Ardea
Official journal of the Netherlands Ornithologists' Union

login


[close window] [previous abstract] [next abstract]

Hardy A.R., Hirons G.J.M., Stanley P.I. & Huson L.W. (1981) Sexual dimorphism in size of Tawny Owls (Strix aluco): a method for sexing in field studies. ARDEA 69 (2): 181-184
A practical method is presented to externally distinguish between male and female Tawny Owls which have an identical range of plumage variation. From the wing lengths and body weights of 142 dead Tawny Owls, collected mainly as road casualties throughout England and Wales and sexed by dissection, a linear discriminant function was calculated. This correctly classified 89% of the sample and when compared with measurements Of 42 live Tawny Owls of known sex, correctly classified 95%. Strong sexual dimorphism is exhibited with the female on average 4.3% longer in the wing and 26.2% heavier than the male.


[close window] [previous abstract] [next abstract]