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Management and conservation rely on surveys to determine which species are present but some species, such as nocturnal mammals, can be very difficult to detect. Camera trapping, driven transects, and ad hoc records are well-established nocturnal survey methods, but their detection effectiveness has not been tested against known species presence. We tested the effectiveness of these methods with a known assemblage of nocturnal African mammals. We compared camera traps placed at targeted and random locations, driven transects, and informal ad hoc records against one another and the 20 predominately nocturnal medium- and large-sized mammals known to be on site. Species-specific detection patterns, detection curves for each method, and detection effort required per species, were compared to determine the effectiveness of each method. Each of the methods detected at least 60% of known nocturnal mammal species over a 20-month period: driven transects and ad hoc records were the most successful (16/20 80%), followed by targeted camera traps (15/20 75%) and random camera traps (12/20 60%). Jaccard’s Coefficients of Community Similarity peaked at 0.78, showing notable differences in the communities sampled with different methods. There was considerable variation in effort required to detect each species for each method, and the number of species detected with specific levels of effort was also highly variable between methods. We suggest that mixing methods, using different camera placement including use of random locations, and incorporating cost-neutral ad hoc records into formal survey efforts can all greatly increase the overall effectiveness and efficiency of species detection.

In many social species physical attributes correlate with dominance rankings and influence the outcomes of dyadic interactions. We investigated the processes that affect white rhinoceros’ social behaviour in response to a reduction in horn size asymmetries within a group of subadult individuals. We monitored agonistic social interactions and the orderliness of social rankings between six free ranging rhinoceroses before and after they underwent a second dehorning procedure. We used a modified version of Landau’s h’ to measure linearity, a score of steepness to measure power asymmetry, and a measure of triangle transitivity to assess relationships in the presence of null dyads. Agonistic social interactions were significantly greater after the monitored dehorning procedure. Hierarchies possessed significant steepness and transitivity prior to the procedure, but not after. Linearity was non-significant and rank order did not correspond with changes in horn size or age. Our results provide the first evidence of a dominance hierarchy among free-ranging white rhinoceroses outside of reproductive competition, but indicate that physical attributes alone do not explain social rankings. Rhinoceroses transitioned to a more egalitarian dominance structure than a despotic one after the procedure, but dominance ranks were only weakly differentiated within the group. Although a reduction in horn asymmetries may increase agonistic behaviours via psychosocial or behavioural changes, drier climatic conditions cannot be ruled out as the causative factor and because the subadult group stayed together, rather than dispersing, any increased fitness costs are likely to be minimal and outweighed by the benefits of group membership.

Ticks are obligate blood-feeding ectoparasites that have negative effects on animals through blood loss and vectoring disease. Controlling ticks is a major aspect of wildlife management in many areas, including African savannah where ticks are a long-standing problem. Rotational burning of vegetation is widely thought to reduce ticks but empirical data are lacking. We investigate the effect of block rotational burning on tick populations in a South African wildlife reserve. We measured tick presence/abundance using tick drags in multiple blocks of five different burn ages (areas burned 1, 2, 3, 4 or 5 years previously). We also assessed herbivore diversity using dung as a proxy. Tick presence was highest in areas burned 2–3 years previously. It was lowest in recently-burned areas (probably due to fire-induced mortality or loss of field-layer refugia) and areas burned = 4 years previously (probably because the lack of palatable grass meant herbivore abundance was lower; this is supported by significantly lower herbivore presence in old burns and significant positive correlation between tick numbers and herbivore presence). Burn age and, to a lesser extent, block, were significantly related to tick presence and abundance at both larval and nymph stages. The model that best explained tick numbers, though, included the interaction between burn age and block due to substantial inter-block variability in mid-burn blocks relative to lower variability in blocks at the start or end of the burn cycle. This suggests that burn age and block-specific conditions together influence tick abundance, with habitat heterogeneity likely being an important modifier of the effect burning has on tick numbers. Although annual burning of large areas would not be feasible while maintaining suitable grazing, we suggest that additional annual burning of potential wildlife (and therefore tick) hotspots, such as around waterholes, could reduce tick populations and improve wildlife management.