Sound-Source Localization by the Red Fox

Searching for the Audience of the Weeping Lizard's Distress Call

“…). Foxes are attracted to distress calls (Morse & Balser ; Hödl & Gollmann ), and the red fox optimally locates sound sources at frequencies between 0.9 and 14 kHz (Isley & Gysel ), which includes frequencies emitted by the weeping lizard (Labra et al. ).…”

A behavioral audiogram of the red fox (Vulpes vulpes)

“…Within birds, species of the Phasianidae family constitute the main proportion (Lever, 1959;Goszczy nski, 1974;Hewson and Kolb, 1975;Dell'Arte et al, 2007). Red foxes have been shown to be most accurate in the localization of sounds between 3 and 4 kHz and this has been proposed to help finding common pheasant-chicks (Phasianus colchicus) by their flock call which is pitched around 4 kHz (Heinz and Gysel, 1970;Isley and Gysel, 1975). This frequency region of best localization exactly coincides with the best absolute hearing sensitivity of the red fox.…”

“…Rustling noise is broadband but contains most energy in bands at 8e10 kHz and their first harmonics (Konishi, 1973;Marimuthu and Neuweiler, 1987;Payne, 1971). Even though the ability of the red fox to localize pure tones is lowest at these frequencies, they can still provide reliable spatial information, probably enough to allow for increased hunting success at shorter distance (Isley and Gysel, 1975). In contrast to rustling sounds (crunching grass), the vocalizations of voles and mice are mainly ultrasonic between 50 and 70 kHz (Sewell, 1968).…”

“…This is indicated by the stereotypic approach behavior before a mousing jump during which the fox cocks its ears and carefully positions and repositions the head to facilitate sound localization ( Cervený et al, 2011). The sound localization ability of red foxes is highly accurate (resolution down to approximately 4 ) and frequency dependent (Isley and Gysel, 1975;€ Osterholm, 1964). Isley and Gysel (1975) concluded that the latter results from a switch between reliance on phase differences at low frequencies and intensity differences at high frequencies.…”

“…The sound localization ability of red foxes is highly accurate (resolution down to approximately 4 ) and frequency dependent (Isley and Gysel, 1975;€ Osterholm, 1964). Isley and Gysel (1975) concluded that the latter results from a switch between reliance on phase differences at low frequencies and intensity differences at high frequencies. On the other hand the authors acknowledged that, since no audiogram was available to them, the observed differences in the localization of pure tones of different frequencies could simply be a consequence of the auditory sensitivity.…”