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The illegal wildlife trade (IWT) is one of the largest global crime economies, directly threatening species and their habitats, and biodiversity, and indirectly the global climate, and countries' economies. Syndicates operating within the IWT are often involved in trafficking of humans, weapons, and drugs. IWT takes place in large scale through international ports, with wildlife being smuggled inside shipping containers. Current methods to combat IWT and screen these shipping containers, such as X-ray scans, are expensive and time-consuming. Scent-detection animals present an innovative approach to combatting IWT, as animals may be better suited to distinguish between organic materials and less susceptible to visual concealment methods. Previous scent-detection work has largely focused on conservation dogs (Canis lupus familiaris). Here, we present a series of proof-of-principle studies training African giant pouched rats (Cricetomys ansorgei) to detect illegally trafficked wildlife. As initial proof-of-principle within a controlled laboratory environment, we trained rats (n=11) to detect the scent of pangolin scales (Manis spp.) and a threatened African hardwood (Dalbergia melanoxylon). In subsequent experiments, we trained these rats (n=10) to detect rhinoceros horn (family Rhinocerotidae), and elephant tusks (Loxodonta spp.). At the conclusion of these studies, rats (n=7) accurately identified all four target species (although ivory samples may have been cross-contaminated, and results should be interpreted with caution) while correctly rejecting non-target items commonly used by traffickers to conceal the presence of illicit material. Rats detected the presence of wildlife targets even when these were concealed in mixtures among non-target items. These results provide the foundation to train rats for scent-detection of illegally trafficked wildlife to combat IWT. The unique attributes of rats could allow them to complement existing screening technologies in the fight against IWT. Rats have low training and maintenance costs, flexibly work with multiple handlers, have a long lifespan, and a sophisticated sense of smell. Their small size also offers unique capabilities for the screening of shipping containers, such as being able to navigate densely packed areas or be lifted to assess contents of sealed containers by screening ventilation systems. Future directions include assessing operational feasibility of deploying rats at ports. [ABSTRACT FROM AUTHOR]

Behaviour has a significant heritable component; however, unpicking the variants of interest in the neural circuits and molecular pathways that underpin these has proven difficult. Here, we present a comprehensive analysis of the relationship between known and new candidate genes from identified pathways and key behaviours for survival in 109 adult rhesus macaques (Macaca mulatta). Eight genes involved in emotion were analysed for variation at a total of nine loci. Genetic data were then correlated with cognitive and observational measures of behaviour associated with wellbeing and survival using MCMC-based Bayesian GLMM in R, to account for relatedness within the macaque population. For four loci the variants genotyped were length polymorphisms (SLC6A4 5-hydroxytryptamine transporter length-polymorphic repeat (5-HTTLPR), SLC6A4 STin polymorphism, Tryptophan 5-hydroxylase 2 (TPH2) and Monoamine oxidase A (MAOA)) whilst for the other five (5-hydroxytryptamine receptor 2A (HTR2A), Dopamine Receptor D4 (DRD4), Oxytocin receptor (OXTR), Arginine vasopressin receptor 1A (AVPR1a), Opioid receptor mu(μ) 1 (OPRM1)) SNPs were analysed. STin genotype, DRD4 haplotype and OXTR haplotype were significantly associated with the cognitive and observational measures of behaviour associated with wellbeing and survival. Genotype for 5-HTTLPR, STin and AVPR1a, and haplotype for HTR2A, DRD4 and OXTR were significantly associated with the duration of behaviours including fear and anxiety. Understanding the biological underpinnings of individual variation in negative emotion (e.g., fear and anxiety), together with their impact on social behaviour (e.g., social attention including vigilance for threat) has application for managing primate populations in the wild and captivity, as well as potential translational application for understanding of the genetic basis of emotions in humans. [ABSTRACT FROM AUTHOR]

Context: Wildlife tourism has been shown to increase stress in a variety of species and can negatively affect survival, reproduction, welfare, and behaviour of individuals. In African elephants, Loxodonta africana, increased physiological stress has been linked to use of refugia, rapid movement through corridors, and heightened aggression towards humans. However, we are unaware of any studies assessing the impact of tourism pressure (tourist numbers) on physiological stress in elephants. Aims: We used faecal glucocorticoid metabolite (fGCM) concentrations to investigate whether tourist numbers in Madikwe Game Reserve, South Africa, were related to changes in physiological stress in elephants. Methods: We repeatedly collected dung samples (n = 43) from 13 individually identified elephants over 15 months. Using a generalised linear mixed model and a Kenward–Roger approximation, we assessed the impact of monthly tourist numbers, season, age, and sex on elephant fGCM concentrations. Key results: High tourist numbers were significantly related to elevated fGCM concentrations. Overall, fGCM concentrations increased by 112% (from 0.26 to 0.55 µg g−1 dry weight) in the months with the highest tourist pressure, compared to months with the lowest tourist pressure. Conclusions: Managers of fenced reserves should consider providing potential alleviation measures for elephants during high tourist pressure, for example, by ensuring that refuge areas are available. This may be of even higher importance if elephant populations have had traumatic experiences with humans in the past, such as poaching or translocation. Such management action will improve elephant welfare and increase tourist safety. Implications: Although tourism can generate substantial revenue to support conservation action, careful monitoring of its impact on wildlife is required to manage potential negative effects. Wildlife tourism can increase stress in a variety of species and affect welfare and behaviour. We assessed whether wildlife tourism affected physiological stress levels of African elephants and found that greater tourist numbers were positively correlated with stress. Reserve managers should provide potential alleviation measures for elephants during periods of high tourist pressure, for example, by ensuring that refuge areas are available. Photograph by Isabelle Szott. [ABSTRACT FROM AUTHOR]

Conservation biologists can use hormone measurements to assess animals' welfare, reproductive state, susceptibility to stressors, as well as energy expenditure. Quantifying hormone concentrations from faecal samples is particularly advantageous as samples can be collected without disturbing animals' behaviour. In order for an endocrine marker to be useful for wildlife managers, we need to understand how extrinsic and intrinsic factors affect hormone concentrations in free-ranging animal populations. Thyroid hormones are linked to basal metabolic rate and energy expenditure. Previous research demonstrated that triiodothyronine (T3) can be measured successfully in faecal matter of African elephants, Loxodonta africana. However, to our knowledge, research into factors affecting changes in elephant T3 levels has only been carried out in captive elephants so far. Thus, we present the first study of faecal T3 metabolite (mT3) concentrations of a large population of free-ranging African elephants. Over 15 months, we collected faecal samples from identified (n  = 43 samples) and unidentified (n  = 145 samples) individuals in Madikwe Game Reserve, South Africa. We investigated whether vegetative productivity [normalized difference vegetation index (NDVI)] in interaction with mean monthly temperature, age and sex affected mT3 concentrations. We found a significant negative interaction effect of NDVI and temperature. Increasing NDVI was related to higher concentrations of mT3, but increasing temperature was related to a decrease in mT3 concentrations in individually identified and unidentified elephants. In unidentified individuals, juvenile elephants had significantly higher mT3 concentrations compared to adult elephants. Faecal T3 can successfully be quantified in samples from free-ranging elephant populations and thus provides insight into energy expenditure in large herbivores. [ABSTRACT FROM AUTHOR]