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It is commonly assumed that larger species are more vulnerable to extinction because of their low population densities and slow time to recover from setbacks. We report that, contrary to this expectation, it is the smaller ungulate species that first reached the brink of local extirpation within a 950 km 2 fenced protected area, the Hluhluwe-iMfolozi Park. Moreover, earlier records show that most of these species had formerly been extremely common within the park region. Neither habitat change, competition for resources or exposure to predation provided a consistent sole explanation for the drastic population crashes shown by five smaller ungulate species (body mass 10–45 kg). We suggest that smaller species can be more vulnerable to local extinction as a consequence of their narrower habitat occupation and hence restricted spatial distribution. Nevertheless all of the threatened species thrive widely outside the protected area. Our findings show that smaller rather than larger species can be most at risk of local extirpation when confined within protected areas. Hence more attention needs to be given to conserving such species within broader regional landscapes. [ABSTRACT FROM AUTHOR]

There is a growing theoretical basis for the role of predation risk as a driver of trophic interactions, conceptualized as the 'ecology of fear'. However, current ungulate management ignores the role of nonlethal risk effects of predation., We introduce the concept of 'hunting for fear' as an extension of the more classical 'hunting to kill' that is typically used in large herbivore management. Hunting for fear aims to induce a behavioural response in ungulates, for example, as a way of diverting them from areas where their impact is undesired., Synthesis and applications. Hunting for fear asks for novel, potentially controversial, ways of hunting to induce strong enough risk effects, including more hunting on foot and with dogs, extended hunting seasons (ideally year-round) and increased hunting of calves. Hunting for fear may offer novel opportunities to help manage the growing human-wildlife conflicts that we experience globally. [ABSTRACT FROM AUTHOR]

Abstract: Browsing lawns, as an analogue of the influential grazing lawn concept, received increased recent interest. We revisit this concept and ask whether the underlying characteristics of a grazing lawn can indeed be generalized to browser–woody plant interactions. Based on previous studies, we define a lawn as a grazed or browsed patch in which intense foraging leads to increased resource availability and a proportional increase of palatable plant species in the patch. We then argue that present examples do not fully support a browsing lawn analogue. Although intense browsing can lead to increased resource availability, it generally reduces the share of palatable plant species in the community. We present an example that does seem to fit both lawn conditions; intensely browsed regeneration patches of palatable trees in Białowieża Primeval forest. Browsing not only prunes these regeneration patches into lawn-like structures, but also increases the share of palatable species in the tree community. Finally, we outline key open issues of the browsing lawn analogue and discuss the discrepancy between our example and the general understanding that browsing reduces the share of palatable tree species. We suggest that lawns are most likely to develop in relatively resource-rich environments where plants can invest in tolerance traits and in situations where herbivores show strong patch selection but are relatively unselective for individual plants within the patch. Although our example fits these conditions, many studies on browser–woody plant interactions come from relatively nutrient poor systems with strong selection for individual palatable trees. More studies in systems similar to our example might show that positive interactions between browsing and the proportion of palatable woody species in a community are not so rare. [Copyright &y& Elsevier]

A study was undertaken, modeling Black rhino, Diceros bicornis, populations from Hluhluwe-Umfolozi Game Reserve and Mkuzi Game Reserve, Republic of South Africa. This study had two specific goals. Firstly, we tried to find a simple model to predict the population number in the following year and give insight in the number of animals that can be removed from the population. Secondly, the use of different models gave us the opportunity to evaluate the effect of small differences in model structure on the outcome of the models. Five different models were tested, mainly focusing on the structure of density dependence. The density dependent model, that incorporated stronger density dependence at high densities, fitted best to the observed census values. The study, furthermore, indicated that the population in Hluhluwe-Umfolozi is stabilizing. The situation in Mkuzi was not that clear. Based on these results, managers should therefore be more careful with removing animals from this population. Finally the results clearly showed that different model structures can result in very different model outcomes. Besides in the values of the model parameters, this was also shown by different values for the population number where the yearly increase is maximal. Based on these results it does not seem wise to base management decisions solely on the outcome of one model. Therefore, we strongly encourage managers to compare the outcome from different model structures, based on different biological assumptions. [Copyright &y& Elsevier]

Summary The loss of apex consumers (large mammals at the top of their food chain) is a major driver of global change [ 1 ]. Yet, research on the two main apex consumer guilds, large carnivores [ 2 ] and megaherbivores [ 3 ], has developed independently, overlooking any potential interactions. Large carnivores provoke behavioral responses in prey [ 1, 4 ], driving prey to distribute themselves within a “landscape of fear” [ 5 ] and intensify their impacts on lower trophic levels in low-risk areas [ 6 ], where they may concentrate nutrients through localized dung deposition [ 7, 8 ]. We suggest, however, that megaherbivores modify carnivore-induced trophic cascades. Megaherbivores (>1,000 kg [ 9 ]) are largely invulnerable to predation and should respond less to the landscape of fear, thereby counteracting the effects of fear-triggered trophic cascades. By experimentally clearing plots to increase visibility and reduce predation risk, we tested the collective role of both apex consumer guilds in influencing nutrient dynamics in African savanna. We evaluated whether megaherbivores could counteract a behaviorally mediated trophic cascade by redistributing nutrients that accumulate through fear-driven prey aggregations. Our experiment showed that mesoherbivores concentrated fecal nutrients in more open habitat, but that megaherbivores moved nutrients against this fear-driven nutrient accumulation by feeding within the open habitat, yet defecating more evenly across the risk gradient. This work adds to the growing recognition of functional losses that are likely to have accompanied megafaunal extinctions by contributing empirical evidence from one of the last systems with a functionally complete megaherbivore assemblage. Our results suggest that carnivore-induced trophic cascades work differently in a world of giants. [ABSTRACT FROM AUTHOR]

Questions How is woody vegetation patchiness affected by rainfall, fire and large herbivore biomass? Can we predict woody patchiness and cover over large-scale environmental gradients? Location Hluhluwe- iMfolozi Park, South Africa. Methods We quantified variation in local patchiness as the lacunarity of woody cover on satellite-derived images. Using Random Forest regression we analysed how both average woody cover and its patchiness depend on annual rainfall, fire frequency and grazer and browser metabolic biomass densities. Results Fire frequency and rainfall were the clearest predictors, whereas effects of large herbivores on woody vegetation were smaller and more complex. Under low rainfall conditions (500 mm·yr−1) trees had less total cover and were more regularly spaced across the landscape (lower patchiness). Woody cover and vegetation patchiness increased with rainfall whereas fire frequency decreased woody cover and further increased patchiness. Conclusion These results suggest a switch from competition between neighbouring trees under low rainfall conditions towards benefits among neighbours with increasing fire frequencies. Whereas overall woody cover and its patchiness are two independent aspects of savanna woody vegetation patterns, both need to be investigated to obtain a good understanding of the functioning and diversity of savanna ecosystems. [ABSTRACT FROM AUTHOR]

The increased abundance of large carnivores in Europe is a conservation success, but the impact on the behavior and population dynamics of prey species is generally unknown. In Europe, the recolonization of large carnivores often occurs in areas where humans have greatly modified the landscape through forestry or agriculture. Currently, we poorly understand the effects of recolonizing large carnivores on extant prey species in anthropogenic landscapes. Here, we investigated if ungulate prey species showed innate responses to the scent of a regionally exterminated but native large carnivore, and whether the responses were affected by human-induced habitat openness. We experimentally introduced brown bear Ursus arctos scent to artificial feeding sites and used camera traps to document the responses of three sympatric ungulate species. In addition to controls without scent, reindeer scent Rangifer tarandus was used as a noncarnivore, novel control scent. Fallow deer Dama dama strongly avoided areas with bear scent. In the presence of bear scent, all ungulate species generally used open sites more than closed sites, whereas the opposite was observed at sites with reindeer scent or without scent. The opening of forest habitat by human practices, such as forestry and agriculture, creates a larger gradient in habitat openness than available in relatively unaffected closed forest systems, which may create opportunities for prey to alter their habitat selection and reduce predation risk in human-modified systems that do not exist in more natural forest systems. Increased knowledge about antipredator responses in areas subjected to anthropogenic change is important because these responses may affect prey population dynamics, lower trophic levels, and attitudes toward large carnivores. These aspects may be of particular relevance in the light of the increasing wildlife populations across much of Europe. [ABSTRACT FROM AUTHOR]

Wild ungulates are a major consumer of agricultural crops in human dominated landscapes. Across Europe, ungulate populations are leading to intensified human-wildlife conflicts. At the same time, ungulates play a vital role in the structuring and functioning of ecosystems, and are highly appreciated for recreational hunting. Thus, managers often face the challenge of maintaining the benefits of having thriving ungulate populations while simultaneously minimizing their negative impacts. Broadcasting playbacks of predator vocalizations (e.g. dogs barking, wolves howling or humans talking) could potentially be used to induce fear and thereby displace or steer behavior of ungulates from conflict-prone sites resulting in reduced visitation and foraging time and consumption. Predator playback experiments in wilderness areas have repeatedly demonstrated to reduce the preys´ resource use and impacts on the surrounding landscape, but this has not been tested in agricultural fields where human-ungulate conflicts are most pronounced. We responded to this need by conducting a predator playback experiment in multiple crop fields in southern Sweden, where multiple ungulate species (fallow deer, roe deer, red deer, moose, wild boar) coexist, using a novel integrated camera trap – speaker system (ABRs) that broadcasts sounds of choice when a camera is triggered by an ungulate. Predator playbacks (wolf, dog, human) reduced deer patch use and crop damage on wheat fields more than playbacks of control sounds (owl, goose, raven). Our results confirm findings from previous studies in wilderness areas, and demonstrate that broadcasting predator playbacks using ABRs may provide an effective tool to reduce crop damage at the scale and duration of our study. Predator vocalization (human, wolf, dog) broadcasted by integrated camera trap – speaker systems (ABRs) reduced crop damage and patch use by ungulates on vulnerable wheat fields. Ungulates responded most strongly to human vocalizations. [Display omitted] • Predator vocalizations reduced patch use and crop damage by ungulates. • Ungulates responded most strongly to human voices. • Playback systems (ABRs) are a promising tool to reduce negative impact by wildlife. [ABSTRACT FROM AUTHOR]