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1. 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. 2. 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. 3. 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.

1. Harvesting of large mammals is usually not random, and directional selection has been identified as the main cause of rapid evolution. However, selective harvesting in meat and recreational hunting cultures does not automatically imply directional selection for trait size. 2. Harvesting selectivity is more than a matter of hunter preference. Selection is influenced by management regulations, hunting methods, animal trait variance, behaviour and abundance. Most studies of hunter selection only report age- or sex-specific selection, or differences in trait size selection among hunting methods or groups of hunters, rather than trait size relative to the age-specific means required for directional selection. 3. Synthesis and applications. Managers aiming to avoid rapid evolution should not only consider directional selection and trophy hunting but also mitigate other important evolutionary forces such as harvesting intensity per se, and sexual selection processes that are affected by skewed sex ratios and age structures.

Cooperative hunting is believed to have important implications for the evolution of sociality and advanced cognitive abilities. Variation in the level of hunt organisation amongst species and how their cognitive, behavioural and athletic adaptations may contribute to observed patterns of cooperative hunting behaviour, however, are poorly understood. We, therefore, reviewed the literature for evidence of different levels of hunt organisation and cooperation in carnivorans and examined their social and physical adaptations for hunting. Descriptions of group hunting were scarce for many species and often of insufficient detail for us to be able to classify the level of hunt organisation involved. However, despite this, reports of behaviour fitting the description of collaboration, the most advanced level of hunt organisation, were found in over half the carnivorans reported to hunt cooperatively. There was no evidence that this behaviour would require advanced cognitive abilities. However, there was some evidence that both social mechanisms reducing aggression between group members and information transfer amongst individuals may aid cooperative hunting. In general, the cooperative strategies used seemed to depend partly on the species' locomotor abilities and habitat. There was some evidence that individuals take on consistent roles during cooperative hunts in some species, but it was not clear if this reflects individuals' physical differences, social factors or life experiences. Better understanding of the social, cognitive and physical mechanisms underlying cooperative hunting, and indeed establishing to what degree it exists in the first instance, will require more data for multiple individuals and species over many hunts.

Tanzania holds most of the remaining large populations of African lions (Panthera leo) and has extensive areas of leopard habitat (Panthera pardus), and both species are subjected to sizable harvests by sport hunters. As a first step toward establishing sustainable management strategies, we analyzed harvest trends for lions and leopards across Tanzania's 300,000 km 2 of hunting blocks. We summarize lion population trends in protected areas where lion abundance has been directly measured and data on the frequency of lion attacks on humans in high-conflict agricultural areas. We place these findings in context of the rapidly growing human population in rural Tanzania and the concomitant effects of habitat loss, human-wildlife conflict, and cultural practices. Lion harvests declined by 50% across Tanzania between 1996 and 2008, and hunting areas with the highest initial harvests suffered the steepest declines. Although each part of the country is subject to some form of anthropogenic impact from local people, the intensity of trophy hunting was the only significant factor in a statistical analysis of lion harvest trends. Although leopard harvests were more stable, regions outside the Selous Game Reserve with the highest initial leopard harvests again showed the steepest declines. Our quantitative analyses suggest that annual hunting quotas be limited to 0.5 lions and 1.0 leopard/1000 km 2 of hunting area, except hunting blocks in the Selous Game Reserve, where harvests should be limited to 1.0 lion and 3.0 leopards/1000 km 2 . Tanzania mantiene la mayoría de las poblaciones remanentes de leones Africanos (Panthera leo) y tiene extensas áreas de hábitat de leopardo (Panthera pardus), y ambas especies son sujetas a cosechas considerables por cazadores deportivos. Como un primer paso hacia el establecimiento de estrategias de manejo sustentable, analizamos las tendencias de cosecha de leones y leopardos en los 300,000 km 2 de bloques de cacería de Tanzania. Sintetizamos las tendencias poblacionales de leones en áreas protegidas donde la abundancia de leones ha sido medida directamente, así como datos sobre la frecuencia de ataques de leones sobre humanos en áreas agrícolas altamente conflictivas. Ubicamos estos resultados en el contexto de la población humana en rápido crecimiento en Tanzania rural y los efectos concomitantes de la pérdida de hábitat, el conflicto humanos-vida silvestre y las prácticas culturales. Las cosechas de leones han declinado 50% en Tanzania entre 1996 y 2008, y las áreas de cacería con las cosechas iniciales más altas sufrieron las declinaciones más pronunciadas. Aunque cada parte del país está sujeto a alguna forma de impacto antropogénico por habitantes locales, la intensidad de la cacería deportiva fue el único factor significativo en el análisis estadístico de las tendencias poblacionales de leones. Aunque las cosechas de leopardos fueron más estables, regiones fuera de la Reserva de Caza Selous con las cosechas iniciales de leopardos más altas también mostraron las declinaciones más pronunciadas. Nuestros análisis cuantitativos sugieren que las cuotas anuales de cacería se limiten a 0.5 leones y 1.0 leopardo/1000 km 2 de área de cacería, excepto los bloques de cacería en la Reserva de Caza Selous, donde las cosechas deben limitarse a 1.0 león y 3.0 leopardos/1000 km 2 .

Cooperation often involves behaviours that reduce immediate payoffs for actors. Delayed benefits have often been argued to pose problems for the evolution of cooperation because learning such contingencies may be difficult as partners may cheat in return. Therefore, the ability to achieve stable cooperation has often been linked to a species' cognitive abilities, which is in turn linked to the evolution of increasingly complex central nervous systems. However, in their famous 1981 paper, Axelrod and Hamilton stated that in principle even bacteria could play a tit-for-tat strategy in an iterated Prisoner's Dilemma. While to our knowledge this has not been documented, interspecific mutualisms are present in bacteria, plants and fungi. Moreover, many species which have evolved large brains in complex social environments lack convincing evidence in favour of reciprocity. What conditions must be fulfilled so that organisms with little to no brainpower, including plants and single-celled organisms, can, on average, gain benefits from interactions with partner species? On the other hand, what conditions favour the evolution of large brains and flexible behaviour, which includes the use of misinformation and so on? These questions are critical, as they begin to address why cognitive complexity would emerge when ‘simple’ cooperation is clearly sufficient in some cases. This paper spans the literature from bacteria to humans in our search for the key variables that link cooperation and deception to cognition.

We present evidence of a novel form of group hunting. Individual sailfish (Istiophorus platypterus) alternate attacks with other group members on their schooling prey (Sardinella aurita). While only 24% of attacks result in prey capture, multiple prey are injured in 95% of attacks, resulting in an increase of injured fish in the school with the number of attacks. How quickly prey are captured is positively correlated with the level of injury of the school, suggesting that hunters can benefit from other conspecifics' attacks on the prey. To explore this, we built a mathematical model capturing the dynamics of the hunt. We show that group hunting provides major efficiency gains ( prey caught per unit time) for individuals in groups of up to 70 members. We also demonstrate that a free riding strategy, where some individuals wait until the prey are sufficiently injured before attacking, is only beneficial if the cost of attacking is high, and only then when waiting times are short. Our findings provide evidence that cooperative benefits can be realized through the facilitative effects of individuals' hunting actions without spatial coordination of attacks. Such 'proto-cooperation' may be the pre-cursor to more complex group-hunting strategies.

Predicting and mitigating the effects of invasive Indo-Pacific lionfishPterois volitanson Caribbean fish communities requires a thorough understanding of the species’ predation behaviour in the invaded range, including the types and amounts of prey consumed and how foraging patterns vary in relation to extrinsic conditions. We studied the activity levels and prey consumption rates of lionfish on 12 shallow coral reefs in the Bahamas in relation to time of day and prey availability. Lionfish predation rates and activity levels were significantly higher during crepuscular (dawn and dusk) periods than at mid-day. Available prey fish biomass was highest at dawn but lower at mid-day and dusk, suggesting that lionfish predation activity is not limited by prey availability alone. Our calculated average daily mass-specific prey consumption rates, which incorporated daily variation, was ~3 times the estimates obtained from studies of captive lionfish in their native range and of invasive lionfish observed only during the day. Our results will help to predict more accurately the effect of predation by invasive lionfish on native reef fish communities.

Anthropological theory suggests direct links between the origins of cooperation in hominins and a shift toward an energy-rich diet. Although the degree to which early hominins ate meat remains controversial, here we reevaluate the notion, originally suggested by Schaller and Lowther in 1969, that mammalian carnivores can shed light on human origins. Precisely when cooperation evolved in hominins or carnivores is unknown, but species from both groups cooperatively hunt large game, defend resources, guard against predators, and rear young. We present a large-scale comparative analysis of extant carnivore species, quantifying anatomical, ecological, and behavioral correlates of cooperation to determine whether metabolic rate, body and relative brain size, life history traits, and social cohesion coevolved with cooperation. We focus heavily on spotted hyenas, which live in more complex societies than other carnivores. Hyenas regularly join forces with kin and nonkin to hunt large antelope and to defend resources during intergroup conflicts and disputes with lions. Our synthesis highlights reduced sexual dimorphism, increased reproductive investment, high population density, fission-fusion dynamics, endurance hunting of big game in open habitats, and large brains as important correlates of cooperation among carnivores. We discuss the relevance of our findings to understanding the origins of cooperation in hominins.

Indo-Pacific lionfish, mainlyPterois volitans, are currently invading coral reefs throughout the Caribbean region, where they have the potential to outcompete and prey upon a wide range of native reef animals. Here, we derive the first estimates of rates of predation by lionfish from field observations on natural reefs around New Providence, Bahamas. Although lionfish are reported to be crepuscular in their native range, they were very active during daylight hours. Lionfish were observed hunting at least 19 reef fish species, in at least 9 families. They hunted significantly more on overcast days and at greater depths, and frequently hunted near aggregations of fish at cleaning stations. Lionfish consumed native fish at an average rate of 1.44 kills h–1(0.29 kills h–1on clear days and 2.29 kills h–1on overcast days). This estimate may be conservative if lionfish hunt also between dusk and dawn. This rate is considerably higher than the only known prey consumption rate forP. volitans, which is extrapolated from ad libitum feeding of fish from the native range. Our results imply that using published predation rates from the native range to predict the impacts of lionfish on native Caribbean fish could lead to severe underestimation of these impacts.

Risk to predators hunting dangerous prey is an emerging area of research and could account for possible persistent differences in gray wolf (Canis lupus) pack sizes. We documented significant differences in long-term wolf-pack-size averages and variation in the Superior National Forest (SNF), Denali National Park and Preserve, Yellowstone National Park, and Yukon, Canada (p<0.01). The SNF differences could be related to the wolves' risk when hunting primary prey, for those packs (N=3) hunting moose (Alces americanus) were significantly larger than those (N=10) hunting white-tailed deer (Odocoileus virginianus) (F1,8=16.50, p=0.004). Our data support the hypothesis that differential pack-size persistence may be perpetuated by differences in primary prey riskiness to wolves, and we highlight two important extensions of this idea: (1) the potential for wolves to provision and defend injured packmates from other wolves and (2) the importance of less-risky, buffer prey to pack-size persistence and year-to-year variation.