Publication Type: | Journal Article |
Year of Publication: | 1984 |
Authors: | Simmons, R |
Journal: | Ostrich |
Volume: | 55 |
Issue: | 3 |
Date Published: | 1984 |
ISBN Number: | 0030-6525 |
Keywords: | Accipiter, Accipiter nisus, Accipiter rufiventris, Accipitridae, Struthio, Struthio camelus, Struthionidae |
Abstract: | Summary Simmons, Robert. 1984. Pre-independence behaviour, morphometrics and trapping of Redbreasted Sparrowhawks. Ostrich 55:158-162. During an intensive study of breeding Redbreasted Sparrowhawks Accipiter rufiventris, I developed a new technique of catching flying young by exploiting their innate curiosity about moving objects. Pine cones modified to resemble partially plucked birds were thrown past a perched sparrowhawk which dived at the cone and ?kneaded? it on the ground. While still grounded, fledglings were covered with a raptor mist net, and later weighed and measured. Birds were caught up to the time the last one became independent (76 days). Both fledglings could dive competently at cones soon after they could fly and by day 55 they were taking prey transfers on the wing. Independence was reached when both birds became food-stressed (57th and 76th days). Since the second fledgling had achieved 99% feather growth at independence, I suggest that the adults may assess their young's flight skills to determine when prey provisioning can cease.Summary Simmons, Robert. 1984. Pre-independence behaviour, morphometrics and trapping of Redbreasted Sparrowhawks. Ostrich 55:158-162. During an intensive study of breeding Redbreasted Sparrowhawks Accipiter rufiventris, I developed a new technique of catching flying young by exploiting their innate curiosity about moving objects. Pine cones modified to resemble partially plucked birds were thrown past a perched sparrowhawk which dived at the cone and ?kneaded? it on the ground. While still grounded, fledglings were covered with a raptor mist net, and later weighed and measured. Birds were caught up to the time the last one became independent (76 days). Both fledglings could dive competently at cones soon after they could fly and by day 55 they were taking prey transfers on the wing. Independence was reached when both birds became food-stressed (57th and 76th days). Since the second fledgling had achieved 99% feather growth at independence, I suggest that the adults may assess their young's flight skills to determine when prey provisioning can cease. |
URL: | http://www.tandfonline.com/doi/abs/10.1080/00306525.1984.9633625 |
Short Title: | Ostrich |
Taxonomic name: