. They may sway the neck at the vertical. This may be repeated, and one bird may move toward the other. Mutual Bittern posture has also been described.


Eggs are dull white with a green tinge, rarely flecked with brown or buff. The usually unspotted eggs are not typical of the tiger herons (Dawn 1964). Two measured 56.6 x 43.5 mm and 58.1 x 45.3 mm. Clutches are 1-3 eggs. There is no information on incubation, chick development or fledging and little is known about the nesting success of this species. Nestlings are at risk to hawk (Buteogallus) predation (Lewis and Timm 1991).


The bare throat of this species was recognized for years as being highly distinctive. It is now placed in the same genus as the other two South American tiger herons. The tiger herons are a distinctive lineage of the Ardeidae, adapted to a forest existence. The five species constitute a sister group to all the other herons and bitterns and to the Boat Billed Heron (Sheldon et al. 1995).

The Bare-throated Tiger-Heron occurs in coastal Mexico, Central America, and northern South America.


Breeding range: In Mexico, it occurs as far north as south Tamaulipas and south Sonora, along both coasts, across the Isthmus of Tehuantepec, in all of the Yucatan, coastal in Central America through Panama, including Coida Island and Perles Archipelago but of limited distribution on the Caribbean slope, into extreme north west Colombia from Gulf of Urabá to the lower Atrato River valley.

Sunday, 16 April 2017

28-3-2017 TARCOLES RIVER COSTA RICA - BARE THROATED TIGER HERON (Tigrisoma mexicanum)


The bare-throated tiger heron (Tigrisoma mexicanum) is a wading bird of the heron family, Ardeidae, found from Mexico to northwestern Colombia, with one recorded sighting from the United States in Hidalgo County, Texas. It is 80 cm (31 in) in length and weighs 1,200 g (42 oz).

This large species is found in more open habitats than other Tigrisoma herons, such as river and lake banks. It waits often motionless for suitable prey such as fish, frogs or crabs to come within reach of its long bill.


This is a solitary breeder, not normally found in heron colonies. The nest is a small flattish stick platform in a tree into which 2–3 green-tinged white eggs are laid.

The throat is bare and is greenish-yellow to orange in all plumages. The adult has black crown and light grey sides of the head, the sides of the neck and the upperparts otherwise blackish narrowly barred buff. The median stripe down the fore-neck is white-bordered with black; the remaining underparts are dull cinnamon brown. The juvenile is buff coarsely barred with black, more mottled and vermiculated on wings; the throat, median underparts, and belly are whitish.


The flight is heavy, and the call is a hoarse howk-howk-howk. Males also give a booming hrrrowwr! call, especially at sunset. During emission of the call, the beak opens wide and undulations can be seen along the course of the throat from mid-thorax caudally.


A large but short-legged primitive-looking heron of mangroves and freshwater wetlands in tropical lowlands. Usually found in wooded areas, but also in lagoons in open wetlands. It has a bare yellow throat in all plumages (not always visible) and greenish legs. The adult has grey cheeks, finely barred plumage and rusty brown thighs. The immature has very conspicuous blackish and bright brown barring (hence the name Tiger Heron).

The rufescent tiger heron is found in wetlands from Central America through much of South America. It generally occurs below 500 m (1,600 ft), though it has been recorded as high as 1,600 m (5,200 ft) in Colombia.