Body size and extinction risk in Brazilian carnivores

Abstract

Body size and extinction risk in Brazilian carnivores. Biota Neotrop., 9(2): http://www.biotaneotropica.org.br/v9n2/en/ abstract?article+bn00509022009.Abstract: Because extinctions are not random across taxa, it is important for conservation biologists to identify the traits that make some species more vulnerable. Factors associated with vulnerability include small geographical ranges, low densities, high trophic level, "slow" life histories, body size, and tolerance to altered habitats. In this study we examined the relationship of body size, reproductive output, longevity, and extinction risk for carnivores occurring in Brazil. We used generalized linear models analyses on phylogenetically independent contrasts to test the effect of body size alone, and the combined effect of body size, litter size and longevity on extinction risk. Body size appeared in the two best models according to the selection criteria (AIC), and it was the most plausible bionomic variable associated with extinction risk. Litter size and longevity, bionomic traits previously associated with threat risk of Brazilian carnivores, were implausible. The higher extinction risk for larger species could result from body size influencing vulnerability to different human activities, such as killing, habitat destruction and fragmentation, and the small size of natural reserves. Keywords: carnivores, independent contrasts, longevity, reproductive output, South America, vulnerability to extinction.FORERO-MEDINA, G., VIEIRA, M.V., GRELLE, C.E.V. & ALMEIDA, P.J. Tamaño corporal como factor de amenaza en carnívoros brasileros. Biota Neotrop., 9(2): http://www.biotaneotropica.org.br/v9n2/es/ abstract?article+bn00509022009.Resumen: Debido a que las extinciones no son aleatorias a través de los diferentes taxa, es importante para los biólogos de la conservación identificar las características que hacen a algunas especies más vulnerables. Los factores asociados con la vulnerabilidad incluyen distribuciones geográficas pequeñas, densidades poblacionales bajas, niveles tróficos altos, historias de vida "lentas", tamaño del cuerpo, y tolerancia a habitats alterados. En este estudio examinamos la relación del tamaño corporal, el potencial reproductivo y la longevidad con el riesgo de extinción para los carnívoros brasileros. Realizamos análisis de modelos lineares generalizados con contrastes filogenéticamente independientes para probar el efecto del tamaño corporal solo, y el efecto combinado del tamaño corporal, el tamaño de la camada y la longevidad sobre el riesgo de extinción. El tamaño del cuerpo apareció en los dos mejores modelos de acuerdo con el criterio de selección (AIC) y es la variable bionómica más plausible afectando el riesgo de extinción. El tamaño de la prole y longevidad, otras variables bionómicas que han presentado tal efecto en otros estudios, fueron implausibles. La mayor probabilidad de amenaza para las especies grandes puede deberse a que el tamaño del cuerpo afecta la vulnerabilidad a diferentes actividades humanas como la caza, la de...

Habitat loss and mammalian extinction patterns: are the reserves in the Quadrilátero Ferrífero, southeastern Brazil, effective in conserving mammals?

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The Roles of Taxonomy and Systematics in Bat Conservation

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Medium- and large-sized mammals in forest remnants of the southern Cerrado: diversity and ecology

“…There are about 6,399 mammal species, 701 of which are distributed in Brazil and of which 194 can be considered medium-and large-sized (Paglia et al 2012;Burgin et al 2018). Due to recurring threats to the remaining populations, most mammal species, especially those of medium and large size, are under risk of extinction in Brazil (e.g., Grelle et al 2006). Previous empirical works have demonstrated that mediumand large-sized mammals are specifically sensitive to the effects of fragmentation (Chiarello, 1999;Calaça et al 2010;Magioli et al 2016) and changes in the landscape configuration (Garmendia et al 2013).…”

“…Previous empirical works have demonstrated that mediumand large-sized mammals are specifically sensitive to the effects of fragmentation (Chiarello, 1999;Calaça et al 2010;Magioli et al 2016) and changes in the landscape configuration (Garmendia et al 2013). Such threats affect medium and large sized mammals primarily due to the characteristics of this group, such as low population density (Grelle et al 1999), small litter size and long gestation period (Brown 1995), and body size (Forero-Medina et al 2009). In addition, behavioral characteristics such as activity patterns can be influenced by fragmentation processes (Norris et al 2010).…”