Carnivore Predation Research Articles

Are the livestock guarding dogs where they are supposed to be?

In many parts of the world, livestock guarding dogs (LGDs) are considered one of the most powerful prevention tools against carnivore predation on domestic animals, but how they behave when left unsupervised with their flock on pastures is mostly unknown. We monitored 29 LGDs with GPS (Global Positioning System) collars in order to investigate their space use and association with livestock. UDOI (Utilization Distribution Overlap Index) and the VI (Volume of Intersection) Index for 50% and 95% kernel isopleths were calculated to quantify the overlap and the similarity in the use of space for the core area and for the whole movement range of sheep and dogs. Linear mixed models were implemented to evaluate how dog-sheep distance was influenced by environmental (land use, percentage of trees and shrubs in the pasture, size of pasture), dog-related (sex, age), and farming-related variables (number of livestock guarding dogs associated with the flock, herd size). Finally, we tested the usefulness of GPS pet collars in managing LGDs. LGDs spent the majority of their time close to livestock, sharing the same areas but using the space in a different way. Dog-sheep distance was mostly influenced by the environmental variable land use, and the age of the dog. In fact, dogs and sheep tended to separate more in pastures with a high percentage of trees and shrubs, and less in pastures close to inhabited areas. Moreover, older dogs were more associated to the flock compared to younger individuals. GPS pet collars can be an important tool in managing LGDs, as farmers are able to check the position of their dogs and their flock at any time. This can allow producers to improve their management of LGDs, and to limit conflicts with neighbors and accidents. In this study, we demonstrated that the monitored LGDs did not leave the flock unattended when left unsupervised, although further insights into how they behave would support a full evaluation.

Herders’ ecological knowledge and carnivore predation on livestock investigations in Makgadikgadi and Nxai national parks, Botswana

Botswana is one of the countries in Southern Africa that pay compensation for human properties damaged by wildlife. Before compensation is paid, a thorough investigation on determining wildlife species that have caused the damage is mandatory. Because of insufficient resources by the Department of Wildlife and National Parks, the initial investigation is carried out by herders. Three basic indicators are used to determine carnivore predation; sighting the carnivore at the kill, tracks of the predator and examining the carcasses. In this study, we tested herders’ knowledge on the above three indicators. The study was conducted in a communal area around Makgadikgadi and Nxai national parks, Botswana, where the main activities practiced by the local communities is pastoral farming. In general, there was a significant association between reported and perceived incidents of predation for all carnivores at all distances from protected areas. Herders were able to identify the large carnivores visually. But they had difficulties in identifying carnivore tracks and kill characteristics. The results demonstrate the importance of involvement of local communities in human–wildlife conflict management. However, more education regarding identification of carnivore tracks and kill behaviour is needed for herders in the study area.Conservation implications: Based on the results of this study, this calls for a change in the management of human–wildlife conflict (HWC) and administration of the compensation scheme. Decentralising HWC to local communities using existing government structures that exist at local level will not only supplement the inadequate resources by the Department of Wildlife and National Parks (DWNP) to effectively mitigate the problem, but also empower local communities’ participation in wildlife management.

Hunting exacerbates the response to human disturbance in large herbivores while migrating through a road network

AbstractMigrations of large ungulates are globally threatened in environments affected by increasing human disturbance, rising large carnivore predation, deteriorating habitat quality, and changing climate. Animals migrating outside of protected areas can be exposed to greater human pressure, and this effect can be stronger when humans are perceived to be a predation risk, such as during hunting seasons. Using four consecutive years of satellite telemetry data (n = 138 migration events), we compared habitat selection, movement, and behavior of a large partially migratory herbivore while migrating through a heterogeneous landscape in spring and fall. We tested the hypothesis that fall hunting exacerbates the response of a large herbivore exposed to human disturbance while migrating through a road network. All elk (Cervus elaphus) selected greater forest cover, reduced movement rates, and avoided roads during fall‐day than in any other season or time of day. Avoidance of roads was reduced during spring at night, for example, the time period of no hunting with fewest people on roads. Elk using stopovers in fall displayed different seasonal and diurnal behaviors between sexes in response to the disturbance. Females used steeper terrain during fall‐day and males did not use this strategy in fall. Male avoidance of roads was much stronger than females during fall‐day and males were less likely to cross a road during fall. Such responses are probably linked to higher hunting pressure on males vs. females. Finally, we found that elk spent more time feeding during spring migration compared to the fall migration and elk vigilance was >3 times higher in the fall hunting season. Our results provide insights into the effect of fear of humans on the ecology of both sexes of a migrating large herbivore when using stopovers. Such changes in behavior and stopover use might affect animal fitness by decreasing foraging, cause displacement from high‐quality habitats, or affect the permeability of migration route stopovers.

Bluebirds perceive prey switching by Cooper’s hawks across an urban gradient and adjust reproductive effort

ABSTRACTUrban-adapting carnivorous predators such as the Cooper’s hawk appear to be adjusting their diet in urban areas to mostly include larger-bodied adult birds rather than nest contents, compared to Cooper’s hawks in natural areas. If adult prey in urban areas are relatively more threatened by predation relative to their offspring and non-urban adults, then life-history theory predicts contrasting shifts in urban vs. non-urban reproductive behavior and effort. We tested whether urban and non-urban Eastern bluebirds exhibited contrasting reproductive effort consistent with shifts in the relative risk perception of adult vs. nest predation. At urban sites, Eastern bluebirds using nest boxes exposed to broadcasts of Cooper’s hawk vocalizations exhibited enhanced reproductive parameters compared to controls, whereas the opposite trend occurred in box-nesting bluebirds at non-urban sites. As predicted by theory, given prey life-stage switching by a dominant predator, increased perception of predation risk from hawks led to opposing reproductive strategies in urban vs. non-urban habitats. Results align with increasing evidence that urban predation pressures, prey risk perception, and reproductive investment patterns are distinct from those of natural habitats.

Chemical mediation as a structuring element in marine gastropod predator-prey interactions

Covering: up to 2017Chemical mediation regulates behavioral interactions between species and thus affects population structure, community organization and ecosystem function. Among marine taxa that have developed chemical mediation strategies, gastropods belong to a diverse group of molluscs found worldwide, including species with a coiled, reduced or absent shell. Most gastropods use natural products to mediate a wide range of behaviors such as defense, prey location or interactions with con- and hetero-geners. Their chemically defended diet, such as cyanobacteria, algae, sponges, bryozoans and tunicates, provides them with a considerable opportunity either as shelter from predators, or as a means to enhance their own chemical defense. In addition to improving their defenses, molluscs also use prey secondary metabolites in complex chemical communication including settlement induction, prey detection and feeding preferences. The assimilation of prey secondary metabolites further provides the opportunity for interactions with conspecifics via diet-derived chemical cues or signals. This review intends to provide an overview on the sequestration, detoxification, and biotransformation of diet-derived natural products, as well as the role of these compounds as chemical mediators in gastropod-prey interactions.

六斑月瓢虫取食不同猎物的生长发育及繁殖特性

PDF HTML阅读 XML下载 导出引用 引用提醒 六斑月瓢虫取食不同猎物的生长发育及繁殖特性 DOI: 10.5846/stxb201606111117 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 中央级公益性科研院所基本科研业务费专项（2015hzs1J003）；国家基础研究计划（973计划2013CB127600） Influence of three prey species on the development and fecundity of Menochilus sexmaculata Fabricius Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:六斑月瓢虫是我国农、林、蔬、果生态系统中重要的捕食性天敌之一，能够捕食多种猎物。不同的猎物质量显著影响捕食性天敌昆虫的活力。为评价取食不同猎物对六斑月瓢虫生物学特性的影响，采用实验种群生命表的方法研究了六斑月瓢虫取食烟粉虱、豆蚜和玉米蚜的生长发育和繁殖情况。结果表明，六斑月瓢虫取食烟粉虱的世代发育历期最长、存活率、雌虫寿命和繁殖力最低，分别为（26.15±0.42）d、（52.95±1.98）%、（53.73±2.17）d和（157.67±16.79）粒/雌；而取食玉米蚜的世代发育历期最短、存活率、雌虫寿命和繁殖力最高，分别为（16.40±0.49）d、（77.93±0.76）%、（68.33±4.31）d和（798.77±44.29）粒/雌；取食豆蚜时的各生物学参数介于两者之间。种群生命表参数也反映了类似的结果，取食烟粉虱的净增殖率（R0）、内禀增长率（rm）和周限增长率（λ）最低分别为71.216、0.092和1.094，世代平均历期（T）最长为47.377d；取食玉米蚜的R0、rm和λ最高分别为290.281、0.131和1.143，T最短为42.428d。总体来看，相对于烟粉虱而言，蚜虫更适合六斑月瓢虫的生长发育和繁殖，且玉米蚜优于豆蚜。 Abstract:The ladybeetle Menochilus sexmaculata Fabricius (Coleoptea:Coccinellidae) is a common and abundant indigenous natural enemy of Hemipteran pests, such as aphids, whiteflies and scale insects, which are all serious pests of various field crops and greenhouse vegetables and thus cause considerable damage in China. Food quality is one of the most important factors that can influence the vigor of carnivorous predators because not all prey species are equally suitable. In order to evaluate the biological characteristics of M. sexmaculata preying on differential prey species, in the present study, the influence of three prey species-Bemisia tabaci (Gennadius), Aphis craccivora Koch, and Rhopalosiphum maidis (Fitch)-on the development and fecundity of M. sexmaculata was studied, using the life-table method, under laboratory conditions. The results showed that the development, survival rate, longevity, reproduction, and life-table parameters of M. sexmaculata differed significantly with different prey species. The shortest developmental period for M. sexmaculata (generational period) was observed when they preyed on R. maidis, with a mean value of (16.40±0.49) days, whereas the longest developmental period ((26.15±0.42) days) was observed when the preyed on B. tabaci. The highest survival rate ((77.93±0.76)%) was observed when the prey species was R. maidis and the lowest survival rate ((52.95±1.98)%) was observed when the prey species was B. tabaci. The highest fecundity ((798.77±44.29) eggs/female) and longest longevity ((68.33±4.31) d) were observed when R. maidis was used as prey. Take these life-table parameters together, we determined that the highest values of net reproductive rate (R0), intrinsic rate of increase (rm), and finite rate of increase (λ) were observed when the prey species was R. maidis-these values were 290.281, 0.131, and 1.143, respectively. Moreover, the results also indicated that the generation time was lowest (T=42.428 d) when the prey species was R. maidis. In contrast, the values of the life-table parameters R0, rm, and λ were lowest when M. sexmaculata preyed on B. tabaci (71.216, 0.092, and 1.094, respectively). The T value (47.377 d) was highest when the prey species was B. tabaci. Experimental data for A. craccivora were intermediate between those for the other two prey species. On the basis of these findings, the order of suitability of the three prey organisms for M. sexmaculata is R. maidis > A. craccivora > B. tabaci. The results indicated that the aphid is a more suitable prey for the ladybeetle than the whitefly, and that R. maidis is the most suitable prey for M. sexmaculata of the three prey species tested and can serve as a rearing diet for mass production of M. sexmaculata under laboratory conditions. 参考文献 相似文献 引证文献

Predator control should not be a shot in the dark

Livestock owners traditionally use various non‐lethal and lethal methods to protect their domestic animals from wild predators. However, many of these methods are implemented without first considering experimental evidence of their effectiveness in mitigating predation‐related threats or avoiding ecological degradation. To inform future policy and research on predators, we systematically evaluated evidence for interventions against carnivore (canid, felid, and ursid) predation on livestock in North American and European farms. We also reviewed a selection of tests from other continents to help assess the global generality of our findings. Twelve published tests – representing five non‐lethal methods and 7 lethal methods – met the accepted standard of scientific inference (random assignment or quasi‐experimental case‐control) without bias in sampling, treatment, measurement, or reporting. Of those twelve, prevention of livestock predation was demonstrated in six tests (four non‐lethal and two lethal), whereas counterintuitive increases in predation were shown in two tests (zero non‐lethal and two lethal); the remaining four (one non‐lethal and three lethal) showed no effect on predation. Only two non‐lethal methods (one associated with livestock‐guarding dogs and the other with a visual deterrent termed “fladry”) assigned treatments randomly, provided reliable inference, and demonstrated preventive effects. We recommend that policy makers suspend predator control efforts that lack evidence for functional effectiveness and that scientists focus on stringent standards of evidence in tests of predator control.

Lizards of the family Hodzhakuliidae (Scincomorpha) from the lower Cretaceous of Mongolia

The lizard family Hodzhakuliidae (Scincomorpha) endemic to the Early Cretaceous of Central Asia is characterized in the light of finds from the Khoobur (Hoovor) locality in Mongolia. Available material includes Hodzhakulia magna Nessov, 1985 described from the Upper Albian of Uzbekistan and three new genera and species. It is proposed that Hodzhakuliidae occupied the adaptive zone of small carnivorous predators before the appearance of Platynota.

Carnivores’ diversity and conflicts with humans in Musk Deer National Park, Azad Jammu and Kashmir, Pakistan

Pakistan’s northern expanses have rich diversity of mammalian carnivores, but majority of them are either threatened or endangered due to habitat degradation and conflict with humans. This study was conducted between May and June 2014 with the aim of determining the diversity of mammalian carnivores and their conflict with humans in Musk Deer National Park (MDNP), Azad Jammu and Kashmir (AJK). Forty motion-triggered cameras (Reconyx™) were installed in different watersheds of MDNP to determine carnivore species diversity. A human-carnivore conflict study was conducted through semi-structured questionnaires where 149 respondents were randomly selected from 18 villages in the park. A total of nine carnivore species were documented, namely snow leopard (Panthera uncia), common leopard (Panthera pardus), leopard cat (Prionailurus bengalensis), brown bear (Ursus arctos), Asiatic black bear (Ursus thibetinus), grey wolf (Canis lupus), red fox (Vulpes vulpes), stone marten (Martes foina), and yellow-throated marten (Martes flavigula). During the past year, a total of 817 livestock were lost to disease and carnivore predation. Carnivores were held responsible for 276 livestock losses which translated into an annual economic loss of USD 28,145 (USD 189 per household). Both Asiatic black bear and brown bear also damaged maize and potato crops causing economic losses of USD 16,330 (USD 110 per household). Depredation of livestock was greatly affected by four factors: prey type, season of depredation, location of depredation, and livestock guarding practices. Based on the responses, the people of Folwai village showed the most negative perception towards carnivores. Majority of the respondents declared grey wolf, brown bear, and Asiatic black bear to be the most dangerous carnivores in the park. Our results showed that MDNP has rich diversity of carnivores but their survival in the park is in danger due to conflict with humans over excessive livestock depredations and crop raiding. Active livestock guarding practices can reduce carnivore attacks. Educating local people, vaccinating their livestock, and compensating affected families can greatly reduce negative perceptions.

Coupling bio-logging with nutritional geometry to reveal novel insights into the foraging behaviour of a plunge-diving marine predator

ABSTRACTIt is widely believed that predators maximise their energy intake while foraging and consume prey that are nutritionally similar. We combined GPS data loggers, miniaturised cameras, dietary sampling and nutritional geometry to examine the nutritional variability in the prey and selected diet, and foraging performance, of the masked booby (Sula dactylatra tasmani), a wild carnivore and marine top predator. Data loggers also revealed no significant differences between sexes in the foraging performance of chick-rearing adults. Females provided more food to their chicks than the males and, regardless of the nutritional variability of prey consumed, both sexes showed similar amounts of protein and lipid in their diets. Miniaturised cameras combined with nutritional analysis of prey provided, for the first time, fine-scale detail of the amounts of macronutrients consumed in each plunge dive and the overall foraging trip. Our methodology could be considered for future studies that aim to contribute to the general understanding of the behavioural and physiological mechanisms and ecological and evolutionary significance of animal foraging (e.g. energy expenditure budgets and prey selection for self- and offspring-feeding that could lead to sex-specific foraging strategies).

Understanding public perceptions of risk regarding outdoor pet cats to inform conservation action.

Free-ranging domestic cats (Felis catus) incur and impose risks on ecosystems and represent a complex issue of critical importance to biodiversity conservation and cat and human health globally. Prior social science research on this topic is limited and has emphasized feral cats even though owned cats often comprise a large proportion of the outdoor cat population, particularly in urban areas. To address this gap, we examined public risk perceptions and attitudes toward outdoor pet cats across varying levels of urbanization, including along the wildland-urban interface, in Colorado (U.S.A.), through a mail survey of 1397 residents. Residents did not view all types of risks uniformly. They viewed risks of cat predation on wildlife and carnivore predation on cats as more likely than disease-related risks. Additionally, risk perceptions were related to attitudes, prior experiences with cats and cat-wildlife interactions, and cat-owner behavior. Our findings suggest that changes in risk perceptions may result in behavior change. Therefore, knowledge of cat-related risk perceptions and attitudes could be used to develop communication programs aimed at promoting risk-aversive behaviors among cat owners and cat-management strategies that are acceptable to the public and that directly advance the conservation of native species.

Non‐lethal management of carnivore predation: long‐term tests with a startle reflex‐based deterrence system on a fish farm

AbstractCarnivore depredation on human livestock is a worldwide problem with few viable solutions. Non‐lethal management tools such as acoustic devices show highly varying success and often pose a conservation risk due to noise pollution and habitat degradation. We tested the long‐term effectiveness of a deterrence system which harnesses an autonomous reflex (startle) to selectively inflict avoidance responses in a target species (phocid seals) by emitting band‐limited noise pulses with sharp onset times. Seal predation was monitored at a marine salmon farm (test site) over a full production cycle (19 month) with a multi‐transducer deterrent system deployed for the final year. Predation was also monitored for several months at two control sites and additional short‐term tests were carried out at sites which suffered higher predation rates. Generalized linear (mixed) models revealed that sound exposure caused a 91% reduction in lost fish when comparing predation levels within the test site and 97% when comparing the test site against both control sites. Similarly, sound exposure led to a 93% reduction in the number of fish lost due to seal damage at a short‐term test site. Visual monitoring of marine mammals around the long‐term test site showed that the number of seal surfacings within 100 m from the loudspeakers was only slightly lower during sound exposure. Harbour porpoise and otter distribution around the farm was not affected by sound exposure. By adjusting the frequency composition of startle stimuli, our method has the potential to provide solutions for managing human–wildlife conflicts in terrestrial and marine habitats by selectively deterring target species.

Eagles, owls, and coyotes (oh my!): Taphonomic analysis of rabbits and guinea pigs fed to captive raptors and coyotes

There is the potential for multiple accumulating agents of small mammals (<4.5kg body weight) at fossil sites, however, the lack of diverse predator and prey experimental and actualistic studies often makes it difficult to attribute the accumulator(s) of small mammals. I report the results of experimentally created assemblages of rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus) fed to a bald eagle (Haliaeetus leucocephalus), great horned owl (Bubo virginianus), and coyote (Canis latrans). The analysis provides a taphonomic assessment of two small mammal taxa that differ in size and build and are broadly representative of small mammals recovered from archaeological sites. The ingested and non-ingested portions of the prey remains were analyzed for skeletal-, digested-, deleted-, and fractured-part representation, bone breakage, and bone surface modifications. The rabbit and guinea pig samples are compared and taphonomic differences between predators and prey taxa are observed. The predators produced variable and distinctive intra- and interspecific skeletal-, digested-, deleted-, and fractured part profiles. Bone surface modification frequency differences between the samples show a mixture of significant and non-significant intra- and interspecific comparisons. This study expands the range of small mammal experimental and actualistic studies to include prey of underrepresented size and build (guinea pigs) and characterizes the signatures of predator accumulations of small mammals. Often archaeological assemblages feature a mixture of accumulators, this analysis of raptor and mammalian carnivore predation on rabbits and guinea pigs will aid in the differentiation of predation between raptors, mammalian carnivores, and humans in the archaeological record.

갈색띠매물고둥, Neptunea cumingii Crosse에 의한 북방전복, Haliotis discus hannai (Ino) 치패의 피식

어린 북방전복 (Haliotis discus hannai) 에 대한 포식자 (불가사리류 제외) 의 존재 여부를 확인하고자 경북 울진 연안 3개 해역 (양정, 죽진 및 봉평)에서 SCUBA diving을 이용하여 2014년 2월부터 12월까지 총 9회에 걸친 직접 관찰 조사를 수행하였다. 조사 결과 수심 10 m 이내 (최대 15 m)의 해역에서 상대적 암반 구성 비율이 가장 높은 죽진 해역 (60.3%)에서 어린 북방전복을 포식하고 있는 총 6개체의 갈색띠매물고둥 (Neptunea cumingii)이 발견되었다. 따라서, 본 연구결과는 갈색띠매물고둥이 어린 북방전복에 대한 포식자라는 새로운 사실을 제시하고 있다. The presence of predators (excluding starfishes) of disk abalone, Haliotis discus hannai was directly investigated by nine SCUBA divings during February-December 2014 at the coastal areas of Yangjeong, Jukjin and Bongpyeong, Uljin, Korea, where the young disk abalone seedlings were artificially released. The results revealed that a total of six individuals of Neptunea cumingii that were feeding on the young disk abalone were observed within the water depth 10m at the coastal area of Jukjin, of which bottom substrate consists of the relatively high composition rate of rocks (60.3%). Though N. cumingii is well known as a carnivorous predator of diverse marine invertebrates such as live mussels (Mytilus spp.) it is the first report that this predator also feeds on the disk abalones. Thus, our results strongly suggest that the future artificial release projects around Korean coasts necessitate extermination works of predators including newly observed N. cumingii in this study as well as previously known starfishes prior to the releases of young Pacific abalone seedlings.

A cross‐system meta‐analysis reveals coupled predation effects on prey biomass and diversity

Predator diversity and abundance are under strong human pressure in all types of ecosystems. Whereas predator potentially control standing biomass and species interactions in food webs, their effects on prey biomass and especially prey biodiversity have not yet been systematically quantified. Here, we test the effects of predation in a cross‐system meta‐analysis of prey diversity and biomass responses to local manipulation of predator presence. We found 291 predator removal experiments from 87 studies assessing both diversity and biomass responses. Across ecosystem types, predator presence significantly decreased both biomass and diversity of prey across ecosystems. Predation effects were highly similar between ecosystem types, whereas previous studies had shown that herbivory or decomposition effects differed fundamentally between terrestrial and aquatic systems based on different stoichiometry of plant material. Such stoichiometric differences between systems are unlikely for carnivorous predators, where effect sizes on species richness strongly correlated to effect sizes on biomass. However, the negative predation effect on prey biomass was ameliorated significantly with increasing prey richness and increasing species richness of the manipulated predator assemblage. Moreover, with increasing richness of the predator assemblage present, the overall negative effects of predation on prey richness switched to positive effects. Our meta‐analysis revealed strong general relationships between predator diversity, prey diversity and the interaction strength between trophic levels in terms of biomass. This study indicates that anthropogenic changes in predator abundance and diversity will potentially have strong effects on trophic interactions across ecosystems.SynthesisThe past centuries we have experienced a dramatic loss of top–predator abundance and diversity in most types of ecosystems. To understand the direct consequences of predator loss on a global scale, we quantitatively summarized experiments testing predation effects on prey communities in a cross‐system meta‐analysis. Across ecosystem types, predator presence significantly decreased both biomass and diversity of prey, and predation effects were highly similar. However, with increasing predator richness, the overall negative effects of predation on prey richness switched to positive ones. Anthropogenic changes in predator communities will potentially have strong effects on prey diversity, biomass, and trophic interactions across ecosystems.

Predation of bat (Molossus molossus: Molossidae) by the centipede Scolopendra viridicornis (Scolopendridae) in Southern Amazonia

Centipedes are opportunistic carnivore predators, and large species can feed on a wide variety of vertebrates, including bats. The aim of this study was to report the third record of bat predation by centipedes worldwide, the first record in the Amazon region, while covering aspects of foraging, capture and handling of prey. We observed the occurence in a fortuitous encounter at Cristalino State Park, located in the Amazon region of the state of Mato Grosso, Brazil. The attack took place in a small wooden structure, at about three meters from the floor, and was observed for 20 minutes. During the observation, the centipede stung the neck and abdominal region of the bat several times, grabbing the prey with its 15 pairs of front legs while hanging from the ceiling with its hind legs. This type of observation suggests that vertebrates can be important preys for invertebrates such as giant centipedes, both for its nutritional composition and for the amount of energy available in a single prey.

Solitary Ethiopian wolves increase predation success on rodents when among grazing gelada monkey herds

Mixed-species associations generally form to increase foraging success or to aid in the detection and deterrence of predators. While mixed-species associations are common among mammals, those involving carnivorous predators and potential prey species are seldom reported. On the Guassa Plateau, in the Ethiopian highlands, we observed solitary Ethiopian wolves (Canis simensis) foraging for rodents among grazing gelada monkey (Theropithecus gelada) herds. The tolerant and sometimes prolonged (> 1h) associations contrasted with the defensive behaviors exhibited by geladas toward other potential predators. Ethiopian wolves spent a higher proportion of time foraging and preyed more successfully on rodents when among geladas than when alone, providing evidence that gelada herds increase the vulnerability of subterranean rodents to predation. Ethiopian wolves appear to habituate gelada herds to their presence through nonthreatening behavior, thereby foregoing opportunistic foraging opportunities upon vulnerable juvenile geladas in order to feed more effectively on rodents. For Ethiopian wolves, establishing proximity to geladas as foraging commensals could be an adaptive strategy to elevate foraging success. The novel dynamics documented here shed light on the ecological circumstances that contribute to the stability of mixed groups of predators and potential prey.

Monitoring rarity: the critically endangered Saharan cheetah as a flagship species for a threatened ecosystem.

Deserts are particularly vulnerable to human impacts and have already suffered a substantial loss of biodiversity. In harsh and variable desert environments, large herbivores typically occur at low densities, and their large carnivore predators occur at even lower densities. The continued survival of large carnivores is key to healthy functioning desert ecosystems, and the ability to gather reliable information on these rare low density species, including presence, abundance and density, is critical to their monitoring and management. Here we test camera trap methodologies as a monitoring tool for an extremely rare wide-ranging large felid, the critically endangered Saharan cheetah (Acinonyx jubatus hecki). Two camera trapping surveys were carried out over 2–3 months across a 2,551km2 grid in the Ti-n-hağğen region in the Ahaggar Cultural Park, south central Algeria. A total of 32 records of Saharan cheetah were obtained. We show the behaviour and ecology of the Saharan cheetah is severely constrained by the harsh desert environment, leading them to be more nocturnal, be more wide-ranging, and occur at lower densities relative to cheetah in savannah environments. Density estimates ranged from 0.21–0.55/1,000km2, some of the lowest large carnivore densities ever recorded in Africa, and average home range size over 2–3 months was estimated at 1,583km2. We use our results to predict that, in order to detect presence of cheetah with p>0.95 a survey effort of at least 1,000 camera trap days is required. Our study identifies the Ahaggar Cultural Park as a key area for the conservation of the Saharan cheetah. The Saharan cheetah meets the requirements for a charismatic flagship species that can be used to “market” the Saharan landscape at a sufficiently large scale to help reverse the historical neglect of threatened Saharan ecosystems.

Assessing the relative importance of landscape and husbandry factors in determining large carnivore depredation risk in Tanzania’s Ruaha landscape

Tanzania’s Ruaha landscape, centred around Ruaha National Park (RNP), is an international priority area for large carnivores, supporting >10% of the world’s lions (Panthera leo) and globally significant populations of leopards (Panthera pardus), spotted hyaenas (Crocuta crocuta) and other carnivores. However, Ruaha’s carnivore populations cause intense conflict with local people, mainly due to livestock depredation, and are exposed to alarming rates of retaliatory killing, especially on village land adjacent to RNP. Depredation risk is likely to be influenced by both habitat features and livestock husbandry, but the specific environmental risk factors, and relative importance of habitat and husbandry, have never been assessed in this landscape. Here, we assessed which ecogeographic variables (EGVs) were associated with depredation risk for grazing livestock on village land, and generated a predictive map of large carnivore predation risk, based on species distribution modelling algorithms (SDMs). Secondly, we investigated the relative influence of husbandry and EGVs on depredation risk of enclosed stock, based on a generalized linear model. Grazing livestock predation risk was higher closer to rivers, and in areas of lower elevation and low percentage of tree cover, with 41% of the area mapped as high-risk. For enclosed stock, predation risk was mostly influenced by low percentage of tree cover and increased rainfall, with no discernible influence of current husbandry, which suggests that traditional husbandry was insufficient to outweigh the innate predation risks associated with high-risk landscape areas. Adopting new husbandry methods, such as specialised guarding dogs and fortified livestock enclosures, could be valuable for reducing depredation and carnivore killing in the Ruaha landscape.

Hábitos alimentarios del pargo mancha &lt;i&gt;Lutjanus guttatus&lt;/i&gt; (Pisces: Lutjanidae) en Los Cóbanos y Puerto La Libertad, El Salvador

Abstract: A total of 175 spotted snapper Lutjanus guttatus were collected monthly in the Los Cobanos and Puerto La Libertad, El Salvador, from January to December 2000 to determine its feeding habits. The fishes studied ranged 9.8 - 58.0 cm in total length. Were collected using push-net and hook and line. This snapper is a bentonic opportunistic carnivorous predator. The total biomass of the stomach contents was 260.5 g. Crustaceans (Squillidae, Portunidae, Dynomenidae. Penaeidae, Sicyoniidae, Callianassidae), were the most abundant group: they accounted for 50.4% of the total biomass. Numerically, Portunus asper was the most abundant prey. Ontogenic differences were observed in the diet. In juveniles (16 cm TL). at any time of the year, the most frequent and abundant components were crustaceans and in adults were crustaceans, fishes and mollusks. The relative importance of different components of the diet was assessed with two indexes that combine. in different ways. percentage frequency of occurrence, percentage number and percentage weight of prey categories. The commercial use this resource and the absence of management strategies are discussed.