Visual abilities in two raptors with different ecology
(2016) In Journal of Experimental Biology 219(17). p.2639-2649- Abstract
Differences in visual capabilities are known to reflect differences in foraging behaviour even among closely related species. Among birds, the foraging of diurnal raptors is assumed to be guided mainly by vision but their foraging tactics include both scavenging upon immobile prey and the aerial pursuit of highly mobile prey. We studied how visual capabilities differ between two diurnal raptor species of similar size: Harris's hawks, Parabuteo unicinctus, which take mobile prey, and black kites, Milvus migrans, which are primarily carrion eaters. We measured visual acuity, foveal characteristics and visual fields in both species. Visual acuity was determined using a behavioural training technique; foveal characteristics were determined... (More)
Differences in visual capabilities are known to reflect differences in foraging behaviour even among closely related species. Among birds, the foraging of diurnal raptors is assumed to be guided mainly by vision but their foraging tactics include both scavenging upon immobile prey and the aerial pursuit of highly mobile prey. We studied how visual capabilities differ between two diurnal raptor species of similar size: Harris's hawks, Parabuteo unicinctus, which take mobile prey, and black kites, Milvus migrans, which are primarily carrion eaters. We measured visual acuity, foveal characteristics and visual fields in both species. Visual acuity was determined using a behavioural training technique; foveal characteristics were determined using ultra-high resolution spectraldomain optical coherence tomography (OCT); and visual field parameters were determined using an ophthalmoscopic reflex technique. We found that these two raptors differ in their visual capacities. Harris's hawks have a visual acuity slightly higher than that of black kites. Among the five Harris's hawks tested, individuals with higher estimated visual acuity made more horizontal head movements before making a decision. This may reflect an increase in the use of monocular vision. Harris's hawks have two foveas (one central and one temporal), while black kites have only one central fovea and a temporal area. Black kites have a wider visual field than Harris's hawks. This may facilitate the detection of conspecifics when they are scavenging. These differences in the visual capabilities of these two raptors may reflect differences in the perceptual demands of their foraging behaviours.
(Less)
- author
- Potier, Simon ; Bonadonna, Francesco ; Kelber, Almut LU ; Martin, Graham R. ; Isard, Pierre François ; Dulaurent, Thomas and Duriez, Olivier
- organization
- publishing date
- 2016-09-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Black kite, Fovea, Harris's hawk, Raptor vision, Visual acuity, Visual field
- in
- Journal of Experimental Biology
- volume
- 219
- issue
- 17
- pages
- 11 pages
- publisher
- The Company of Biologists Ltd
- external identifiers
-
- pmid:27317812
- wos:000384249800014
- scopus:84988646786
- ISSN
- 0022-0949
- DOI
- 10.1242/jeb.142083
- language
- English
- LU publication?
- yes
- id
- 730fa44f-c228-4283-a601-198974524cd2
- date added to LUP
- 2016-12-13 12:02:10
- date last changed
- 2024-01-04 18:48:58
@article{730fa44f-c228-4283-a601-198974524cd2,
abstract = {{<p>Differences in visual capabilities are known to reflect differences in foraging behaviour even among closely related species. Among birds, the foraging of diurnal raptors is assumed to be guided mainly by vision but their foraging tactics include both scavenging upon immobile prey and the aerial pursuit of highly mobile prey. We studied how visual capabilities differ between two diurnal raptor species of similar size: Harris's hawks, Parabuteo unicinctus, which take mobile prey, and black kites, Milvus migrans, which are primarily carrion eaters. We measured visual acuity, foveal characteristics and visual fields in both species. Visual acuity was determined using a behavioural training technique; foveal characteristics were determined using ultra-high resolution spectraldomain optical coherence tomography (OCT); and visual field parameters were determined using an ophthalmoscopic reflex technique. We found that these two raptors differ in their visual capacities. Harris's hawks have a visual acuity slightly higher than that of black kites. Among the five Harris's hawks tested, individuals with higher estimated visual acuity made more horizontal head movements before making a decision. This may reflect an increase in the use of monocular vision. Harris's hawks have two foveas (one central and one temporal), while black kites have only one central fovea and a temporal area. Black kites have a wider visual field than Harris's hawks. This may facilitate the detection of conspecifics when they are scavenging. These differences in the visual capabilities of these two raptors may reflect differences in the perceptual demands of their foraging behaviours.</p>}},
author = {{Potier, Simon and Bonadonna, Francesco and Kelber, Almut and Martin, Graham R. and Isard, Pierre François and Dulaurent, Thomas and Duriez, Olivier}},
issn = {{0022-0949}},
keywords = {{Black kite; Fovea; Harris's hawk; Raptor vision; Visual acuity; Visual field}},
language = {{eng}},
month = {{09}},
number = {{17}},
pages = {{2639--2649}},
publisher = {{The Company of Biologists Ltd}},
series = {{Journal of Experimental Biology}},
title = {{Visual abilities in two raptors with different ecology}},
url = {{http://dx.doi.org/10.1242/jeb.142083}},
doi = {{10.1242/jeb.142083}},
volume = {{219}},
year = {{2016}},
}