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Context Many institutions of wildlife management and their hunting constituents tend to value ungulates over large carnivores, in part due to financial incentives associated with ungulate hunting over carnivore hunting. This system benefits from mythology that presents large carnivores as competitors for antlered male ungulates most prized by the hunting community. Aims We explored puma (Puma concolor) foraging and prey selection in two study areas in the Rocky Mountains, USA, to test whether pumas were competing with human hunters for antlered elk (Cervus elaphus) and mule deer (Odocoileus hemionus). Methods We employed GPS technology to track pumas and document their prey. We measured population- and individual-level selection by comparing prey killed by pumas to two estimates of prey availability: (1) landscape-level as determined by annual agency game counts; and (2) total prey killed by marked pumas. Key results Pumas in both study systems killed small numbers of antlered elk and mule deer. Pumas exhibited avoidance of mature elk, instead strongly selecting for elk calves over any other age or sex class. Pumas in both systems also selected for mule deer fawns; however, they also exhibited small positive selection (Jacob’s index of 0.08 in CO and 0.11 in WY on a scale of 0.0–1.0) for antlered mule deer. Conclusions In terms of numbers killed, pumas were not a competitor with human hunters for either antlered species. In terms of prey selection, pumas showed that they may be greater competition for rare antlered mule deer but not for antlered elk. In both study sites, antlered elk and deer remained at levels at which they could perform their ecological functions. Implications Our results highlight the fact that the overhunting of large carnivores over competition for antlered ungulates is mostly unfounded; we should instead focus management, media attention and conservation science on disentangling the complex ecology driving localised declines of mule deer, elk and other important ungulate resources, many of which are anthropogenic in nature and can be addressed.

There are several alternative hypotheses about the effects of territoriality, kinship and prey availability on individual carnivore distributions within populations. The first is the land-tenure hypothesis, which predicts that carnivores regulate their density through territoriality and temporal avoidance. The second is the kinship hypothesis, which predicts related individuals will be clumped within populations, and the third is the resource dispersion hypothesis, which suggests that resource richness may explain variable sociality, spatial overlap or temporary aggregations of conspecifics. Research on the socio-spatial organization of animals is essential in understanding territoriality, intra- and interspecific competition, and contact rates that influence diverse ecology, including disease transmission between conspecifics and courtship behaviours. We explored these hypotheses with data collected on a solitary carnivore, the cougar (Puma concolor), from 2005 to 2012 in the Southern Yellowstone Ecosystem, Wyoming, USA. We employed 27 annual home ranges for 13 cougars to test whether home range overlap was better explained by land tenure, kinship, resource dispersion or some combination of the three. We found support for both the land tenure and resource dispersion hypotheses, but not for kinship. Cougar sex was the primary driver explaining variation in home range overlap. Males overlapped significantly with females, whereas the remaining dyads (F-F, M-M) overlapped significantly less. In support for the resource dispersion hypothesis, hunting opportunity (the probability of a cougar killing prey in a given location) was often higher in overlapping than in non-overlapping portions of cougar home ranges. In particular, winter hunt opportunity rather than summer hunt opportunity was higher in overlapping portions of female-female and male-female home ranges. Our results may indicate that solitary carnivores are more tolerant of sharing key resources with unrelated conspecifics than previously believed, or at least during periods of high resource availability. Further, our results suggest that the resource dispersion hypothesis, which is typically applied to social species, is applicable in describing the spatial organization of solitary carnivores.

Background: Niche differentiation may betray current, ongoing competition between two sympatric species or reflect evolutionary responses to historic competition that drove species apart. The best opportunity to test whether ongoing competition contributes to niche differentiation is to test for behavioral shifts by the subordinate competitor in controlled experiments in which the abundance of the dominant competitor is manipulated. Because these circumstances are difficult to coordinate in natural settings for wide-ranging species, researchers seize opportunities presented by species reintroductions. We tested for new competition between reintroduced wolves and resident cougars in the Southern Yellowstone Ecosystem to assess whether wolves might be impacting the realized niche of sympatric cougars. Results: Between 2002 and 2012, a period during which wolves increased from 15 to as high as 91 in the study area, cougars significantly increased the percentage of deer and decreased the percentage of elk in their diet in summer. Our top models explaining these changes identified elk availability, defined as the number of elk per wolf each year, as the strongest predictor of changing cougar prey selection. Both elk and deer were simultaneously declining in the system, though deer more quickly than elk, and wolf numbers increased exponentially during the same time frame. Therefore, we concluded that prey availability did not explain prey switching and that competition with wolves at least partially explained cougar prey switching from elk to deer. We also recorded 5 marked cougar kittens killed by wolves and 2 more that were killed by an undetermined predator. In addition, between 2005 and 2012, 9 adult cougars and 10 cougar kittens died of starvation, which may also be in part explained by competition with wolves. Conclusions: Direct interspecific predation and shifting cougar prey selection as wolves increased in the system provided evidence for competition between recolonizing wolves and resident cougars. Through competition, recolonizing wolves have impacted the realized niche of resident cougars in the Southern Yellowstone Ecosystem (SYE), and current resident cougars may now exhibit a realized niche more reflective of an era when these species were previously sympatric in the Yellowstone Ecosystem.

Olfactory communication among mammals remains poorly studied yet may be key to understanding their ecology. This is particularly true for mammalian carnivores, which rely extensively on scent marking for communication. Previous research suggests that carnivore latrines play a large role in both intra- and interspecific communication. Despite the apparent complexity of mammal use of latrines, little work has examined behavior patterns of species that visit latrines. We used motion-triggered video cameras to study use and behavior of mammals at ocelot ( Leopardus pardalis ) latrines in Costa Rica. We documented temporal patterns of use by the focal species (ocelots), diversity of mammalian species using latrines, and behaviors that occurred at these sites. Ocelots showed peaks in visitation every 60–67 days and a shorter gap between intersexual versus intrasexual visits, supporting the idea that ocelot latrines are used to communicate information about reproductive status. Fourteen terrestrial mammal species visited the latrines, and these species engaged in a variety of behaviors, including mark investigation, scent marking, and acceptance of scent marks. The complexity and frequency of behaviors by nonfocal species suggest that latrines may play as important a role in communication for these other species as they do for ocelots. La comunicacion olfativa entre mamiferos ha sido poco estudiada, sin embargo puede ser la clave para el entendimiento de su ecologia. Esto es particularmente cierto para mamiferos carnivoros quienes dependen extensivamente de el marcaje de rastros olfativos para su comunicacion. Estudios previos siguieren que las letrinas juegan un rol importante en la comunicacion intra- e inter-especifica. A pesar de la aparente complejidad del uso de letrinas por parte de mamiferos, pocos trabajos han examinado los patrones de comportamiento de las especies que las visitan. Utilizamos camaras de videos sensibles al movimiento para estudiar el uso y comportamiento de mamiferos en letrinas de ocelotes ( Leopardus pardalis ) en Costa Rica. Documentamos los patrones de uso temporal por parte de especies focales (ocelotes), la diversidad de especies de mamiferos y los comportamientos que ocurrieron en estos lugares. Los resultados indican que el uso por parte de los ocelotes muestran picos de visitas cada 60 a 67 dias y un intervalo mas corto para visitas inter-sexuales que para visitas intra-sexuales. Esto apoya la idea de que las letrinas de los ocelotes son utilizadas para comunicar estatus reproductivos. Un total de catorce mamiferos terrestres visitaron las letrinas y estas especies mostraron una variedad de comportamientos, incluyendo investigacion, marcaje y aceptacion de rastros olfativos. La complejidad y frecuencia de comportamientos por especies no focales, sugieren que las letrinas pueden jugar un rol importante en la comunicacion de otras especies como lo es para los ocelotes.

Predation is inherently risky, and Cougars (Puma concolor) are occasionally injured while hunting prey. Between 2001 and 2015, we documented the cause of death of 59 Cougars (22 subadults and 37 adults) in the Southern Yellowstone Ecosystem, Wyoming. Here we report on 2 animals (9% of subadult mortalities) killed as a result of complications after hunting North American Porcupines (Erethizon dorsatum). We also report an observation of a Cougar killed in Venezuela by quills of a Prehensile-tailed Porcupine (Coendou prehensilis). Porcupines may kill and wound more Cougars than previously suspected and may be an important cause of mortality, at least for subadult animals.

Publisher Summary It was into this chaos that the American team arrived with a simple objective: collect the best possible information on the ecology and population dynamics of Amur tigers as a basis for implementing effective conservation actions. Today, conservation activities focused on the Amur tiger are multi-faceted, broad-based, and implemented by a variety of organizations, both governmental and non-governmental. Some of the most successful programs are predicated on credible science and effective monitoring to inform the conservation process. This chapter explores the relationships and explains how research has informed and guided Amur tiger conservation over a 15-year period. The “traditional” approach to conservation used by many large organizations and donors is to collect initial information as a basis for developing and implementing conservation strategies. Surveys that provide fundamental knowledge about changes in abundance of tiger populations can guide conservation efforts. Conservation planning has become a highly developed process, and there have been numerous algorithms and in-depth research to identify priority landscapes for biodiversity conservation. There is a need for research and conservation to evolve in close alliance, in which the necessities of conservation define the research priorities, and the findings of the research inform and guide the conservation actions.

The Cougar (Puma concolor) is a cryptic species in which social learning or opportunity learning has yet to be documented in the wild. “Opportunity teaching” is teaching in which an animal creates opportunities for conspecifics to observe or participate in operant learning. We present video data on an observation of Cougar kittens exhibiting social learning and inefficiency and inexperience in attempting to kill a live Mule Deer (Odocoileus hemionus) fawn. Our observations provide evidence for the importance of maternal care and they help explain why Cougar kittens less than a year of age have low survival rates.

Radio transmitters containing motion-sensitive devices that changed the pulse rate (mode) in response to movement were evaluated as a means for studying activity of black bears (Ursus americanus). Two types of motion sensors were used: tip switches gave immediate indications of activity, whereas reset motion sensors extended the active mode signal for 5 min. Locational accuracy was less affected by reset sensors than tip switches, and reset sensors facilitated activity monitoring of weak or fading radio signals. Tip switches were more useful in making continuous judgements of activity, and may be used to differentiate types and degrees of activity. For both sensors true activity could be distinguished from comfort movements. Also, both motion-sensitive transmitters gave indications of activity that compared well with hourly movements of bears; these transmitters were more sensitive to localized movements than measurements between radio locations determined by triangulation and were more practical because only one observer was necessary. Motion sensors also gave more reliable indications of activity than changes in signal integrity.

Background The agents of spotted fevers in Latin America are Rickettsia rickettsii, R. parkeri, Rickettsia sp. strain Atlantic rainforest, and R. massiliae. In Continental Central America, R. rickettsii remains the only known pathogenic tick-borne rickettsia. In the present study, ticks were collected from wild mammals in natural areas of Belize. Besides providing new data of ticks from Belize, we investigated rickettsial infection in some of these ticks. Our results provide ticks harboring rickettsial agents for the first time in Central America. Methods Between 2010 and 2015, wild mammals were lived-trapped in the tropical broadleaf moist forests of central and southern Belize. Ticks were collected from the animals and identified to species by morphological and molecular analysis (DNA sequence of the tick mitochondrial 16S RNA gene). Some of the ticks were tested for rickettsial infection by molecular methods (DNA sequences of the rickettsial gltA and ompA genes). Results A total of 84 ticks were collected from 8 individual hosts, as follows: Amblyomma pacae from 3 Cuniculus paca; Amblyomma ovale and Amblyomma coelebs from a Nasua narica; A. ovale from an Eira Barbara; A. ovale, Amblyomma cf. oblongoguttatum, and Ixodes affinis from a Puma concolor; and A. ovale, A. coelebs, A. cf. oblongoguttatum, and I. affinis from two Panthera onca. Three rickettsial agents were detected: Rickettsia amblyommii in A. pacae, Rickettsia sp. strain Atlantic rainforest in A. ovale, and Rickettsia sp. endosymbiont in Ixodes affinis. Conclusions The present study provides unprecedented records of ticks harboring rickettsial agents in the New World. An emerging rickettsial pathogen of South America, Rickettsia sp. strain Atlantic rainforest, is reported for the first time in Central America. Besides expanding the distribution of 3 rickettsial agents in Central America, our results highlight the possible occurrence of Rickettsia sp. strain Atlantic rainforest-caused spotted fever human cases in Belize, since its possible vector, A. ovale, is recognized as one of the most important human-biting ticks in the Neotropical region.