206 research outputs found
Revealing kleptoparasitic and predatory tendencies in an African mammal community using camera traps: a comparison of spatiotemporal approaches
Camera trap data are increasingly being used to characterise relationships between the spatiotemporal activity patterns of sympatric mammal species, often with a view to inferring inter-specific interactions. In this context, we attempted to characterise the kleptoparasitic and predatory tendencies of spotted hyaenas Crocuta crocuta and lions Panthera leo from photographic data collected across 54 camera trap stations and two dry seasons in Tanzania's Ruaha National Park. We applied four different methods of quantifying spatiotemporal associations, including one strictly temporal approach (activity pattern overlap), one strictly spatial approach (co-occupancy modelling), and two spatiotemporal approaches (co-detection modelling and temporal spacing at shared camera trap sites). We expected a kleptoparasitic relationship between spotted hyaenas and lions to result in a positive spatiotemporal association, and further hypothesised that the association between lions and their favourite prey in Ruaha, the giraffe Giraffa camelopardalis and the zebra Equus quagga, would be stronger than those observed with non-preferred prey species (the impala Aepyceros melampus and the dikdik Madoqua kirkii). Only approaches incorporating both the temporal and spatial components of camera trap data resulted in significant associative patterns. The latter were particularly sensitive to the temporal resolution chosen to define species detections (i.e. occasion length), and only revealed a significant positive association between lion on spotted hyaena detections, as well as a tendency for both species to follow each other at camera trap sites, during the dry season of 2013, but not that of 2014. In both seasons, observed spatiotemporal associations between lions and each of the four herbivore species considered provided no convincing or consistent indications of any predatory preferences. Our study suggests that, when making inferences on inter-specific interactions from camera trap data, due regards should be given to the potential behavioural and methodological processes underlying observed spatiotemporal patterns
Compromised survivorship in zoo elephants
Keeping elephants in zoos is extremely costly, yet does not yield self-sustaining 16 populations. In Europe, which holds c. half the global zoo elephant population, a long17 term decline of c.10% per year is expected in both species, if reliant on zoo-bred animals 18 under historically prevailing conditions. Fitness in zoos is compromised in several ways. 19 Compared with protected in situ populations (Burmese working Asians; Kenyan free20 living Africans), zoo elephants show premature reproductive senescence and -- despite 21 improving adult survivorship for Africans -- die earlier in adulthood than expected. In 22 Asian elephants, infant survivorship in zoos is also greatly reduced relative to Burmese 23 elephants, and furthermore, zoo-born animals die earlier in adulthood than wild-caught 24 conspecifics kept in zoos, via effects ‘programmed’ peri-natally. In this species, being 25 transferred between zoos also increases mortality rates. Both survival and fecundity 26 would need to improve to attain self-sustaining zoo populations. Our findings 27 demonstrate deficits in zoo elephant management, particularly for Asians, and implicate 28 stress and obesity as likely problems
Strict protected areas are essential for the conservation of larger and threatened mammals in a priority region of the Brazilian Cerrado
ssessing protected area (PA) effectiveness is key to ensure the objectives of habitat protection are being achieved. There is strong evidence that legal protection reduces loss of natural vegetation, but biodiversity loss can still happen without significant changes in vegetation cover. Here we use data from a specifically designed camera trap survey to conduct a counterfactual assessment of PA effectiveness at safeguarding local biodiversity in the Brazilian Cerrado. We surveyed the mammal community in 517 locations at the Sertão Veredas-Peruaçu mosaic, distributed across five strict PAs (264 survey sites in five arrays) and two multiple-use PAs with low management levels (253 survey sites in four arrays). We adopted a multi-species occupancy framework to analyse our dataset while also controlling for confounding factors not directly related to protection. Of the 21 species assessed, nine had higher occupancy in strict PAs, one had higher occupancy in multiple-use PAs, and ten did not respond to protection level. Site species richness was nearly twice as large in areas under stricter protection, with even greater differences for species richness of globally threatened and larger mammals (>15 kg). Overall we demonstrated that the strict PAs surveyed support higher mammal diversity than similar areas under less restrictive management, with a particular strong effect on larger and threatened species. Given that strict PAs cover only 3% of the Cerrado, our results suggest that expanding the area under strict protection is likely to benefit iconic species of the Brazilian savanna, such as the maned wolf and giant anteater
Monitoring wild animal communities with arrays of motion sensitive camera traps
Studying animal movement and distribution is of critical importance to addressing environmental challenges including invasive species, infectious diseases, climate and land-use change. Motion sensitive camera traps offer a visual sensor to record the presence of a broad range of species providing location -specific information on movement and behavior. Modern digital camera traps that record video present new analytical opportunities, but also new data management challenges. This paper describes our experience with a terrestrial animal monitoring system at Barro Colorado Island, Panama. Our camera network captured the spatio-temporal dynamics of terrestrial bird and mammal activity at the site - data relevant to immediate science questions, and long-term conservation issues. We believe that the experience gained and lessons learned during our year long deployment and testing of the camera traps as well as the developed solutions are applicable to broader sensor network applications and are valuable for the advancement of the sensor network research. We suggest that the continued development of these hardware, software, and analytical tools, in concert, offer an exciting sensor-network solution to monitoring of animal populations which could realistically scale over larger areas and time spans
Variance of bioimpedance analysis measurements with physicalactivity and ingestion of food and water
[resumo][abstract
Does polymorphism make Asiatic golden cat the most adaptable predator in Eastern Himalayas?
Some wild felines have a diverse range of coat colors while others do not. Jaguars and leopards, for instance, come in spotted and melanistic forms but tigers are always striped and lions always beige. Smaller cats like clouded leopards, marbled cats, and ocelots are almost always patterned in the same way while jaguarundis, oncillas, and golden cats occur in several different colors and patterns. This article is protected by copyright. All rights reserved
Quantifying levels of animal activity using camera-trap data
1. Activity level (the proportion of time that animals spend active) is a behavioural and ecological metric that can provide an indicator of energetics, foraging effort and exposure to risk. However, activity level is poorly known for free-living animals because it is difficult to quantify activity in the field in a consistent, cost-effective and non-invasive way. 2. This paper presents a new method to estimate activity level with time-of-detection data from camera-traps (or more generally any remote sensors), fitting a flexible circular distribution to these data in order to describe the underlying activity schedule, and calculating overall proportion of time active from this. 3. Using simulations and a case study for a range of small to medium-sized mammal species, we find that activity level can reliably be estimated using the new method. 4. The method depends on the key assumption that all individuals in the sampled population are active at the peak of the daily activity cycle. We provide theoretical and empirical evidence suggesting that this assumption is likely to be met for many species, but may be less likely in large predators, or in high latitude winters. Further research is needed to establish stronger evidence on the validity of this assumption in specific cases, however, the approach has the potential to provide an effective, non invasive alternative to existing methods for quantifying population activity levels
Measuring social-emotional development in middle childhood: the Middle Years Development Instrument
This paper discusses the conceptualization, development, validation, and application of the Middle Years Development Instrument (MDI) – a population-based child self-report tool that assesses children\u27s social-emotional development and well-being in the context of their home, school, and neighborhood. The MDI is administered at a population-level to 4th and 7th grade students within participating public school districts across British Columbia, Canada. Children respond to items in five domains: (1) social-emotional development, (2) connectedness to peers and adults, (3) school experiences, (4) physical health and well-being, and (5) constructive use of after-school time. Results are aggregated for schools and communities and reported back in comprehensive reports and community maps to inform planning and decision making at local and regional levels. Shared testimonials exemplify how MDI results have been used by educators, community organizers, and city planners as a catalyst for promoting children\u27s social and emotional competence and facilitating collaboration between schools and communities
Prior Mating Experience Modulates the Dispersal of Drosophila in Males More Than in Females
Cues from both an animal’s internal physiological state and its local environment may influence its decision to disperse. However, identifying and quantifying the causative factors underlying the initiation of dispersal is difficult in uncontrolled natural settings. In this study, we automatically monitored the movement of fruit flies and examined the influence of food availability, sex, and reproductive status on their dispersal between laboratory environments. In general, flies with mating experience behave as if they are hungrier than virgin flies, leaving at a greater rate when food is unavailable and staying longer when it is available. Males dispersed at a higher rate and were more active than females when food was unavailable, but tended to stay longer in environments containing food than did females. We found no significant relationship between weight and activity, suggesting the behavioral differences between males and females are caused by an intrinsic factor relating to the sex of a fly and not simply its body size. Finally, we observed a significant difference between the dispersal of the natural isolate used throughout this study and the widely-used laboratory strain, Canton-S, and show that the difference cannot be explained by allelic differences in the foraging gene
WiseEye: next generation expandable and programmable camera trap platform for wildlife research
Funding: The work was supported by the RCUK Digital Economy programme to the dot.rural Digital Economy Hub; award reference: EP/G066051/1. The work of S. Newey and RJI was part funded by the Scottish Government's Rural and Environment Science and Analytical Services (RESAS). Details published as an Open Source Toolkit, PLOS Journals at: http://dx.doi.org/10.1371/journal.pone.0169758Peer reviewedPublisher PD
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