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The increased rate of human-driven change is a major threat to biodiversity. Although there is sufficient evidence to suggest that species notably alter their ranges, facilitation of such movement for larger vertebrate species often places burdens on management agencies. Oribi antelope (Ourebia ourebi ourebi) in South Africa continue to experience dramatic decreases in range and numbers. Animals have and continue to be translocated for conservation, but also aesthetic and financial reasons. Initial translocations were done in the absence of any thought or understanding of genetic structure, while for the past two decades a conservative best-practice approach was adopted, but in the absence of any specific genetic information. Here, we use two mitochondrial and one nuclear fragment to report the phylogeographic structure in oribi antelope across South Africa. Our data indicate that the South African subspecies is distinct from other subspecies to the north, confirming that oribi in South Africa should be managed as a distinct conservation unit. Across the South African range, high genetic diversity is present with some evidence for genetic structure (phylogenetic trees and haplotype networks). However, there is no spatial component to the diversity (non-significant p-values in AMOVA analyses), possibly because of historic translocations. We evaluate translocation approaches currently in place, and make specific and general recommendations for future conservation management based on an improved understanding of population genetic diversity and genetic structure.
The modification of natural habitats requires behavioural plasticity, which may be challenging for ‘specialist’ species. Quantifying habitat requirements and behavioural responses of specialists to landscape transformation is thus a priority for baseline data to inform conservation practices. Using camera-trap surveys of the forest-dependent Lemon Dove Aplopelia larvata in conjunction with detailed microhabitat-scale covariates, we assessed habitat use during two periods in the year: autumn—winter and spring—summer (which largely encompassed peak breeding). We used occupancy modelling of forest-structural covariates to produce models of the probability of occupancy and detection of Lemon Doves in patches of the Indian Ocean Coastal Belt Forest of South Africa. The average occupancy and detection probability as indicated by the top-performing models was 0.39 ± 0.08 and 0.26 ± 0.05, respectively, during autumn—winter, and 0.37 ± 0.08 and 0.25 ± 0.04, respectively, during spring—summer. Although occupancy and probability of detection remained relatively constant between seasons, there was seasonal variation in the influence of individual covariates for both measures. The overall trend of positive influences on Lemon Dove occupancy was that of complex and diverse habitat structures and high plant species richness. The specific covariates that influenced occupancy positively during spring—summer may reflect the ecological requirements for nestling provisioning for both dietary needs and an avoidance of potential disturbance. Thus, while Lemon Doves may be less habitatspecific during autumn—winter, conservation management plans for safeguarding the breeding success of the species are advised to ensure adequate protection of large forest patches with complex and diverse interior structures and minimal disturbance.
Fenthion is a widely used organophosphorus pesticide in agriculture that induces different cytotoxic effects, including male reproductive toxicity. The present work aimed to study the ameliorative effects of curcumin, a potential therapeutic agent against several chronic diseases, on reproductive toxicity induced by the organophosphate insecticide fenthion. Forty adult male albino rats were divided into four groups. The control group received distilled water. The curcumin group was administered curcumin at a dose of 100 mg kg−1 body weight. The fenthion group was administered fenthion at a dose of 0.001 mg kg−1. The fenthion/curcumin group was administered fenthion and curcumin together at the same doses. After four weeks of daily oral administration, the animals were sacrificed and their testes were excised. Specimens were processed for histopatholological and immunohistochemical investigations. Light and electron microscopic analysis visualised dramatic degenerative changes in seminiferous tubules as indicated by atrophy, necrosis, vacuolation and decreased number of spermatogenic cells. Moreover, the fenthion group showed a significant reduction in the proliferating cell nuclear antigen (PCNA)-immunoreactivity. Decreased PCNA-immunoreactivity reflected the depletion in the proliferation rate of spermatogenic cells and suggesting arrested spermatogenesis. Curcumin administration to fenthion-treated rats revealed mild degenerative changes with partial improvement of active spermatogenesis. In conclusion, these data may confirm the cytoprotective potency of curcumin against fenthion-induced cyto-toxicity.
Fences are utilised throughout the world to restrict the movements of wildlife, protecting them from threats and reducing human—wildlife conflict. In South Africa the number of privately-owned fenced game reserves has greatly increased in recent years, but little is known about how fencing affects the distribution and movements of target and non-target mammals. We surveyed 2 m either side of the complete fence line of a recently established commercial game reserve in South Africa, identifying signs of animal presence (spoor, scat, foraging or other field signs) while also recording damage (holes) to the fence. Every 250 m we carried out 100 m perpendicular transects either side of the fence, recording vegetation cover and height at 10 m intervals along the transect. We found that livestock (largely cattle) were excluded from the reserve. However, 12% of records of large animal species were recorded outside of the fence line. These species had been introduced to the reserve, strongly suggesting that they had crossed the boundary into the surrounding farmland. Sixteen naturally present wild species were found on both sides of the fence, but we found more evidence of their presence inside the reserve. Observational evidence suggests that they were regularly crossing the boundary, particularly where the fence was damaged, with hole size affecting species recorded. We also found evidence that the construction of the fence had led to a difference in vegetation structure with plant richness and percentage of non-woody plant cover significantly higher inside the fence. While fencing was highly effective at preventing movement of livestock, introduced and wild animals were able to cross the boundary, via holes in the fence. This work shows that the efficacy of the most common approach to preventing animal movement around protected areas depends on the species being considered and fence condition.
Two recent studies have suggested that divergent mitochondrial lineages may be present within spirostreptid genera such as BicoxidensAttems, 1928. Bicoxidens, similar to many other endemic soil invertebrates, exhibits low dispersal capabilities and strict microclimate habitat preferences, attributes that often lead to geographic isolation. Given that prolonged geographic isolation often lays the foundation for population genetic differentiation, genetic divergence and possibly speciation, there was good reason to suspect that Bicoxidens may consist of several distinct lineages. On this basis, the mitochondrial cytochrome c oxidase subunit 1 (COI) was used to reconstruct the phylogeny of Bicoxidens and reveal divergent lineages within the genus. Maximum likelihood and Bayesian inference analyses recovered a paraphyletic Bicoxidens phylogram with divergent lineages present in three species — B. friendi, B. flavicollis and B. brincki — suggesting high genetic diversity within the genus. Bayesian genetic cluster analyses suggested the presence of multiple distinct mitochondrial lineages within the genus with four identified in B. flavicollis alone. It was therefore concluded that the divergent lineages observed among Bicoxidens populations may suggest the presence of hidden species.
Parasites are an important but neglected component of ecosystems that can be used as indicators of host biology and ecology. In the present study, the metazoan parasite assemblage of Ruvettus pretiosus, an understudied but widely distributed predatory gempylid, caught off South Africa was surveyed. A total of seven parasite taxa, including four new infection records (Bolbosoma capitatum, Rhadinorhynchus sp., Hepatoxylon trichiuri and Anisakis sp.), two new locality records (B. capitatum and Rhipidocotyle sp.) as well as the ectoparasitic copepod Sagum foliaceus and the cestode Tentacularia coryphaenae were recovered from the eight specimens examined.
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