Sexual selection and genital allometry in the Hottentot golden mole (Amblysomus hottentotus)

Under sexual selection, genitalia typically undergo rapid and divergent evolution across species and competition between the sexes over control of fertilisation may drive the co-evolution of male and female sexual traits. Sexual selection can, therefore, influence genitalia in three fundamental but non-mutually exclusive ways: (1) cryptic female choice, (2) sperm competition and (3) sexual conflict. Golden moles (Chrysochloridae) are a highly specialised family endemic to sub-Saharan Africa. We examined intraspecific genital allometry of both male and female subterranean Hottentot golden moles (Amblysomus hottentotus). Consistent with previous studies in mammals, we found positive allometry and a high coeffi- cient of variation (CV) for male genitalia. The results for female reproductive tract length of A. hottentotus contrast with the findings of previous studies as isometry was recorded. Based on the allometric relationships of both males and females presented here, we suggest that the males do not sequester females and that in the absence of visual cues the female may use penis size as an indicator of phenotypic quality.An honours bursary was awarded to T.A.R from the South African Research Chair Initiative of Mammal Behavioural Ecology and Physiology by the NRF/DST to N.C.B. The research was supported by a National Research Foundation Grant to N.C.B.http://www.elsevier.com/locate /mambiohb2016Mammal Research InstituteZoology and Entomolog

Roan antelope Hippotragus equinus in Africa : a review of abundance, threats and ecology

1. The roan antelope Hippotragus equinus, Africa’s second largest antelope species, is widely distributed throughout Africa. Many populations are isolated, occur at low densities, and are declining. The species’ interactions with and adaptations to the diverse environmental conditions throughout its geographic range remain largely unknown. Most studies have taken place in southern Africa, near the range limit for the species; few studies have been conducted on the historically large Central and West African populations. 2. We reviewed available published and accessible unpublished data related to the ecology of roan antelope. We aim to: 1) review available taxonomic, abundance, distribution, and population trend data; 2) describe the threats faced by the roan antelope, and establish whether sufficient data exist to describe its ecological requirements; and 3) highlight the relevance of conserving this species throughout Africa and suggest where research on survival requirements should be focussed. 3. Roan antelope populations throughout Africa are declining due to natural and anthropogenic threats. Methodological irregularities result in uncertainty and non-comparable population data between studies. Large gaps exist in our knowledge of roan antelope diet and regional movements. Information on the population genetics of roan antelope is needed in order to assess the connectedness of different populations. 4. Data deficiency severely impedes our ability to employ powerful analytical methods aimed at understanding and predicting population persistence and viability, and to model envisaged threats from impending climate change. A unified approach to fundamental ecological research is required to inform the conservation and management of large rare mammalian ungulates such as the roan antelope in Africa.University of Pretoria and South African National Research Foundation.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-29072017-04-30hb2016Mammal Research InstituteZoology and Entomolog

First record of roan antelope (Hippotragus equinus) feeding on the fruits of the sausage tree (Kigelia africana)

No abstract available.National Research Foundation (NRF), Paul G. Allen Family Foundation, Wilderness Safaris, Wilderness Wildlife Trust, Komanis Foundation and Elephants Without Borders.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-20282015-12-30hb201

Benefits of wildlife-based land uses on private lands in Namibia and limitations affecting their development

Legislative changes during the 1960s–1970s granted user rights over wildlife to landowners in southern Africa, resulting in a shift from livestock farming to wildlifebased land uses. Few comprehensive assessments of such land uses on private land in southern Africa have been conducted and the associated benefits are not always acknowledged by politicians. Nonetheless, wildlife-based land uses are growing in prevalence on private land. In Namibia wildlife-based land use occurs over c. 287,000 km2. Employment is positively related to income from ecotourism and negatively related to income from livestock. While 87% of meat from livestock is exported $95% of venison from wildlife-based land uses remains within the country, contributing to food security. Wildlife populations are increasing with expansion of wildlife-based land uses, and private farms contain 21–33 times more wildlife than in protected areas. Because of the popularity of wildlife-based land uses among younger farmers, increasing tourist arrivals and projected impacts of climate change on livestock production, the economic output of wildlife-based land uses will probably soon exceed that of livestock. However, existing policies favour livestock production and are prejudiced against wildlife-based land uses by prohibiting reintroductions of buffalo Syncerus caffer, a key species for tourism and safari hunting, and through subsidies that artificially inflate the profitability of livestock production. Returns from wildlife-based land uses are also limited by the failure to reintroduce other charismatic species, failure to develop fully-integrated conservancies and to integrate black farmers sufficiently.TRAFFIC East/Southern Africa and Tom Milliken for instigating this project and the German Federal Ministry for Economic Cooperation and Development and African Wildlife Conservation Fund.http://journals.cambridge.orgam201

The influence of distance to perennial surface water on ant communities in Mopane woodlands, northern Botswana

Studies of biodiversity along environmental gradients provide information on how ecological communities change in response to biotic and abiotic factors. For instance, distance to water is associated with several factors that shape the structure and the functioning of ecosystems at a range of spatial scales. We investigated the influence of distance to a perennial water source on ant communities in a semi-arid savanna in northern Botswana. Ant abundance, taxonomic richness, and both alpha and beta diversity were generally higher during the wet than the dry season. However, there were strong seasonal influences on the effects of distance to water, with more pronounced effects during the wet season. While both abundance and beta diversity declined with increasing distances to water during the wet season, there was a contrasting increase in alpha diversity. There was no major effect of distance to water on taxonomic richness during either season. Beta diversity was as high across as along gradients, and we found support for modular rather than nested community structures along gradients. Our study demonstrated that small-scale gradients in distance to water can influence several aspects of ant communities in semi-arid savannas. However, our results also point to strong effects of small-scale environmental variation, for instance associated with vegetation characteristics, soil properties, and plant community structure that are not directly linked to water access

Home range and habitat use of roan antelope Hippotragus equinus in Northern Botswana

Studies investigating animal movement and habitat use are essential for wildlife management and conservation. Northern Botswana represents some of the least modified landscapes in Africa. Studying the seasonal habitat use of herbivores in these landscapes provides important baseline information with which to compare the behavioural responses of similar species occurring in anthropogenically modified landscapes. We report on the home range extent and habitat use of roan antelope (Hippotragus equinus) in a region of northern Botswana unaffected by artificial water and fences. We deployed Global Positioning System (GPS) collars on individuals in four roan antelope herds in northern Botswana, three herds in the drier northern section of Botswana and one herd in the wetter Okavango Delta. Herds in the drier northern section occupied larger home ranges (>50 km2) than did herds in the wetter Okavango Delta (<50 km2). All herds preferred specific core areas (all smaller than 20 km2) within their home ranges. All herds had similar location and size of home range between the wet and dry season (non-migratory). All herds occurred in back-country sandveld areas dominated by either Kalahari apple-leaf (Philenoptera nelsii) or silver cluster-leaf (Terminalia sericea) woodlands with low densities of competitors and predators. In Botswana, the long-term persistence of free-roaming roan antelope herds likely depends on the preservation of these unmodified back-country habitats away from permanent water.Wilderness Safaris, the Wilderness Wildlife Trust, the National Research Foundation (NRF) of South Africa, the Research Development Fund of the University of Pretoria, the Botswana Wildlife Management Association (BWMA), the Paul G. Allen Family Foundation, the Conservation Foundation, the Comanis Foundation and Jerome Cohen & Madeleine Delman Cohen.http://www.elsevier.com/locate/jaridenv2022-10-15hj2021Mammal Research InstituteZoology and Entomolog

Data from: The influence of distance to perennial surface water on ant communities in Mopane woodlands, northern Botswana

Studies of biodiversity along environmental gradients provide information on how ecological communities change in response to biotic and abiotic factors. For instance, distance to water is associated with several factors that shape the structure and the functioning of ecosystems at a range of spatial scales. We investigated the influence of distance to a perennial water source on ant communities in a semi-arid savanna in northern Botswana. Ant abundance, taxonomic richness and both alpha and beta diversity were generally higher during the wet than the dry season. However, there were strong seasonal influences on the effects of distance to water, with more pronounced effects during the wet season. While both abundance and beta diversity declined with increasing distances to water during the wet season, there was a contrasting increase in alpha diversity. There was no major effect of distance to water on taxonomic richness during either season. Beta diversity was as high across as along gradients, and we found support for modular rather than nested community structures along gradients. Our study demonstrated that small-scale gradients in distance to water can influence several aspects of ant communities in semi-arid savannas. However, our results also point to strong effects of small-scale environmental variation, for instance associated with vegetation characteristics, soil properties and plant community structure that are not directly linked to water access

Determinants of persistence and tolerance of carnivores on Namibian ranches: implications for conservation on Southern African private lands.

Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where carnivore conservation is being attempted on private lands

Distribution of leopards on commercial farms in Namibia.

<p>Distribution of leopards on commercial farms in Namibia.</p

Correlates of whether Namibian farmers wished to have various species of carnivores on their land (means ± SD) (bold/underlined values are those that were statistically significant (p≤0.05) following a multiple logistic regression.

<p>• Based on low sample sizes (n = 10 respondents provided estimates of livestock losses to lions).</p