Influence of historical and contemporary habitat changes on the population genetics of the endemic South African parrot Poicephalus robustus

2019 ◽  
Vol 30 (2) ◽  
pp. 236-259
Author(s):  
WILLEM G. COETZER ◽  
COLLEEN T. DOWNS ◽  
MIKE R. PERRIN ◽  
SANDI WILLOWS-MUNRO

SummaryThe Cape Parrot Poicephalus robustus is a habitat specialist, restricted to forest patches in the Eastern Cape (EC), KwaZulu-Natal (KZN) and Limpopo provinces of South Africa. Recent census estimates suggest that there are less than 1,600 parrots left in the wild, although historical data suggest that the species was once more numerous. Fragmentation of the forest biome is strongly linked to climate change and exploitation of the forest by the timber industry. We examine the subpopulation structure and connectivity between fragmented populations across the distribution of the species. Differences in historical and contemporary genetic structure of Cape Parrots is examined by including both modern samples, collected from 1951 to 2014, and historical samples, collected from 1870 to 1946. A total of 114 individuals (historical = 29; contemporary = 85) were genotyped using 16 microsatellite loci. We tested for evidence of partitioning of genotypes at both a temporal and spatial scales by comparing shifts in allelic frequencies of historical (1870–1946) and contemporary (1951–2014) samples across the distribution of the species. Tests for population bottlenecks were also conducted to determine if anthropogenic causes are the main driver of population decline in this species. Analyses identified three geographically correlated genetic clusters. A southern group restricted to forest patches in the EC, a central group including birds from KZN and a genetically distinct northern Limpopo cluster. Results suggest that Cape Parrots have experienced at least two population bottlenecks. An ancient decline during the mid-Holocene (∼ 1,800-3,000 years before present) linked to climate change, and a more recent bottleneck, associated with logging of forests during the early 1900s. This study highlights the effects of climate change and human activities on an endangered species associated with the naturally fragmented forests of eastern South Africa. These results will aid conservation authorities with the planning and implementation of future conservation initiatives. In particular, this study emphasises the Eastern Cape mistbelt forests as an important source population for the species and calls for stronger conservation of forest patches in South Africa to promote connectivity of forest taxa.

Koedoe ◽  
2015 ◽  
Vol 57 (1) ◽  
Author(s):  
Graham R.H. Grieve ◽  
Colleen T. Downs

Eastern mistbelt forests are naturally fragmented forests with grassland which occur from the Eastern Cape to KwaZulu-Natal, South Africa. These were heavily logged by colonial settlers and continue to be harvested despite being protected. Consequently we documented a checklist of the plants of the forests and grasslands in the Weza district (3029DA WEZA), southern KwaZulu-Natal, including Ngeli Forest and nearby indigenous forest patches to highlight their biodiversity status and need for conservation. We also reviewed their status in the Red Data List. Of the 1554 records included in this summary of plant species for the Weza district, there were 6 lichens (0.4%), 46 bryophytes (3.0%), 58 pteridophytes (3.7%), 6 gymnosperms (0.4%) and the remaining 1424 species angiosperms (92.5%). Of the angiosperms, 27.3% were monocotyledons and 72.7% were dicotyledons. The most species-rich family was Asteraceae (239 species) followed by Fabaceae (115 species), Liliaceae (used for purposes of comparison against older studies – 89 species), Orchidaceae (89 species), Iridaceae (59 species), Poaceae (58 species), Asclepidaceae (again used for purposes of comparison against older studies – 57 species), Scrophulariaceae (42 species), Euphorbiaceae (32 species), Lamiaceae (32 species) and Rubiaceae (27 species). These 10 families each comprised more than 2% of the species in the list. Together they contributed 55% of the angiosperm species and 34.1% of the angiosperm genera. The biodiversity and conservation value of the study area are conserved pockets of eastern mistbelt forest, Drakensberg foothill moist grassland and mistbelt grassland. More than 4% of the species are under some degree of threat, as was evidenced by the number of species regarded as endangered (5), vulnerable (18), near threatened (10), critically rare (1), rare (20) or declining (11) amongst the 1554 species covered in the list.Conservation implications: In terms of taxa under some degree of threat, number of endemic and near endemic species the biodiversity and conservation value of the Ngele (3029DA WEZA) area is reinforced. This necessitates that the area is appropriately protected from invasive alien species, and uncontrolled and illegal use by the neighbouring communities.


2018 ◽  
Vol 10 (12) ◽  
pp. 2055 ◽  
Author(s):  
Catherine Van den Hoof ◽  
Michel Verstraete ◽  
Robert Scholes

Grasslands, which represent around 40% of the terrestrial area, are mostly located in arid and semi-arid zones. Semiarid ecosystems in Africa have been identified as being particularly vulnerable to the impacts of increased human pressure on land, as well as enhanced climate variability. Grasslands are indeed very responsive to variations in precipitation. This study evaluates the sensitivity of the grassland ecosystem to precipitation variability in space and time, by identifying the factors controlling this response, based on monthly precipitation data from Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) and the Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) data from the Multi-angle Imaging SpectroRadiometer-High Resolution (MISR-HR) datasets, used as proxy for productivity, at 60 grassland sites in South Africa. Our results show that MISR-HR products adequately capture the spatial and temporal variability in productivity at scales that are relevant to this study, and they are therefore a good tool to study climate change impacts on ecosystem at small spatial scales over large spatial and temporal domains. We show that combining several determinants and accounting for legacies improves our ability to understand patterns, identify areas of vulnerability, and predict the future of grassland productivity. Mean annual precipitation is a good predictor of mean grassland productivity. The grasslands with a mean annual rainfall above about 530 mm have a different functional response to those receiving less than that amount of rain, on average. On the more arid and less fertile soils, large inter-annual variability reduces productivity. Our study suggests that grasslands on the more marginal soils are the most vulnerable to climate change.


2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yanga Simamkele Diniso ◽  
Leocadia Zhou ◽  
Ishmael Festus Jaja

Purpose This study aims to evaluate the knowledge and attitudes of dairy farmers about climate change in dairy farms in the Eastern Cape province of South Africa. Design/methodology/approach The study was conducted following a cross-sectional research design (Bryman, 2012). The study was conducted mainly on dairy farms located on the south-eastern part of the Eastern Cape province in five districts out of the province’s six districts (Figure 1). These districts include Amathole, Chris Hani, OR Tambo and Cacadu; these regions were not included in a recent surveying study (Galloway et al., 2018). Findings In all, 71.7% of dairy farm workers heard about climate change from the television, and 60.4% of participants reported that they gathered information from radio. Eighty-two out of 106 (77.4%) correctly indicated that climate change is a significant long-term change in expected weather patterns over time, and almost 10% of the study participants had no clue about climate change. Approximately 63% of the respondents incorrectly referred to climate change as a mere hotness or coldness of the day, whereas the remainder of participants correctly refuted that definition of climate change. Most of the study participants correctly mentioned that climate change has an influence on dairy production (92.5%), it limits the dairy cows’ productivity (69.8%) and that dry matter intake of dairy cows is reduced under higher temperatures (75.5%). Research limitations/implications The use of questionnaire to gather data limits the study, as respondents relied on recall information. Also, the sample size and study area limits use of the study as an inference for the excluded parts of the Eastern Cape Province. Also, it focused only on dairy farm workers and did not request information from beef farmers. Practical implications This study imply that farmers without adequate knowledge of the impact of climate change keep complaining of a poor yield/ animal productivity and changing pattern of livestock diseases. Hence, a study such as the present one helps to bridge that gap and provide relevant governing authority the needed evidence for policy changes and intervention. Social implications Farmers will begin to get help from the government regarding climate change. Originality/value This a first study in South Africa seeking to document the knowledge of dairy farm workers about climate change and its impacts on productivity.


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