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Prey remains found in carnivore scats provide generalised dietary profiles of sampled populations. The profile may be biased if individual diets differ and some individuals are over- or under-represented in the sample. Quantifying individual contributions allows us to recognise these potential biases and better interpret generalised profiles. Knowing the dietary differences or similarity between individuals can help us to understand selection pressures and identify drivers of distribution and abundance. Using the results of individual faecal genotyping, we re-interpreted our previously-published generalised dietary profile of an elusive, neotropical felid, the jaguar (Panthera onca; Foster et al. (2010)). We quantified individual sample sizes, assessed whether the generalised profile was influenced by the inclusion of scats originating from the same individual and prey carcass (pseudo-replication), and quantified the distribution of prey species among individuals. From an original sample of 322 jaguar scats from a high-density jaguar population in Belize, we identified 206 prey items (individual prey animals) in 176 independent scats representing 32 jaguars (26 males, 3 females, 3 unknown sex). The influence of pseudo-replication in the original dietary profile was minimal. The majority of scats (94%) came from male jaguars. Eight males accounted for two-thirds of the prey items, while 24 jaguars each contributed <5% of the prey items. With few exceptions, the jaguars followed the same broad diet, a 2:1:1 ratio of nine-banded armadillos (Dasypus noveminctus), other vertebrates ≤10kg, and ungulates, primarily peccaries (Tayassu pecari and Pecari tajacu). We noted prey switching between wild and domestic ungulates for individuals spanning protected forests and farmland. This first scat-based study exploring individual variation in jaguar diet highlights the importance of armadillos and peccaries for male jaguars in Belize, the need for research on their roles in supporting high-density jaguar populations, and the need for more data on female diet from across the jaguar range. [ABSTRACT FROM AUTHOR]

Camera trapping is the standard field method of monitoring cryptic, low-density mammal populations. Typically, researchers run camera surveys for 60 to 90 days and estimate density using closed population spatially explicit capture-recapture (SCR) models. The SCR models estimate density, capture probability (g0), and a scale parameter (σ) that reflects ranging behaviour. We used a year of camera data from 20 camera stations to estimate the density of male jaguars (Panthera onca) in the Cockscomb Basin Wildlife Sanctuary in Belize, using closed population SCR models. We subsampled the dataset into 276 90-day sessions and 186 180-day sessions. Estimated density fluctuated from 0.51 to 5.30 male jaguars / 100 km2 between the 90-day sessions, with comparatively robust and precise estimates for the 180-day sessions (0.73 to 3.75 male jaguars / 100 km2). We explain the variation in density estimates from the 90-day sessions in terms of temporal variation in social behaviour, specifically male competition and mating events during the three-month wet season. Density estimates from the 90-day sessions varied with σ, but not with the number of individuals detected, suggesting that variation in density was almost fully attributable to changes in estimated ranging behaviour. We found that the models overestimated σ when compared to the mean ranging distance derived from GPS tracking data from two collared individuals in the camera grid. Overestimation of σ when compared to GPS collar data was more pronounced for the 180-day sessions than the 90-day sessions. We conclude that one-off ('snap-shot') short-term, small-scale camera trap surveys do not sufficiently sample wide-ranging large carnivores. When using SCR models to estimate the density from these data, we caution against the use of poor sampling designs and/or misinterpretation of scope of inference. Although the density estimates from one-off, short-term, small-scale camera trap surveys may be statistically accurate within each short-term sampling period, the variation between density estimates from multiple sessions throughout the year illustrate that the estimates obtained should be carefully interpreted and extrapolated, because different factors, such as temporal stochasticity in behaviour of a few individuals, may have strong repercussions on density estimates. Because of temporal variation in behaviour, reliable density estimates will require larger samples of individuals and spatial recaptures than those presented in this study (mean +/- SD = 14.2 +/- 1.2 individuals, 37.7 +/- 4.7 spatial recaptures, N = 276 sessions), which are representative of, or higher than published sample sizes. To satisfy the need for larger samples, camera surveys will need to be more expansive with a higher density of stations. In the absence of this, we advocate longer sampling periods and subsampling through time as a means of understanding and describing stability or variation between density estimates. [ABSTRACT FROM AUTHOR]

Communication is an integral part of animal behavior, impacting population structure and individual fitness and regulating spatial distributions. Scent marking is common among solitary, low-density, and wide-ranging carnivores, such as felids. Understanding the functional role of scent marking will inform our understanding of the behavioral ecology of carnivores. We investigated patterns of scent marking by pumas (Puma concolor) and jaguars (Panthera onca) via weekly surveys of trails for scrapes and documenting scent-marking behaviors and responses using motion-triggered video cameras. Jaguars mainly sprayed vegetation, whereas pumas mainly scraped the ground. Only a subset of individuals for both pumas and jaguars were responsible for the majority of scent-marking activity. On average, male pumas scraped more frequently (scrapes/km) than male jaguars, and the scrape rate of male pumas increased following the presence of potential mates and competitors. Male pumas returned to trails more quickly following the presence of conspecifics (potential competitors or mates) than in their absence, however, visitation by male jaguars increased in response to competitors only. A male puma detected travelling with three different females on separate occasions scraped more frequently than males who were not detected with females. This study suggests that jaguars and pumas are constantly assessing, and reacting to, the presence and marks of competitors and potential mates, facilitating the maintenance of complex social structures. La comunicación es una parte integral del comportamiento animal; la cual impacta la estructura de la población, la aptitud de adaptación individual y regula la distribución espacial. La marcación olfativa es común entre los carnívoros solitarios, de baja densidad y amplia distribución, como los felinos. El entender el papel funcional de la marcación con olores, informa nuestra comprensión de la ecología del comportamiento de los carnívoros. Investigamos los patrones de marcación de olor por pumas (Puma concolor) y jaguares (Panthera onca) a través de muestreos semanales de senderos con rastros de rasguños, documentando los comportamientos y respuestas de marcación de olor utilizando cámaras de video activadas por movimiento. Los jaguares rociaban principalmente la vegetación, mientras que los pumas predominantemente hicieron rasguños en el suelo. Solo un subconjunto de individuos, tanto de pumas como de jaguares, fueron responsables de la mayoría de la actividad de marcación de olores. En promedio, los pumas machos rasguñaron con mayor frecuencia (rasguños /km) que los jaguares machos, y la tasa de rasguñar se incrementó luego de la presencia de parejas potenciales y de competidores. Los pumas machos regresaron a los senderos más rápidamente siguiendo la presencia de con-específicos (potenciales parejas o competidores) que en su ausencia; sin embargo, la visita de jaguares machos se incrementó sólo en respuesta a los competidores. Un puma macho que se detectó viajando con tres hembras diferentes en distintas ocasiones, rasguñaba con mayor frecuencia que los machos que no fueron detectados con hembras. Este estudio sugiere que jaguares y pumas, constantemente están evaluando y reaccionando, a la presencia y las marcas de las potenciales parejas y competidores, facilitando el mantenimiento de estructuras sociales complejas. [ABSTRACT FROM AUTHOR]

In this study, we estimate life history parameters and abundance for a protected jaguar population using camera-trap data from a 14-year monitoring program (2002–2015) in Belize, Central America. We investigated the dynamics of this jaguar population using 3,075 detection events of 105 individual adult jaguars. Using robust design open population models, we estimated apparent survival and temporary emigration and investigated individual heterogeneity in detection rates across years. Survival probability was high and constant among the years for both sexes (φ = 0.78), and the maximum (conservative) age recorded was 14 years. Temporary emigration rate for the population was random, but constant through time at 0.20 per year. Detection probability varied between sexes, and among years and individuals. Heterogeneity in detection took the form of a dichotomy for males: those with consistently high detection rates, and those with low, sporadic detection rates, suggesting a relatively stable population of ‘residents’ consistently present and a fluctuating layer of ‘transients’. Female detection was always low and sporadic. On average, twice as many males than females were detected per survey, and individual detection rates were significantly higher for males. We attribute sex-based differences in detection to biases resulting from social variation in trail-walking behaviour. The number of individual females detected increased when the survey period was extended from 3 months to a full year. Due to the low detection rates of females and the variable ‘transient’ male subpopulation, annual abundance estimates based on 3-month surveys had low precision. To estimate survival and monitor population changes in elusive, wide-ranging, low-density species, we recommend repeated surveys over multiple years; and suggest that continuous monitoring over multiple years yields even further insight into population dynamics of elusive predator populations. [ABSTRACT FROM AUTHOR]

Densities of elusive terrestrial mammals are commonly estimated from camera-trap data. Typically, this is a 2-step process involving 1) fitting conventional closed population capture-recapture models to estimate abundance, and 2) using ad hoc methods to determine the effective trapping area. The methodology needs to be accurate, robust, and reliable when results are used to guide wildlife management. We critically review 47 published studies and discuss the problems associated with contemporary population estimates of elusive species from camera-trap data. In particular we discuss 1) individual identification, 2) sample size and capture probability, 3) camera location and spacing, 4) the size of the study area, and 5) ad hoc density estimation from the calculation of an effective trapping area. We also discuss the recently developed spatially explicit capture-recapture (SECR) models as an alternative approach that does not require the intermediate step of estimating an effective trapping area. We recommend 1) greater transparency in study design and quality of the data, 2) greater rigor when reviewing manuscripts, and 3) that more attention is given to the survey design to ensure data are of sufficient quality for analysis. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Abstract: Activity patterns of top predators are adapted for efficient predation, whereas their prey must contend with the conflicting demands of acquiring resources and avoiding predators. Here we analyse the activity of jaguars (Panthera onca) and pumas (Puma concolor) in relation to their most important prey species, armadillos (Dasypus novemcinctus) and pacas (Agouti paca) respectively, in the Cockscomb Basin Wildlife Sanctuary, Belize using large-scale camera-trap data. Jaguars and pumas have similar 24h activity patterns as armadillos and pacas, both burrow-dwelling species, and negligible overlap with less frequently consumed prey species such as red brocket deer (Mazama americana) and peccaries. Activity of armadillos and pacas varied with moon phase, with reduced activity during periods of brighter illumination, perhaps as a predator-avoidance strategy. Across the study area, moon phase had no overall influence on jaguar and puma activity; however at locations associated with armadillos, jaguar activity declined with brighter illumination, perhaps indicating a shift to alternative prey during full moon when armadillos avoided foraging above ground. No such relationship was found for pumas and moon phase at locations associated with pacas. [Copyright &y& Elsevier]

Marking behaviors of jaguars (Panthera onca) and pumas (Puma concolor) were investigated by linking sign from transect surveys to species, sex, and individual detected by camera traps along trails in the Cockscomb Basin Wildlife Sanctuary, Belize. The most commonly encountered big-cat signs were scrape marks. These were produced by cats raking the ground with their feet. Scrapes were associated more strongly with presence of male pumas than with female pumas or jaguars of either sex. Scats found in scrapes were genotyped to species level and indicated that jaguars produced larger scrapes than pumas and that pumas were more likely to scrape with their hind feet than with front feet. Scrapes were spatially clustered along trails, indicating that individuals scrape in response to other scrapes in the same area. High scraping frequencies were not associated with the presence of specific individuals, suggesting that scrape-marking behavior does not signal dominance in this area. [ABSTRACT FROM AUTHOR]

The article focuses on sample-size effects on diet analysis from scats of jaguars and pumas. The impact of sample size on the number of taxa found in the diets of jaguars and pumas and the precision of estimates of the relative occurrence of common prey animals in jaguar and puma diets are studied. The study shows that the best sample size for diet analysis of the animals is at least 70 to 100 scats. Half of the recommended sample size will detect the primary prey but is unreliable for relative occurrence.

We used extensive camera-trap surveys to study interindividual interactions among individually recognizable jaguars (Panthera onca) and plain-colored pumas (Puma concolor). Timed location data from a network of 119 trap stations in the Cockscomb Basin of Belize provide the 1st evidence of interspecific avoidance calibrated against intraspecific interactions among jaguars. Camera trapping has advantages over radiotelemetry in its potential to provide data on the complete array of individuals within the study area. The 23 individually identified male jaguars showed high levels of overlap in ranges, with up to 5 different males captured at the same location in the same month. Low levels of avoidance between individuals and a high flux of individuals contributed to low consistency in home-range ownership over the long term (3 months to 2 years). Jaguars and pumas had similar nocturnal activity schedules. Both species used similar habitats within the Cockscomb Basin, indicated by a high correlation in capture rates per location between species. Apart from their overall spatial similarities, jaguars and pumas avoided using the same location at the same time. This interspecific segregation was detectable over and above the spatial and temporal segregation of individual jaguars. [ABSTRACT FROM AUTHOR]

Population assessments of wide-ranging, cryptic, terrestrial mammals rely on camera trap surveys. While camera trapping is a powerful method of detecting presence, it is difficult distinguishing rarity from low detection rate. The margay (Leopardus wiedii) is an example of a species considered rare based on its low detection rates across its range. Although margays have a wide distribution, detection rates with camera traps are universally low; consequently, the species is listed as Near Threatened. Our 12-year camera trap study of margays in protected broadleaf forest in Belize suggests that while margays have low detection rate, they do not seem to be rare, rather that they are difficult to detect with camera traps. We detected a maximum of 187 individuals, all with few or no recaptures over the years (mean = 2.0 captures/individual ± SD 2.1), with two-thirds of individuals detected only once. The few individuals that were recaptured across years exhibited long tenures up to 9 years and were at least 10 years old at their final detection. We detected multiple individuals of both sexes at the same locations during the same survey, suggesting overlapping ranges with non-exclusive territories, providing further evidence of a high-density population. By studying the sparse annual datasets across multiple years, we found evidence of an abundant margay population in the forest of the Cockscomb Basin, which might have been deemed low density and rare, if studied in the short term. We encourage more long-term camera trap studies to assess population status of semi-arboreal carnivore species that have hitherto been considered rare based on low detection rates. [ABSTRACT FROM AUTHOR]

Quantifying the distribution of daily activity is an important component of behavioral ecology. Historically, it has been difficult to obtain data on activity patterns, especially for elusive species. However, the development of affordable camera traps and their widespread usage has led to an explosion of available data from which activity patterns can be estimated.Continuous‐time spatial capture–recapture (CT SCR) models drop the occasion structure seen in traditional spatial and nonspatial capture–recapture (CR) models and use the actual times of capture. In addition to estimating density, CT SCR models estimate expected encounters through time. Cyclic splines can be used to allow flexible shapes for modeling cyclic activity patterns, and the fact that SCR models also incorporate distance means that space–time interactions can be explored. This method is applied to a jaguar dataset.Jaguars in Belize are most active and range furthest in the evening and early morning and when they are located closer to the network of trails. There is some evidence that females have a less variable pattern than males. The comparison between sexes demonstrates how CT SCR can be used to explore hypotheses about animal behavior within a formal modeling framework.SCR models were developed primarily to estimate and model density, but the models can be used to explore processes that interact across space and time, especially when using the CT SCR framework that models the temporal dimension at a finer resolution. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the articles "What is Conservation Science?" by P. Kareiva and M. Marvier in a 2012 issue and "Humanity's Domination of Nature Is Part of the Problem: A Response to Kareiva and Marvier" by R. Noss, R. Nash, P. Paquet, and M. Soulé in a 2013 issue.

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. [ABSTRACT FROM AUTHOR]

Open population capture‐recapture models are widely used to estimate population demographics and abundance over time. Bayesian methods exist to incorporate open population modeling with spatial capture‐recapture (SCR), allowing for estimation of the effective area sampled and population density. Here, open population SCR is formulated as a hidden Markov model (HMM), allowing inference by maximum likelihood for both Cormack‐Jolly‐Seber and Jolly‐Seber models, with and without activity center movement. The method is applied to a 12‐year survey of male jaguars (Panthera onca) in the Cockscomb Basin Wildlife Sanctuary, Belize, to estimate survival probability and population abundance over time. For this application, inference is shown to be biased when assuming activity centers are fixed over time, while including a model for activity center movement provides negligible bias and nominal confidence interval coverage, as demonstrated by a simulation study. The HMM approach is compared with Bayesian data augmentation and closed population models for this application. The method is substantially more computationally efficient than the Bayesian approach and provides a lower root‐mean‐square error in predicting population density compared to closed population models. [ABSTRACT FROM AUTHOR]

Ocelots (Leopardus pardalis) are listed as least concern on the International Union for Conservation of Nature (IUCN) Red list of Threatened Species, yet we lack knowledge on basic demographic parameters across much of the ocelot's geographic range, including population density. We used camera‐trapping methodology and spatially explicit capture‐recapture (SECR) models with sex‐specific detection function parameters to estimate ocelot densities across 7 field sites over 1 to 12 years (from data collected during 2002–2015) in Belize, Central America. Ocelot densities in the broadleaf rainforest sites ranged between 7.2 and 22.7 ocelots/100 km2, whereas density in the pine (Pinus spp.) forest site was 0.9 ocelots/100 km2. Applying an inverse‐variance weighted average over all years for each broadleaf site increased precision and resulted in average density ranging from 8.5 to 13.0 ocelots/100 km2. Males often had larger movement parameter estimates and higher detection probabilities at their activity centers than females. In most years, the sex ratio was not significantly different from 50:50, but the pooled sex ratio estimated using an inverse weighted average over all years indicated a female bias in 1 site, and a male bias in another. We did not detect any population trends as density estimates remained relatively constant over time; however, the power to detect such trends was generally low. Our SECR density estimates were lower but more precise than previous estimates and indicated population stability for ocelots in Belize. © 2018 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We used camera‐trapping methodology and spatially explicit capture‐recapture (SECR) models with sex‐specific detection function parameters to estimate ocelot densities across 7 field sites in Belize, Central America, 2002–2015. Except for the pine forest site, which appears to have naturally very low ocelot densities, we found no evidence that densities varied within or among the other predominantly broadleaf sites. Ocelots appear stable across sites, and more importantly, stable through time at our long‐term sites. [ABSTRACT FROM AUTHOR]

Abstract: Evaluating range‐wide habitat use by a target species requires information on species occurrence over broad geographic regions, a process made difficult by species rarity, large spatiotemporal sampling domains and imperfect detection. We address these challenges in an assessment of habitat use for jaguars (Panthera onca) outside protected areas in Central America. Occurrence records were acquired within 12 putative corridors using interviews with knowledgeable corridor residents. We developed a Bayesian hierarchical occupancy model to gain robust inference, allowing for heterogeneity introduced in the sampling process over space and time, using records of jaguar occurrence prone to false positives and false negatives. Probability of false detection of jaguars increased with the number of interviews conducted per unit (from 5.42% to 7.74% given <4 and ≥4 observers per unit). True probability of detection (p = 0.58) increased with the number of days interviewees spent in a survey unit per year. Failing to account for false positives biased predicted habitat use high (c. 1.8×), especially where occurrence records were sparse. Probability of site use by jaguars increased with greater forest cover, prey richness, and distance from human settlements, and decreased with greater agricultural cover, elevation, and distance from protected areas. Site use probabilities averaged 0.15–0.97 by corridor, providing relatively fine‐scale resolution of predicted jaguar occurrence consistent with known patterns of jaguar gene flow across Central America. Model validation, accounting for both false positives and negatives in the observation process, indicated moderate correspondence between model‐predicted observations and actual observations for withheld data (0.65, 95% CRI 0.59–0.71), with sensitivity and specificity rates of 0.69 (0.61–0.77) and 0.59 (0.50–0.68), respectively. These results demonstrate that reliable predictions can be achieved despite the complexity of large‐scale, interview‐based analyses of species occurrence. Synthesis and applications. Our Bayesian hierarchical occupancy model accommodated heterogeneity caused by typical sampling inequities and idiosyncrasies associated with interview data, yielding robust estimates of jaguar habitat use. Our approach is applicable to any wide‐ranging and readily identifiable species and has particular utility for rare species in human‐dominated landscapes where traditional survey techniques (e.g. camera traps) may be impractical. [ABSTRACT FROM AUTHOR]

Habitat loss and fragmentation present major challenges for wildlife conservation since connectivity between suitable habitat patches is needed for dispersal, allowing for genetic exchange between populations. These exchanges can be particularly important in marginal habitats as they ensure the persistence of populations that are often most vulnerable to natural occurrences or anthropogenic activities. Medium-sized mammals can be particularly susceptible to changes in the landscape and their absence can be an indicator of habitat degradation. In this study, 6 pacas (Cuniculus paca), medium-sized mammals that are an important prey of large felids and a popular game species for hunters in Belize, were radiotracked in the Central Belize Corridor. Home range estimates for these were larger than those documented for pacas inhabiting broadleaf forests of Panama and Costa Rica. When broadleaf habitats were inaccessible due to flooding, pacas selected a savannah habitat with dense vegetation over more open grass savannahs. Knowledge of how pacas and other wildlife use the landscape in the wildlife corridor will allow more effective management by guiding the development of adequate regulations for hunting and resource exploitation. [ABSTRACT FROM AUTHOR]

Although many large mammals currently face significant threats that could lead to their extinction, resources for conservation are often scarce, resulting in the need to develop efficient plans to prioritize conservation actions. We combined several methods in spatial ecology to identify the distribution of the endangered Baird's tapir across its range from southern Mexico to northern Colombia. Twenty-eight habitat patches covering 23% of the study area were identified, harboring potentially 62% or more of the total population for this flagship species. Roughly half of the total area is under some form of protection, while most of the remaining habitat (~70%) occurs in indigenous/local communities. The network with maximum connectivity created from these patches contains at least one complete break (in Mexico between Selva El Ocote and Selva Lacandona) even when considering the most generous dispersal scenario. The connectivity analysis also highlighted a probable break at the Panama Canal and high habitat fragmentation in Honduras. In light of these findings, we recommend the following actions to facilitate the conservation of Baird's tapir: 1) protect existing habitat by strengthening enforcement in areas already under protection, 2) work with indigenous territories to preserve and enforce their land rights, and help local communities maintain traditional practices; 3) re-establish connections between habitat patches that will allow for connectivity across the species' distribution; 4) conduct additional noninvasive surveys in patches with little or no species data; and 5) collect more telemetry and genetic data on the species to estimate home range size, dispersal capabilities, and meta-population structure. [ABSTRACT FROM AUTHOR]