Seminar: 'Hunting without vision: tactile senses and foraging in kiwi and other probing' by Susan Cunningham

Susan Cunningham is a postdoctoral fellow at the Percy FitzPatrick Institute. She will present her PhD which is currently under examination at Massey Univ., New Zealand.

DATE: Tuesday, 8 June 2010
TIME: 13h00
VENUE: Niven Library, Zoology Building, UCT

Abstract: The majority of birds rely heavily on visual information, both for foraging and in other aspects of their lives. Probing birds, however, target prey which are generally hidden from view. They must therefore rely on senses other than vision when foraging. Some probing birds are able to detect vibration and pressure cues from prey hidden within granular or aquatic substrates, using a sensory system known as ‘remote touch.’ This sense, alien to humans, is mediated by a tactile bill-tip organ, first described from the shorebird family Scolopacidae. During my research, I showed that the Scolopacid-type bill tip organ is also present in kiwi (Apterygidae), ibises (Threskiornithidae), and possibly some rail species (Rallidae). I used a combination of 3D microCT scanning and traditional anatomy and histology to compare bill-tip structure between these families. I also conducted foraging experiments with kiwi and ibises in captivity to confirm that their bill-tip organs were functional for remote touch. The Scolopacidae, Apterygidae, Threskiornithidae and Rallidae are not closely related; suggesting that convergent evolution of remote touch is favoured by a probe-foraging lifestyle. Wild kiwi are incredibly cryptic due to their nocturnal habits and forested habitat. Previous studies of these birds have therefore relied exclusively on sign, radio telemetry & mark-recapture data. I used direct focal observations of wild kiwi (obtained with infrared cameras) to document their behaviour patterns for the first time, and to make inferences about their sensory world.