Justification of Red List category
Given the continuing habitat destruction and degradation taking place in its range, the apparently small population of this elusive owl is likely to be declining and fragmented. As a result, it qualifies as Vulnerable.
The population is estimated to number 2,500-9,999 mature individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size; its description as being uncommon or rare, and the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied. This estimate is equivalent to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.
Forest loss below 1,000 m on the Minahas peninsula has been near total and continues in other parts of the species's range. As a result it is suspected to be declining at a moderate rate.
Tyto inexspectata is endemic to Sulawesi, Indonesia, where it is known from 11 specimens collected on the Minahasa peninsula and north-central regions of the island, and a few subsequent records (BirdLife International 2001). A number of recent records have come from Tangkoko National Park (F. Verbelen in litt. 2012). It appears to be sparsely distributed, and has been described as very uncommon or rare. However, it is shy, easily overlooked, and consequently almost certainly more abundant than records suggest. Numbers are likely to have declined steadily in line with on-going habitat loss.
It inhabits primary and lightly disturbed rainforest, rich with lianas, ferns, palms and epiphytic plants, and also, at least occasionally, disturbed riverine forest and forest edge, from 100 m to 1,600 m. It is presumably sedentary.
The loss, degradation and fragmentation of forests pose the major threat to the species. It has doubtless contracted in range in the lowlands of Sulawesi, particularly on the Minahasa peninsula, as a result of land clearance for transmigration settlements, agricultural and infrastructural development and large-scale logging. Destruction of lowland forest on the Minahasa peninsula is described as almost complete, and most primary forest below 1,000 m has been reduced to remnant patches, supplanted by secondary, disturbed and commercially utilised forest. Recent records of the species from higher altitudes provide some hope that healthy populations survive in more secure montane forests. In Indonesia, new regional autonomy laws were passed in 1999 (and enacted in early 2000); these empower regional governments to determine the licensing of forest concessions and exploitation of natural resources. Unfortunately there has been a significant increase in the amount of logging taking place in protected areas since decentralisation, especially in Sulawesi.
Conservation Actions Underway
CITES Appendix II. It is known to occur in two protected areas, Bogani Nani Wartabone and Lore Lindu National Parks, which have been described as two of the largest, biologically most important and best administered parks in Wallacea. In addition, 21 protected areas, with a total area of c.9,000 km2, have been proposed and/or established within the known range of the species.
30 cm. Medium-small, forest-dwelling owl. Light rusty facial disk. Rusty upperparts speckled black, rusty-cream underparts spotted black, wings barred black and rufous. Finely barred tail. Nuchal area and bend of wing darker than rest of plumage. Black iris. Similar spp. Sulawesi Owl T. rosenbergi is much larger, with dusky facial disc and upperparts finely spotted white. There are two morphs of this species, of which the darker is most difficult to differentiate from T. rosenbergi. Voice Single nasal, hoarse, hissing shriek lasting about 1.8 seconds and delivered infrequently every 5-7 minutes (Mauro and Drijvers 2000).
Text account compilers
Benstead, P., Bird, J., Taylor, J., Tobias, J., Allinson, T
Bishop, K., Verbelen, F.
BirdLife International (2023) Species factsheet: Tyto inexspectata. Downloaded from http://datazone.birdlife.org/species/factsheet/minahasa-masked-owl-tyto-inexspectata on 09/12/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 09/12/2023.