[order] CICONIIFORMES | [family] Ardeidae | [latin] Butorides striata | [authority] Linnaeus, 1758 | [UK] Striated Heron | [FR] Bouvreuil orange | [DE] Mangrovereiher | [ES] Garcita Azulada | [NL] Mangrovereiger
Subspecies
Monotypic species
Genus
Butorides is a genus of small herons. It contains three similar species, the Green Heron or Green-backed Heron, Butorides virescens, the Dwarf Bittern (Butorides sturmii), and the Striated Heron, Butorides striatus. A fossil species, Butorides validipes, is known from the Early Pleistocene of Florida. Adults of both extant species are about 44 cm long, and have a blue-black back and wings, a black cap and short yellow legs. Juveniles are browner above and streaked below, and have greenish-yellow legs. The species have different underpart colours, chestnut with a white line down the front in Green Heron, and white or grey in Striated. Both breed in small wetlands on a platform of sticks often in shrubs or trees, sometimes on the ground. Butorides herons stand still at the water’s edge and wait to ambush prey. They mainly eat small fish, frogs and aquatic insects. They sometimes drop food on the water’s surface to attract fish.
Physical charateristics
The Striated Heron is a small-sized heron. Its plumage can be very varied according to the geographical range. Most of the races are different first by head and neck colour, and by the size.
The striated Heron is greenish grey, neck is short, and crown is very dark green with a long crest of the same colour, almost black. Rear neck and sides are chestnut brown. Upperparts are dark green. Underparts are pale grey, throat and chest are white.
Bill is long and powerful, with black upper mandible, and yellow lower mandible. Legs and feet are pale yellow to orange. Face is greenish.
Adults and young have a partial web between central and external toe, allowing them to swim.
Juvenile is brownish, with well striated neck, and with whitish and buffy spots on upper wings. Throat, neck and chest are streaked with brown. Legs are green.
The striated Heron is greenish grey, neck is short, and crown is very dark green with a long crest of the same colour, almost black. Rear neck and sides are chestnut brown. Upperparts are dark green. Underparts are pale grey, throat and chest are white.
Bill is long and powerful, with black upper mandible, and yellow lower mandible. Legs and feet are pale yellow to orange. Face is greenish.
Adults and young have a partial web between central and external toe, allowing them to swim.
Juvenile is brownish, with well striated neck, and with whitish and buffy spots on upper wings. Throat, neck and chest are streaked with brown. Legs are green.
Listen to the sound of Striated Heron
[audio:http://www.planetofbirds.com/MASTER/CICONIIFORMES/Ardeidae/sounds/Striated Heron.mp3]
Copyright remark: Most sounds derived from xeno-canto
| wingspan min.: | 62 | cm | wingspan max.: | 68 | cm |
| size min.: | 40 | cm | size max.: | 45 | cm |
| incubation min.: | 21 | days | incubation max.: | 25 | days |
| fledging min.: | 34 | days | fledging max.: | 25 | days |
| broods: | 1 | eggs min.: | 3 | ||
| eggs max.: | 6 |
Range
South America, Eurasia, Africa, Australasia : widespread
Habitat
Striated Heron lives close to fresh and salt waters, in mangroves, in dense vegetation areas, along streams, lakes, rivers, ponds, in estuaries, and in open areas such as mudflats, tidal areas or coral reefs.
Reproduction
The nest is well hidden between the branches of bushes or trees, at about 2 to 10 meters above ground or water. It is made with a few twigs, in a loose manner, and after laying, the eggs can be seen from below. Nest is 30 cm wide and 5 cm deep. Female lays 2 to 5 pale greenish blue eggs. Incubation lasts 20 to 25 days, shared by both parents, also both adults raise the young. The young are fed by both parents at the nest by regurgitation. Young remain at nest until they fledge, at about 4 weeks of age.
If the family is disturbed or threatened, the young may leave the nest and perch in branches, in order to confuse a predator.
If the family is disturbed or threatened, the young may leave the nest and perch in branches, in order to confuse a predator.
Feeding habits
Striated Heron feeds on fish and amphibians, insects, spiders, crabs, shrimps and other shellfish, reptiles, sometimes even mice and other small mammals.
Video Striated Heron
httpv://www.youtube.com/watch?v=Shicru8t-SQ
copyright: P. de Groot Boersma
Conservation
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Striated Heron is generally resident in its range. It usually fishes at dusk and during the night, but also sometimes during the day foraging into the marsh dense vegetation. But it sometimes fishes during the day, in urban areas, where we can see it walking slowly on the shore of a pond, or perched on a pier or a boat. We often meet it in a compact position, in egg-shaped posture, perched on a branch above water, looking intentionally elsewhere.
Its plumage is a very good camouflage. It usually hunts under cover, rarely in open area, waiting from a elevated position to strike quickly, it also may jump, dive or swim after its prey. Or it stirs up and scrapes the water surface to attract prey by movement. But the most stunning fact is that it knows how to attract them. It captures an insect and drops it to the surface, which of course, attracts fish or other preys. It also catches flying insects.
Striated Heron is generally resident in its range. It usually fishes at dusk and during the night, but also sometimes during the day foraging into the marsh dense vegetation. But it sometimes fishes during the day, in urban areas, where we can see it walking slowly on the shore of a pond, or perched on a pier or a boat. We often meet it in a compact position, in egg-shaped posture, perched on a branch above water, looking intentionally elsewhere.
Its plumage is a very good camouflage. It usually hunts under cover, rarely in open area, waiting from a elevated position to strike quickly, it also may jump, dive or swim after its prey. Or it stirs up and scrapes the water surface to attract prey by movement. But the most stunning fact is that it knows how to attract them. It captures an insect and drops it to the surface, which of course, attracts fish or other preys. It also catches flying insects.
Migration
Majority of races sedentary, most northerly races migratory. Race virescens passes through USA mostly in September-October, wintering from Florida, Southern Texas and Mexico to West Indies and Northern South America, from Ecuador to Surinam, moves by day or night. Both sexes return to breeding zones at same time, in March-April. General tendency towards post-breeding dispersal, sometimes leading to irruptions. Also recorded as vagrant, race virescens crossing Atlantic or far into Pacific.
Distribution map
Literature
Title The Relation of Hunting Site Changes to Hunting Success in Green Herons and Green Kingfishers
Author(s): Burr J. Betts Donna L. Betts
Abstract: Considerable information is available on the feedi..[more]..
Source: Condor: Vol. 79, No. 2