8 research outputs found

    Does size matter for horny beetles? A geometric morphometric analysis of interspecific and intersexual size and shape variation in Colophon haughtoni Barnard, 1929, and C. kawaii Mizukami, 1997 (Coleoptera: Lucanidae)

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    Colophon is an understudied, rare and endangered stag beetle genus with all species endemic to isolated mountain peaks in South Africa’s Western Cape. Geometric morphometrics was used to analyse intersexual and interspecific variation of size and shape in the mandibles, heads, pronota and elytra of two sympatric species: Colophon haughtoni and Colophon kawaii. All measured structures showed significant sexual dimorphism, which may result from male-male competition for females. Female mandibles were too small and featureless for analysis, but male Colophon beetles possess large, ornate mandibles for fighting. Males had significantly larger heads and pronota that demonstrated shape changes which may relate to resource diversion to the mandibles and their supporting structures. Females are indistinguishable across species, but males were accurately identified using mandibles, heads and pronota. Male C. kawaii were significantly larger than C. haughtoni for all structures. These results support the species status of C. kawaii, which is currently in doubt due to its hybridisation with C. haughtoni. We also demonstrate the value of geometric morphometrics as a tool which may aid Colophon conservation by providing biological and phylogenetic insights and enabling species identification

    Effect of visitors on the behaviour of three Asian small‐clawed otters Aonyx cinereus

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    The Asian small‐clawed otter Aonyx cinereus is classified as Vulnerable by the International Union for Conservation of Nature Red List. The aim of this study was to evaluate the effects of the presence of visitors on the behavioural repertoire of three Asian small‐clawed otters at Cattolica Aquarium, Italy. Observational data sampling took place over two periods of 11 days each. The first period was in August when the Aquarium was open and there were visitors present (open period = OP). The second period was between September and October, on days when the Aquarium was closed to visitors (closed period = CP). Focal sampling was integrated with behaviour sampling during data collection. To evaluate the significant differences in frequency and duration of behaviours during the OP and CP periods, a Wilcoxon Signed Rank test was performed. The results of this study showed that the absence of visitors stimulated significant differences in frequency and duration of activity (such as ‘locomotion’ and ‘waiting’) and social behaviours (such as ‘play’). The otters also spent significantly more time visible than ‘out of sight’ when there were no visitors present. This preliminary research provides information that may influence the way zoos and aquatic parks manage their otters, and contributes to the improvement of the welfare of animals in human care

    Synthesising bushmeat research effort in West and Central Africa: A new regional database

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    Unsustainable hunting threatens both biodiversity and local livelihoods. Despite high levels of research effort focused on understanding the dynamics of bushmeat trade and consumption, current research is largely site specific. Without synthesis and quantitative analysis of available case studies, the national and regional characteristics of bushmeat trade and consumption remain largely speculative, impeding efforts to inform national and regional policy on bushmeat trade. Here we describe the structure and content of the West and Central African bushmeat database which holds quantitative data on bushmeat sales, consumption and offtake for 177 species from 275 sites across 11 countries in two regions, spanning three decades of research. Despite this wealth of available data, we found important biases in research effort. The majority of studies in West and Central Africa have collected market data, which although providing a useful record of bushmeat sales, are limited in their ability to track changes in hunting offtake. In addition, few data exist for West Africa, and few studies have tracked changes over time, using repeat sampling. With new initiatives in the regions to track bushmeat hunting, this database represents an opportunity to synthesise current and future data on bushmeat hunting, consumption and trade in West and Central Africa, identify gaps in current understanding, and systematically target future monitoring efforts

    How long is a piece of Strix? Methods in measuring and measuring the measurers

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    An experiment to quantify intra- and interobserver error in anatomical measurements found that interobserver measurements can vary by over 14% of mean specimen length; disparity in measurement increases logarithmically with the number of contributors; instructions did not reduce variation or measurement disparity; scale of the specimen influenced the precision of measurement (relative error increasing with specimen size); different methods of taking a measurement yielded different results, although they did not differ in terms of precision, and topographical complexity of the elements being considered may potentially influence error (error increasing with complexity). These results highlight concerns about introduction of noise and potential bias that should be taken into account when compiling composite datasets and meta-analyses
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