Abstract: Rare, elusive predators offer few sightings, hindering research with small sample sizes and lack of experimentation. While predators may be elusive, their prey are more readily observed. Prey respond to the presence of a predator, and these fear responses may have population- and community-level consequences. Anti-predator behaviors, such as vigilance, allow us to sidestep the difficulty of direct field studies of large predators by studying them indirectly. Here we used a behavioral indicator, the vigilance behavior of the Himalayan tahr, the snow leopard’s main local prey, to reveal the distribution and habitat use of snow leopards in the Mt. Everest region of Nepal. We combined techniques of conventional field biology with concepts of foraging theory to study prey behavior in order to obtain insights into the predator’s ecology. The Himalayan tahr’s vigilance behavior correlates with the distribution of snow leopard signs. Tahr actually led us to six sightings of snow leopards. We conclude that behavioral indicators provided by prey offer a valuable tool for studying and monitoring stealthy and rare carnivores.

Abstract: Consequences of predation may be particularly
heavy on small populations of herbivores, especially if they
are threatened with extinction. Over the 2006–2010 period, we
documented the effects of the spontaneous return of the endangered
snow leopard on the population of the vulnerable
Himalayan tahr. The study area was an area of central
Himalaya where this cat disappeared c. 40 years before, because
of persecution by man. Snow leopards occurred mainly
in areas close to the core area of tahr distribution. Tahr was the
staple (56.3 %) of snow leopards. After the arrival of this cat,
tahr decreased by more than 2/3 from 2003 to 2010 (mainly
through predation on kids). Subsequently, the density of snow
leopards decreased by 60%from2007 to 2010. The main prey
of snow leopards in Asia (bharal, marmots) were absent in our
study area, forcing snow leopards to specialize on tahr. The
restoration of a complete prey spectrum should be favoured
through reintroductions, to conserve large carnivores and to
reduce exploitation of small populations of herbivores, especially
if threatened.

Abstract: An increasing proportion of the world�s poor is rearing
livestock today, and the global livestock population is growing.
Livestock predation by large carnivores and their retaliatory
killing is becoming an economic and conservation concern.
A common recommendation for carnivore conservation and
for reducing predation on livestock is to increase wild prey
populations based on the assumption that the carnivores
will consume this alternative food. Livestock predation,
however, could either reduce or intensify with increases
in wild prey depending on prey choice and trends in
carnivore abundance. We show that the extent of livestock
predation by the endangered snow leopard Panthera uncia
intensifies with increases in the density of wild ungulate
prey, and subsequently stabilizes. We found that snow leopard
density, estimated at seven sites, was a positive linear
function of the density of wild ungulates�the preferred
prey�and showed no discernible relationship with livestock
density. We also found that modelled livestock predation
increased with livestock density. Our results suggest that
snow leopard conservation would benefit from an increase
in wild ungulates, but that would intensify the problem of
livestock predation for pastoralists. The potential benefits of
increased wild prey abundance in reducing livestock predation
can be overwhelmed by a resultant increase in snow leopard
populations. Snow leopard conservation efforts aimed at
facilitating increases in wild prey must be accompanied by greater assistance for better livestock
protection and offsetting the economic damage caused by carnivores.

Abstract: Human–wildlife conflict arising from livestock-losses to large carnivores is an important challenge faced by conservation. Theory of prey–predator interactions suggests that revival of wild prey populations can reduce predator’s dependence on livestock in multiple-use landscapes. We explore whether 10-years of conservation efforts to revive wild prey could reduce snow leopard’s Panthera uncia consumption of livestock in the coupled human-and-natural Trans-Himalayan ecosystem of northern India. Starting in 2001, concerted conservation efforts at one site (intervention) attempted recovery of wild- prey populations by creating livestock-free reserves, accompanied with other incentives (e.g. insurance, vigilant herding). Another site, 50km away, was monitored as status quo without any interventions. Prey remains in snow leopard scats were examined periodically at five-year intervals between 2002 and 2012 to determine any temporal shift in diet at both sites to evaluate the effectiveness of conservation interventions. Consumption of livestock increased at the status quo site, while it decreased at the intervention-site. At the intervention-site, livestock-consumption reduced during 2002–2007 (by 17%, p = 0.06); this effect was sustained during the next five-year interval, and it was accompanied by a persistent increase in wild prey populations. Here we also noted increased predator populations, likely due to immigration into the study area. Despite the increase in the predator population, there was no increase in livestock-consumption. In contrast, under status quo, dependence on livestock increased during both five-year intervals (by 7%, p=0.08, and by 16%, p=0.01, respectively). These contrasts between the trajectories of the two sites suggest that livestock-loss can potentially be reduced through the revival of wild prey. Further, accommodating counter-factual scenarios may be an important step to infer whether conservation efforts achieve their targets, or not.

Abstract: 1. Spatial responses to risk from multiple predators can precipitate emergent consequences for prey (i.e. multiple-predator effects, MPEs) and mediate indirect interactions between predators. How prey navigate risk from multiple predators may therefore have important ramifications for understanding the propagation of predation-risk effects (PREs) through ecosystems.
2. The interaction of predator and prey traits has emerged as a potentially key driver of antipredator behaviour but remains underexplored in large vertebrate systems, particularly where sympatric prey share multiple predators. We sought to better generalize our understanding of how predators influence their ecosystems by considering how multiple sources of contingency drive prey distribution in a multi-predator–multi-prey system.
3. Specifically, we explored how two sympatric ungulates with different escape tactics—vertically agile, scrambling ibex Capra sibirica and sprinting argali Ovis ammon—responded to predation risk from shared predators with contrasting hunting modes—cursorial wolves Canis lupus and vertical-ambushing, stalking snow leopards Panthera uncia.
4. Contrasting risk posed by the two predators presented prey with clear trade-offs. Ibex selected for greater exposure to chronic long-term risk from snow leopards, and argali for wolves, in a nearly symmetrical manner that was predictable based on the compatibility of their respective traits. Yet, acute short-term risk from the same predator upended these long-term strategies, increasing each ungulates' exposure to risk from the alternate predator in a manner consistent with a scenario in which conflicting antipredator behaviours precipitate risk-enhancing MPEs and mediate predator facilitation. By contrast, reactive responses to wolves led ibex to reduce their exposure to risk from both predators—a risk-reducing MPE. Evidence of a similar reactive risk-reducing effect for argali vis-à-vis snow leopards was lacking.
5. Our results suggest that prey spatial responses and any resulting MPEs and prey-mediated interactions between predators are contingent on the interplay of hunting mode and escape tactics. Further investigation of interactions among various drivers of contingency in PREs will contribute to a more comprehensive understanding and improved forecasting of the ecological effects of predators.