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Issue: Vol. 5752 No. 3: 28 Jan. 2026
Type: Article
Published: 2026-01-28
DOI: 10.11646/zootaxa.5752.3.5
Page range: 399-416
Abstract views: 46
PDF downloaded: 2

Morphological assessment of the Common Barn Owl Tyto alba (Strigiformes: Tytonidae) supports three species

55732 Ninepipe Rd; Charlo; MT 59824; USA
Global Owl Project; Buckeystown; MD; USA
Centro de Investigaciones en Ecología y Zonas Áridas Sabana Larga; Santa Ana de Coro; Estado Falcón; Venezuela
Centro de Investigaciones en Ecología y Zonas Áridas Sabana Larga; Santa Ana de Coro; Estado Falcón; Venezuela
Instituto de Salud Agricola Integral; Calabozo estado Guárico; Venezuela
Universidade Estadual de Maringá; Maringá; Paraná; Brazil
Department of Biology; Walla Walla University; Walla Walla; WA; USA
Global Owl Project; Alexandria; VA; USA
Aves Taxonomy Conservation Morphometrics

Abstract

Barn owls (Tytonidae: Tyto) have long been considered a single species, despite their worldwide distribution and despite being highly geographically variable in morphology. Multiple genomic studies have now demonstrated that the Common Barn Owl Tyto alba sensu lato complex has at least three deeply genetically diverged evolutionary units: Tyto alba sensu stricto, occurring from southern Scandinavia to South Africa; Tyto furcata, of southern Canada to Patagonia; and Tyto javanica, of the Himalayan plateau to Tasmania and the tropical Pacific. Their extensive geographic variation, however, greatly complicates delineation of their taxonomy. With the aim of shedding further light on barn owl taxonomy, we conducted a comprehensive morphological analysis of the three major Tyto alba s.l. clades, measuring up to 21 different morphometrics on 192 live and 1271 museum barn owl specimens. Our results clearly demonstrated mensural differences between the three evolutionary species units of barn owls, primarily in that the several subspecies of Tyto furcata as a clade are, sex-for-sex, considerably larger than the other two clades, especially in wing length. Despite Tyto javanica being sister to the other two clades and being somewhat intermediate in size, its several subspecies are more similar in overall size to subspecies of Tyto alba s.s. (the smallest-bodied clade) than either is to Tyto furcata. Our research supports and supplements the genetic and vocal evidence that recently led to the now widely adopted subdivision of the Barn Owl Tyto alba s.l. into three separate species.

 

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How to Cite

Daugherty, R.L., Iii, A.J.B., Salas, V.G., Contreras, F.J., Chávez, R., Mendes, G.C., Nestler, J.R. & Johnson, D.H. (2026) Morphological assessment of the Common Barn Owl Tyto alba (Strigiformes: Tytonidae) supports three species. Zootaxa, 5752 (3), 399–416. https://doi.org/10.11646/zootaxa.5752.3.5