Presence and persistence of the Peregrine Falcon and Lanner Falcon in South Africa.

Abstract

The Peregrine Falcon (Falco peregrinus) and the Lanner Falcon (Falco biarmicus) are small to medium-sized birds that display behavioural plasticity to diverse environments and are widely distributed throughout sub-Saharan Africa, where they occur sympatrically. Peregrine Falcons have an almost global distribution, and Lanner Falcons have an Afro-tropical distribution. The aim of this thesis was to determine the presence and persistence of the Peregrine Falcon and the Lanner Falcon across South Africa. This study leverages data from the Southern African Bird Atlas Project (SABAP1 and SABAP2), social media platforms (Facebook®, eBird®, and iNaturalist®), and literature (sourced from Google Scholar®, Web of Science®, Scopus®, and PUBMED®) to investigate the distribution and relative abundance of the Peregrine Falcon and Lanner Falcon across South Africa. Both species, often coexisting across sub-Saharan Africa, share similar habitat preferences and prey species selection. Peregrine Falcons’ behavioural plasticity to urban environments highlights its resilience, whereas Lanner Falcons displayed mixed responses suggesting targeted conservation strategies to mitigate the impacts of habitat fragmentation, land use changes, and urban encroachment. Peregrine Falcons had a more restricted distribution within South Africa than Lanner Falcons, and both species had distributions within urban areas. The presence of Peregrine Falcons negatively influenced Lanner Falcons distributions and abundance. Lanner Falcons were more frequently observed but remained understudied in comparison. Overall, both species are understudied in Africa, particularly in South Africa. Research on both falcons focussed on their breeding ecology and the health of the species with a focus on egg-shell thickness in response to environmental factors and parasitic studies. Research was primarily based in Europe and North America, and both species remain understudied in other regions of geographical distribution. Research techniques for monitoring and data collection relied on observational data and biological and genetic sampling. Established monitoring techniques are commonly used, and new novel approaches such as citizen science remain underutilised but with growing interest. The findings in this thesis highlight the complex relationship between urbanisation, species competition, social interactions, ecology, behaviour, and habitat preferences in shaping these falcons' distribution and population trends.