Assiolo di Giava

Tassonomia

Javan scops owl is possibly closest to the O. brookii. Sometimes treated as a subspecies of O. brookii or O. spilocephalus, it is currently defined as a separate species because of differences in morphology and vocal habit.

Nome scientifico

Otus angelinae

Autorità

(Finsch, 1912)

Ordine

Strigiformi

Famiglia

Strigidae

Genere

Otus

Areale e habitat

These birds are endemic to West Java's highland forest. Their traces were discovered in the mountains of Mount Salak, Mount Pangrango, Mount Gede, and Mount Tangkuban Perahu; their appearances were also historically reported in the Papandayan and Ciremay areas.<p>The Javan scops owl prefers montane forest with a well-developed understory at elevations ranging from 1500 to 2000m. Their documented living elevation ranges from 900 to 2500 metres. They prefer to dwell in the lower and middle canopy layers with a broader variety of tree species.

Migrazione

Resident species

Comportamento

Insects like beetles, grasshoppers, crickets and mantis comprise the main portion of their diet. There have been reports of tiny lizards and snakes being consumed occasionally.<p>Javan scops owl can deliver beetles (Coleoptera), mantids (Mantodea), stick insect (Phasmatodea), grasshoppers (Tettigoniidae, Orthoptera), and crickets (Gryllidae, Orthoptera) to feed the fledged offspring. In terms of foraging, they use their keen vision and acute hearing to track down their prey and snare it from the trunk, foliage, or the ground.<p>While most scops owls usually make themselves known by their persistent vocalizations, the Javan scops owl is relatively quiet. The bird's alarm calls are repeated explosive "poo-poo" with a 0.5-second delay and a pitch decrease between the two notes. This call will be repeated multiple times and often has a trembling quality. The contact call of these birds is a hissing "tch-tschschsch". The male bird can also produce a lower and soft comfort call like "wook-wook."<p>Three family units with two newly fledged young were reported in previous literature, one in early February and the other two in early July. Based on these observations, laying is predicted to occur in the second weeks of December and May, respectively, and the clutch size is most likely two eggs.

Conservazione

The Javan scops owl is listed as vulnerable on the IUCN Red List. Its activity range is limited to the forests of Java and Bali. While it is considered rare by most authors, it is somewhat more common in the montane forest above 1,400m on Mount Salak. Its secretive behaviour and silent habits make the estimation of the bird population very difficult. This species' worldwide population is estimated to be between 1500 and 1700 individuals, with a declining tendency owing to forest fragmentation.<p>The population has been documented in two protected areas: Mount Halimun Salak National Park and Mount Gede Pangrango National Park. These protected areas encompass around 500 km2 (190 sq mi) of woodland with elevations up to 3,000 m (9,800 ft). There are also nature reserves on Mount Tangkuban Prahu and Ijen, where previous Javan scops owl's records exist. Proposed future conservation actions on this species include conducting extensive nocturnal research (including mist-netting) on Java's highlands to determine the exact range and population status of O. angelinae, as well as the creation of more protected montane area.

Tendenza della popolazione

declining