DO TENGMALMS OWLS SEE VOLE SCENT MARKS VISIBLE IN ULTRAVIOLET-LIGHT

Scent markings (urine and faeces) of small mammals are visible in ultr aviolet (UV) light. Diurnal kestrels, Falco tinnunculus, use them as a cue to find areas of food abundance. We studied whether vole-eating, nocturnal Tengmalm's owls, Aegolius funereus, can see vole scent marks using W-vision. In a laboratory experiment, 14 young (less than 6 mon ths old) and 14 adult (more than 6 months old) owls were individually given a choice between four adjacent arenas: (1) an arena with vole ur ine and faeces in UV light; (2) an arena with vole urine and faeces in visible light; (3) a clean arena in UV light; and (4) a clean arena i n visible light. Owls did not prefer any of the four arenas. Our resul ts suggest that Tengmalm's owls probably do not use UV light as a cue to detect vole scent marks. (C) 1997 The Association for the Study of Animal Behaviour.