No abstract

No abstract

Summary 1. Seasonality of rainfall can exert a strong influence on animal condition and on host-parasite interactions. The body condition of ruminants fluctuates seasonally in response to changes in energy requirements, foraging patterns and resource availability, and seasonal variation in parasite infections may further alter ruminant body condition. 2. This study disentangles effects of rainfall and gastrointestinal parasite infections on springbok (Antidorcas marsupialis) body condition and determines how these factors vary among demographic groups. 3. Using data from four years and three study areas, we investigated i) the influence of rainfall variation, demographic factors and parasite interactions on parasite prevalence or infection intensity, ii) whether parasitism or rainfall is a more important predictor of springbok body condition and iii) how parasitism and condition vary among study areas along a rainfall gradient. 4. We found that increased parasite intensity is associated with reduced body condition only for adult females. For all other demographic groups, body condition was significantly related to prior rainfall and not to parasitism. Rainfall lagged by two months had a positive effect on body condition. 5. Adult females showed evidence of a “periparturient rise” in parasite intensity, and had higher parasite intensity and lower body condition than adult males after parturition and during early lactation. After juveniles were weaned, adult females had lower parasite intensity than adult males. Sex differences in parasitism and condition may be due to differences between adult females and males in the seasonal timing of reproductive effort and its effects on host immunity, as well as documented sex differences in vulnerability to predation. 6. Our results highlight that parasites and the environment can synergistically affect host populations, but that these interactions might be masked by their interwoven relationships, their differential impacts on demographic groups, and the different time scales at which they operate.

Connectivity conservation is aimed at sustaining animal movements and ecological processes important to ecosystem functioning and the maintenance of biodiversity. However, connectivity conservation plans are typically developed around a single species and rarely empirically evaluated for their relevance to others, thereby limiting our understanding of how connectivity requirements differ across species. We used an omnidirectional application of circuit theory and GPS data from six species to evaluate connectivity at multiple scales for multiple species within the world's largest transfrontier conservation landscape in southern Africa. We evaluated the effects of linear barriers, natural habitat types and anthropogenic land use on movement. We identified multispecies connectivity hotspots as areas where current flow was concentrated or channelled through pinch points. To evaluate surrogate species for connectivity, we evaluated the correspondence among single‐species connectivity across the entire landscape and also examined whether a more localized corridor for African savanna elephant Loxodonta africana captured high multispecies connectivity values. Connectivity models revealed many intact areas across the landscape with diffuse current flow, but also evidence that fences, rivers, roads and areas of anthropogenic use acted as strong barriers to movement—particularly in the case of fences, which completely blocked female elephant movement. Tests of correspondence among single‐species connectivity models revealed spotted hyaena and African wild dog as the strongest surrogate species of connectivity. Female elephants were found to be the weakest surrogate species of connectivity at the landscape scale. However, focusing within a localized elephant corridor revealed the areas of concentrated or channelled connectivity for most species in our study. Synthesis and applications. Our results suggest that the single‐species focus permeating connectivity literature may result in conservation plans that poorly conserve the connectivity needs of co‐occurring species. Our study also highlights the importance of testing the efficacy of surrogate species for connectivity at multiple scales. We recommend evaluating multispecies connectivity to prioritize areas for conservation that safeguard the connectivity needs of multiple species of conservation concern.