Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

The identity, origin and impact of a 'new' buzzard species breeding in South Africa

South Africa is traditionally known to play host to two taxa of small Buteo, the endemic and uncommon Forest Buzzard B. trizonatus, and Steppe Buzzard B. b. vulpinus, an abundant Palearctic migrant. Since the late 1970s and early 1980s, a number of buzzards appearing unlike B. trizonatus have been f...

Full description

Saved in:
Bibliographic Details
Main Author: Gwynn, Lisle
Other Authors: Amar, Arjun
Format: Thesis
Language:English
Published: Percy FitzPatrick Institute of African Ornithology 2015
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613216688832512
access_status_str Open Access
author Gwynn, Lisle
author2 Amar, Arjun
author_browse Amar, Arjun
Gwynn, Lisle
author_facet Amar, Arjun
Gwynn, Lisle
author_sort Gwynn, Lisle
collection Thesis
description South Africa is traditionally known to play host to two taxa of small Buteo, the endemic and uncommon Forest Buzzard B. trizonatus, and Steppe Buzzard B. b. vulpinus, an abundant Palearctic migrant. Since the late 1970s and early 1980s, a number of buzzards appearing unlike B. trizonatus have been found breeding in the south-west Cape, particularly on the Cape Peninsula and in and around the Elgin Valley, ca.60km east of Cape Town. Some of these buzzards resemble B. b. vulpinus, whilst others appear atypical of both B. trizonatus and B. b. vulpinus. This study conducted genetic and morphological analyses on a number of buzzards sampled in the south-west Cape, and compared them with three candidate taxa considered most likely to, in full or in part, explain the identity of these ‘mystery’ buzzards. The candidate taxa were: Steppe Buzzard B. b. vulpinus, Ménétries’s Buzzard B. b. menetriesi and Forest Buzzard B. trizonatus. Morphology data and genetic samples were collected from 23 buzzards through capture with a Bal-Chatri trap, from chicks in nests, from captive birds brought to rehabilitation centres or from birds found dead. The comparative morphology of the buzzards sampled in the Cape was determined by constructing a Discriminant Component Analysis using 9 morphometric characters which had previously been established as being important in the separation of Old World Buteo taxa (Kruckenhauser et al., 2004). Blood samples were then analysed using 18 polymorphic microsatellite loci designed for Buteo swainsoni (Hull et al., 2007), using the program STRUCTURE 2.3 to analyse the population assignment of the sampled buzzards. The majority of buzzards were found to most closely match B. trizonatus or B. b. vulpinus in their morphology (52%), and their genetic signature (65%). Additionally, two unidentified genetic signatures were evident. One of these signatures remains unresolved, because buzzards with this genetic signature lacked morphological data. The second signature, however, was displayed by buzzards with larger morphology than is known from both B. b. vulpinus and B. trizonatus. Based on previous research these larger buzzards lay most closely within the morphospace of B. b. menetriesi, being far removed from the morphospace of both B. b. vulpinus and B. trizonatus. Thus, it is conceivable that some of the birds belong to this taxon.
format Thesis
id oai:open.uct.ac.za:11427/15526
institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:32:37.404Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2015
publishDateRange 2015
publishDateSort 2015
publisher Percy FitzPatrick Institute of African Ornithology
publisherStr Percy FitzPatrick Institute of African Ornithology
record_format dspace
source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/15526 The identity, origin and impact of a 'new' buzzard species breeding in South Africa Gwynn, Lisle Amar, Arjun Ornithology South Africa is traditionally known to play host to two taxa of small Buteo, the endemic and uncommon Forest Buzzard B. trizonatus, and Steppe Buzzard B. b. vulpinus, an abundant Palearctic migrant. Since the late 1970s and early 1980s, a number of buzzards appearing unlike B. trizonatus have been found breeding in the south-west Cape, particularly on the Cape Peninsula and in and around the Elgin Valley, ca.60km east of Cape Town. Some of these buzzards resemble B. b. vulpinus, whilst others appear atypical of both B. trizonatus and B. b. vulpinus. This study conducted genetic and morphological analyses on a number of buzzards sampled in the south-west Cape, and compared them with three candidate taxa considered most likely to, in full or in part, explain the identity of these ‘mystery’ buzzards. The candidate taxa were: Steppe Buzzard B. b. vulpinus, Ménétries’s Buzzard B. b. menetriesi and Forest Buzzard B. trizonatus. Morphology data and genetic samples were collected from 23 buzzards through capture with a Bal-Chatri trap, from chicks in nests, from captive birds brought to rehabilitation centres or from birds found dead. The comparative morphology of the buzzards sampled in the Cape was determined by constructing a Discriminant Component Analysis using 9 morphometric characters which had previously been established as being important in the separation of Old World Buteo taxa (Kruckenhauser et al., 2004). Blood samples were then analysed using 18 polymorphic microsatellite loci designed for Buteo swainsoni (Hull et al., 2007), using the program STRUCTURE 2.3 to analyse the population assignment of the sampled buzzards. The majority of buzzards were found to most closely match B. trizonatus or B. b. vulpinus in their morphology (52%), and their genetic signature (65%). Additionally, two unidentified genetic signatures were evident. One of these signatures remains unresolved, because buzzards with this genetic signature lacked morphological data. The second signature, however, was displayed by buzzards with larger morphology than is known from both B. b. vulpinus and B. trizonatus. Based on previous research these larger buzzards lay most closely within the morphospace of B. b. menetriesi, being far removed from the morphospace of both B. b. vulpinus and B. trizonatus. Thus, it is conceivable that some of the birds belong to this taxon. 2015-12-03T14:07:16Z 2015-12-03T14:07:16Z 2015 Master Thesis Masters MSc http://hdl.handle.net/11427/15526 eng application/pdf Percy FitzPatrick Institute of African Ornithology Faculty of Science University of Cape Town
spellingShingle Ornithology
Gwynn, Lisle
The identity, origin and impact of a 'new' buzzard species breeding in South Africa
thesis_degree_str Master's
title The identity, origin and impact of a 'new' buzzard species breeding in South Africa
title_full The identity, origin and impact of a 'new' buzzard species breeding in South Africa
title_fullStr The identity, origin and impact of a 'new' buzzard species breeding in South Africa
title_full_unstemmed The identity, origin and impact of a 'new' buzzard species breeding in South Africa
title_short The identity, origin and impact of a 'new' buzzard species breeding in South Africa
title_sort identity origin and impact of a new buzzard species breeding in south africa
topic Ornithology
url http://hdl.handle.net/11427/15526
work_keys_str_mv AT gwynnlisle theidentityoriginandimpactofanewbuzzardspeciesbreedinginsouthafrica
AT gwynnlisle identityoriginandimpactofanewbuzzardspeciesbreedinginsouthafrica