Estimating body mass of pumas (Puma concolor)
Context Body mass of animals has been estimated using body measurements and formulas have been developed for some species of large ungulates and carnivores. Pumas (Puma concolor) are often captured for sport and research in remote and rugged terrain and equipment needed to weigh a captured animal is not often carried because of the remoteness. Aims We investigated whether body measurements were related to body mass for pumas, to develop an equation that would accurately estimate body mass of pumas within desired tolerances (~10 kg). We also used our model to predict the body mass of pumas captured in other locales, to investigate the effectiveness of our model on other populations. Methods We used multiple regression to determine the relationships between body measurements and body mass for 58 pumas in the Black Hills. We then applied our top equation to eight pumas that we captured in areas outside the Black Hills study population. Key results We found that a model using body length (cm) and head and chest circumferences (cm) explained 89% of the variation in body mass; sex and age-class information did not contribute significantly to the model. Our top equation was as follows: body mass (kg) = –61.07 + 0.21 × body length (cm) + 0.56 × head circumference (cm) + 0.83 × chest circumference (cm). The 95% prediction interval for our top model was –6.3–6.3 kg. We found the difference between predicted and actual body mass of pumas from other populations was –0.40 kg ± 1.45 (s.e.). Conclusions We found the relationship between body measurements and body mass to be similar, despite the differences in location and environments. Implications This model could be used by researchers and sport hunters to estimate the mass of a pumas that were not weighed with a scale.