Mindoro Owl
| Mindoro Owl | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||
|
||||||||||
| Scientific name | ||||||||||
| Ninox mindorensis | ||||||||||
| Ogilvie-Grant , 1896 |
The Mindoro Owl ( Ninox mindorensis ) belongs to the genus of the bush owls . It is only native to Mindoro , a western island of the Philippines .
description
Dimensions
The Mindoro Owl is a small owl about 20 cm tall. The length of the wing from the bow (elbow joint) to the tip of the longest hand wing is 159 to 176 mm in the male, 154 to 171 mm in the female, the tail is 74 to 92 mm long. Two males have so far been weighed with 108 and 118 g, two females with 100 and 105 g.
Appearance
The face fletching is reddish brown. The stripe above the eyes between the base of the beak and the yellow eyes is whitish, but forms only a weak contrast to the surrounding color. The bill and nasal wax skin are bluish gray. The Mindoro Owl does not have feather ears .
The head and neck are matt reddish brown with dense, fine dark ocher colored horizontal stripes. The mantle feathers are warm brown with weakly recognizable, dense darker stripes. The shoulder feathers are provided with inconspicuous whitish points at the tip, the feather covers are warm brown with pale ocher-colored points. The relatively long flight feathers are brown with paler ribbons. The tail feathers are also warm brown and have narrow, ocher-colored horizontal stripes.
The throat is whitish with some dark spots and stripes in the upper neck region. Breast and belly are orange to reddish brown with dense, dark brown horizontal stripes, the color becomes lighter to ocher gray downwards. The proximal two-thirds of the legs are partly orange to ocher-colored, the distal third is bare and yellowish-gray like the bristle toes. The claws are dark horn colored.
There are still no records of the appearance of the young birds.
Distinguishing features
The congeneric chocolate owl ( Ninox randi ) also occurs on Mindoro . However, it is much larger than the Mindoro Owl, and along the belly there are strong chestnut brown and bright white colored feathers in clear contrast to each other. They have a white spot between their eyes.
The Philippine owl ( Ninox philippensis ) is slightly smaller than the Mindoro owl at 15 to 18 cm. The chest and abdomen are paler in color with unformed, broad brownish longitudinal stripes. The vocalizations also differ significantly from one another. The Philippine owl has not yet been observed on Mindoro, so it is not possible to confuse the two species in nature.
voice
The male emits a series of high-pitched growling whistles. Individually they start with a high, snickering whistle and end in a screeching scream that can be compared to the "scream" of the barn owl ( Tyto alba ). They are repeated in an interval of one to two seconds: cheehrr cheehrr cheehrr ... , sometimes also cheehrr-ke cheehrr-ke ...
Distribution and habitat
The Mindoro Owl is endemic as a resident bird on the Philippine island of Mindoro. There it occurs from the flatlands to altitudes of 1,250 m above sea level in wooded areas.
behavior
The nocturnal Mindoro Owl can be observed at dusk. It breeds in knotholes, but details of the breeding behavior are not yet known.
nutrition
The main source of food for the Mindoro owl are mainly insects and small vertebrates.
Endangerment and species protection
The Mindoro Owl is classified as endangered by the International Union for Conservation of Nature (IUCN) and BirdLife International , as it is increasingly being pushed back by humans in its habitat. Appendix II of the Washington Convention on the Protection of Species applies to this species .
The populations continue to decline due to ongoing deforestation, mining and agricultural development. The number of individuals is roughly estimated at 2,500 to 10,000. The largest populations are found in the larger remaining lowland forests near the penal colony at Sablayan and in Mounts Iglit-Baco National Park and Naujan Lake National Park , but even these sanctuaries are not safe from habitat destruction by humans.
Further surveys to determine the population size and studies of the fundamental natural history of the Mindoro owl and its habitat connection are just as important as educational campaigns that focus on the importance of native species in order to be able to contribute to better protection of critical habitats.
Taxonomy
For the first time, Ogilvie-Grant described a specimen from the lowlands of Mindoro in his work On the Birds of the Philippine Islands , which appeared in several parts in the Ibis from 1894 to 1897 . Up until 2012, Ninox mindorensis , N. philippensis , N. reyi , N. spilocephala and N. spilonotus were considered con-specifically . After further investigations, Pamela C. Rasmussen and her team were able to classify them as separate species based on different vocalizations, plumage drawings and morphometry . The Mindoro Owl is monotypical , which means that to this day no subspecies have been distinguished.
literature
- Mindoro Boobook (Ninox mindorensis) . In: Josep del Hoyo Calduch et al. (Ed.): Handbook of the Birds of the World Alive . Lynx, Barcelona 2018.
- Claus König , F. Weick : Owls of the world . 2nd Edition. Helm, London 2008, ISBN 978-0-7136-6548-2 , pp. 184-197, 448-473 .
- William R. Ogilvie-Grant : On the Birds of the Philippine Islands. Part VII. The Highlands of Mindoro . In: Ibis . ser. 7, vol. 2, no. 8 . Oxford October 1896, p. 457-477 .
Individual evidence
- ↑ a b c d e f g h Pamela C. Rasmussen et al .: Vocal divergence and new species in the Philippine Hawk Owl Ninox philippensis complex . In: Forktail . Vol. 28, Newbury 2012, p. 1-20 .
- ↑ a b Thomas Brooks et al .: Siburan - key area for birds on Mindoro . In: Oriental Bird Club. Bulletin . tape 21 . Sandy July 1995, p. 28-33 .