SPECIES

Principe Scops-Owl Otus bikegila Scientific name definitions

Bárbara Freitas and Martim Melo
Version: 1.0 — Published October 24, 2023

Identification

Field Identification

Principe Scops-Owl is a small scops-owl (Otus) with a rounded and packed appearance as it rarely raises the ear-tufts in the wild. The only occasions of raised ear-tufts were documented when a bird was flushed accidentally during daytime and when birds are handled by researchers. On these occasions, the overall appearance changes dramatically, both in shape and in color – with the eyebrow feathers (internal side of the facial disk) revealing their white underside to create two striking white bands. Two color morphs, not related to sex, occur: a deep rufous morph and a morph with gray face and underparts and a rufous back. The female is slightly larger than the male, something only noticeable if individuals of both sexes are observed close together.

As with most species of scops-owls in the genus Otus, a unique and clearly distinctive main call constitutes the unambiguous diagnostic trait for the species. It consists in a short, undulated tweeu note repeated at a fast rate of ca. 1 note/second (see Vocalizations), recalling the calls of the distantly related Sokoke Scops-Owl (Otus ireneae) or the Red-chested Owlet (Glaucidium tephronotum).

Similar Species Summary

No other owl species occurs on Principe Island, thus there should be few identification challenges.

Similar Species

Morphological differences from other scops-owls, although present (1), do not stand out to the human-eye, as plumage evolution in the group is driven by the shared pressure to remain cryptic during daytime, leading to the convergent evolution of similar camouflaged patterns across species (15, 16). In overall appearance, Principe Scops-Owl most closely resembles Sao Tome Scops-Owl (Otus hartlaubi), but with smaller and finer black spots.

Recommended Citation

Freitas, B. and M. Melo (2023). Principe Scops-Owl (Otus bikegila), version 1.0. In Birds of the World (N. D. Sly, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.prisco1.01