Sri Lanka Grey Hornbill Ocyceros gingalensis


Justification of Red List Category
Although this species may have a restricted range, it is not believed to 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). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to 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.

Population justification
The global population size has not been quantified, but the species is reported to be locally common (del Hoyo et al. 2001). Surveys were carried out in one district in Sri Lanka in 2014 and 2015 (Wickramasinghe et al. 2018), which showed higher presence and distribution within non-forested habitats such as gardens and remnant forest patches. However population or density estimates are not available.

Trend justification
The population is suspected to be stable in the absence of evidence for any declines or substantial threats.

Distribution and population

The species is endemic to Sri Lanka. It is estimated that only 2,492 km2 of its habitat is optimal (Poonswad et al., 2013).


Besides lowland moist dense forests, they also occur in cultivated and hilly areas. Tree species used mostly for nesting were Manilkara hexandra (50%) and Azadirachta indica (30%) in Anuradhapura (Wickramasinghe et al. 2018). Nest trees were recorded in and around Protected Areas, home gardens and remnant forest patches (Wickramasinghe et al. 2018). 
The nesting season for the species is from March to June. The average length of each nesting cycle is 104±6 days. The female emerges from the nest after 76±5 days (Wijerathne and Wickramasinghe 2018). 1-3 eggs are laid by the female, which typically undergoes a full moult of flight feathers before being incarcerated (Poonswad et al. 2013). A study by Wijerthne and Wickramasinghe (2018) found that in the early part of the day, 83% of food delivered to the female comprised of figs, where as deliveries later in the day was 69% animal matter.


Text account compilers
Datta, A., Clark, J., Patil, I.

Butchart, S., Datta, A., Ekstrom, J. & Patil, I.

Recommended citation
BirdLife International (2022) Species factsheet: Ocyceros gingalensis. Downloaded from on 17/08/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from on 17/08/2022.