Cooper, Tessa June Groves.
The effects of land use changes on the distribution of forest dependent bird species in South Africa.
Degree: MSc, Botany and Zoology, 2015, Stellenbosch University
ENGLISH ABSTRACT: Forests in South Africa have had a long history of human utilization and disturbance, and are under threat from a variety of anthropogenic land use changes. Foremost of these are deforestation and forest degradation, impacting the species native to these forests. The aims of this study were to determine changes in the distribution of forest dependent bird species according to the South African Bird Atlas Project; to relate these changes to changes in land-use; to identify links between these changes; to determine the extent, location and causes of the decline of each forest dependent bird species; and to identify current risks to forest dependent bird species in South Africa. Range data on 57 forest dependent bird species from SABAP1 (1987-1992) and SABAP2 (2007-present) were analyzed. Of these, 28 species were found to have declining ranges. Thirty sites across South Africa were identified as being most at risk, with all having experienced a loss of more than 10 of the 57 forest dependent bird species between SABAP1 and SABAP2. The range change data of the 28 species with decreasing ranges were correlated with data on changes in land cover over the same time period to infer relationships between changes in land use and change in bird ranges. Occupancy modelling was done to determine which land cover types affect extinction and initial presence. Individual species characteristics were analyzed to determine links between characteristics and response to land use change. A pan-European trait-based risk assessment framework was applied to all 57 species to identify habitats and species most at risk, as well as the most important threats to species persistence. Results showed that natural vegetation decreased in 67% of sites, while plantations and cultivation increased in 50% of sites. Occupancy modelling showed extinction likelihood to increase with plantations in some species, while plantations mitigated extinction likelihood in other species. Urbanization and cultivation likewise mitigated extinction likelihood in some species. Natural vegetation was replaced by cultivation, while cultivation was replaced by urbanization. The number of species lost increased with a loss of natural vegetation. Twenty two of the thirty sites experienced deforestation of indigenous forests between 2000 and 2013/2014; changes in natural vegetation in these sites can be attributed primarily to deforestation, and a loss of plantations. While most at-risk sites were in the Eastern Cape, there was no geographic grouping of species loss or of land use change. Most species lost were birds of prey or insectivores, and species characteristics and habitat preferences determined the sites from which they were lost. The Cape parrot (Poicephalus robustus), rufous-chested sparrowhawk (Accipiter rufiventris) and the migratory Eurasian golden oriole (Oriolus oriolus) suffered the largest declines in range size and are thought to be most at risk. Montane forests were found to be more at risk than other forest types. The major risks…
Advisors/Committee Members: Cherry, Michael I., Wannenburgh, Andrew, Stellenbosch University. Faculty of Science. Dept. of Botany and Zoology..
Subjects/Keywords: Forest dependent bird species; Birds – Ecology; Birds – Deforestation; Land use change; UCTD
to Zotero / EndNote / Reference
APA (6th Edition):
Cooper, T. J. G. (2015). The effects of land use changes on the distribution of forest dependent bird species in South Africa. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/97842
Chicago Manual of Style (16th Edition):
Cooper, Tessa June Groves. “The effects of land use changes on the distribution of forest dependent bird species in South Africa.” 2015. Masters Thesis, Stellenbosch University. Accessed November 12, 2019.
MLA Handbook (7th Edition):
Cooper, Tessa June Groves. “The effects of land use changes on the distribution of forest dependent bird species in South Africa.” 2015. Web. 12 Nov 2019.
Cooper TJG. The effects of land use changes on the distribution of forest dependent bird species in South Africa. [Internet] [Masters thesis]. Stellenbosch University; 2015. [cited 2019 Nov 12].
Available from: http://hdl.handle.net/10019.1/97842.
Council of Science Editors:
Cooper TJG. The effects of land use changes on the distribution of forest dependent bird species in South Africa. [Masters Thesis]. Stellenbosch University; 2015. Available from: http://hdl.handle.net/10019.1/97842