Data Zone
Justification of Red List category
This species is suspected to have a small population, known only from four montane forest areas, that is suspected to be declining due to the ongoing clearance and degradation of its forest habitat. The paucity of records even from the well-surveyed parts of the range cause concern and the species is assessed as Near Threatened. Determining the population size is an urgent priority.
Population justification
The species is only known from 3-5 specimens and a handful of field records, most from Nyungwe where it is clearly very rare (F. Dowsett-Lemaire in litt. 2016). However, the specimens are from poorly studied sites that retain suitable habitat and are widely separated with large areas of apparently suitable habitat occurring in between. As a nocturnal species it may have been under-recorded by past ornithological surveys, and it may be fairly common in parts of Itombwe (T. Butynski in litt. 1999). Based on known records and the likely extent of suitable habitat within the inferred range, the population is provisionally suspected to number 2,500-9,999 mature individuals, which is consistent with recorded population density estimates for congeners or close relatives with a similar body size. This is equivalent to 3,750-14,999 individuals, rounded here to 3,500-15,000 individuals. The population may however be smaller, given the apparent very low densities in Nyungwe Forest in particular.
Trend justification
The population is suspected to be declining in line with the clearance and degradation of forest within the species's range. Tree cover loss within the range is currently estimated to be 10-16% across ten years (Global Forest Watch 2021, using Hansen et al. [2013] data and methods disclosed therein). This rate is expected to continue in the absence of action to mitigate current drivers of forest loss. This is considered to be a highly forest dependent species and therefore assuming that population declines are roughly equivalent to the rate of forest loss, the species may be declining at a rate of up to 20% over ten years.
This species is known from just five specimens, collected in the Itombwe Mountains (two specimens) and in forest west of Lake Edward (two at relatively low altitude [1,100 m] were originally identified as G. capense castaneum [Prigogine 1953] and may need re-examination [F. Dowsett-Lemaire in litt. 2000]), Democratic Republic of Congo (DRC), and one from Nyungwe Forest, Rwanda. There is a sight record from Kahuzi-Biéga National Park, west of Lake Kivu (DRC). It may be fairly common in parts of Itombwe (T. Butynski in litt. 1999) - as a nocturnal species, it may have been under-recorded by past ornithological surveys. The song of a barred owlet, assumed to be of this species, was heard in Nyungwe, Rwanda at the altitude of 2,500 m (Dowsett-Lemaire 1990) and there have been only two further undocumented records in 2015 and 2018 (eBird 2021); it is evidently very rare in Nyungwe (F. Dowsett-Lemaire in litt. 2016).
This species is found in very open montane and transitional forest, with many clearings and a dense understorey, and probably occurs up to 2,500 m at least (based on Glaucidium spp. heard calling at this altitude at Nyungwe, almost certainly G. albertinum [Dowsett-Lemaire 1990]). Its diet includes invertebrates, with a beetle and a grasshopper in the stomach of one bird (Holt et al. 2020). Its breeding ecology is unknown (Butynski et al. 1997).
Deforestation and forest degradation are the most likely threats throughout its range. Forest in the Itombwe Mountains and Kahuzi-Biéga National Park is under increasing pressure from pastoralists, farmers, pit-sawyers, miners and hunters (Hall et al. 1998, Omari et al. 1999). The human population in this volatile area is increasing rapidly and thousands of refugees from Burundi and Rwanda live in camps at the base of Itombwe's eastern escarpment and to the north (Hall et al. 1998, Omari et al. 1999). Clearance for agriculture, particularly along the southern and western edges of gallery montane forest, has increased dramatically in the past few years as maize crops have failed, causing famine (Butynski et al. 1997). Nyungwe Forest was initially reduced in size from 114,000 ha in 1958 to 97,100 ha in 1979, mainly at the expense of forest below 1,700 m (Fishpool & Evans 2001). Reports suggest that there was very little encroachment in the 1990s, due to the conflict-related emigration of local people (F. Dowsett-Lemaire in litt. 2000).
Conservation Actions Underway
CITES Appendix II. It occurs in Kahuzi-Biéga National Park and Nyungwe National Park. Itombwe Forest has been gazetted as a community reserve, although the boundaries still need to be defined (A. Plumptre in litt. 2007). Other parts of the Itombwe Mountains are not protected.
20 cm. Small, large-headed owl with no "ears". Rounded head heavily spotted with white. Mantle/back not barred. Barred breast. Spotted belly and flanks. Pale yellow eyes. Similar spp. African Barred Owlet G. capense is less intensely coloured, with barred head and mantle/back. Voice Not certainly described.
Text account compilers
Rotton, H.
Contributors
Butynski, T.M., Dowsett-Lemaire, F., Ekstrom, J., Evans, M., Khwaja, N., Plumptre, A., Shutes, S., Symes, A., Taylor, J. & Westrip, J.R.S.
Recommended citation
BirdLife International (2024) Species factsheet: Albertine Owlet Glaucidium albertinum. Downloaded from
https://datazone.birdlife.org/species/factsheet/albertine-owlet-glaucidium-albertinum on 26/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 26/11/2024.