Dynamics of direct inter-pack encounters in endangered African wild dogs

Aggressive encounters may have important life history consequences due to the potential for injury and death, disease transmission, dispersal opportunities or exclusion from key areas of the home range. Despite this, little is known of their detailed dynamics, mainly due to the difficulties of directly observing encounters in detail. Here, we describe detailed spatial dynamics of inter-pack encounters in African wild dogs (Lycaon pictus), using data from custom-built high-resolution GPS collars in 11 free-ranging packs. On average, each pack encountered another pack approximately every 7 weeks and met each neighbour twice each year. Surprisingly, intruders were more likely to win encounters (winning 78.6% of encounters by remaining closer to the site in the short term). However, intruders did tend to move farther than residents toward their own range core in the short-term (1 h) post-encounter, and if this were used to indicate losing an encounter, then the majority (73.3%) of encounters were won by residents. Surprisingly, relative pack size had little effect on encounter outcome, and injuries were rare (<15% of encounters). These results highlight the difficulty of remotely scoring encounters involving mobile participants away from static defendable food resources. Although inter-pack range overlap was reduced following an encounter, encounter outcome did not seem to drive this, as both packs shifted their ranges post-encounter. Our results indicate that inter-pack encounters may be lower risk than previously suggested and do not appear to influence long-term movement and ranging

Effects of body size on estimation of mammalian area requirements

Accurately quantifying species’ area requirements is a prerequisite for effective area‐based conservation. This typically involves collecting tracking data on species of interest and then conducting home‐range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home‐range areas with GPS locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4,000 kg. We then applied block cross‐validation to quantify bias in empirical home‐range estimates. Area requirements of mammals 1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum

Emerging technology to measure habitat quality and behavior of grouse: Examples from studies of greater sage-grouse

An increasing number of threats, both natural (e.g. fires, drought) and anthropogenic (e.g. agriculture, infrastructure development), are likely to affect both availability and quality of plants that grouse rely on for cover and food. As such, there is an increasing need to monitor plants and their use by grouse over space and time to better predict how changes in habitat quality influence the behavior of grouse. We use the greater sage-grouse Centrocercus urophasianus to showcase how new technology can be used to advance our understanding of the ecology, behavior and conservation of grouse. We demonstrate how laser, spectral and chemical detectors and unmanned aerial systems can be used to measure structural and phytochemical predictors of habitat quality at several spatial scales. We also demonstrate how advanced biotelemetry systems and robotic animals can be used to measure how habitat quality influences fine-scale habitat use, movement and reproductive effort of grouse. Integrating these technologies will allow researchers to better assess and manage the links among habitat quality (safety and food), resource acquisition (foraging behavior) and reproductive behaviors of grouse

Parentage analysis in a managed free ranging population of southern white rhinoceros: genetic diversity, pedigrees and management

Small populations are vulnerable to the consequences of breeding within closed groups as the loss of genetic variability can lead to inbreeding depression. Here, we use microsatellite genotypes to assess variability and parentage within a small, managed population of southern white rhinoceros in northern Namibia. Tissue samples gathered from either a modified biopsy darting technique or ear notches allowed us to obtain genotypic data for all individuals in the population. As expected for this species, genetic variability in the population was relatively low (overall H obs 0.45). In combination with detailed management records for the period 1993–2009, we were able to assign both parents for all 23 offspring. Only one calf of seven in the F2 generation arose from father–daughter inbreeding within the population. Our analysis revealed that paternity was initially dominated by a single founder bull siring 10 of 13 calves over 9 years; paradoxically, the other founder bull was selected for removal based on observations suggesting he was behaviourally dominant and therefore the likely sire of most calves. We also found that young introduced bulls were breeding successfully within 6 months of their arrival, well before having established their home ranges. We argue that in order to optimally manage and conserve the southern African white rhinoceros meta-population it is essential to have accurate pedigree information and genetic data for all individuals in the numerous small populations that are key to the survival of the species.Ongava Research Centre is funded by charitable donations from the Namibian Wildlife Conservation Trust (UK), West Midlands Safari Park (UK) and the Directors of Ongava Game Reserve.http://link.springer.com/journal/10592hb201