1 Tahrcountry Musings: Estimating body mass of pumas

Friday, May 06, 2011

Estimating body mass of pumas

Estimating body mass of pumas (Puma concolor)
Brian D. Jansen and Jonathan A. Jenks 
Wildlife Research 38(2) 147-151, Published: 20 April 2011

Even though this paper is about estimating body mass of pumas, the facts enumerated here might come in handy for other researchers also
Here Brian D. Jansen and Jonathan A. Jenks from the Department of Wildlife and Fisheries Sciences, South Dakota State University have attempted to estimate body mass of Pumas from their size.
 In remote and rugged terrain transporting equipment needed to weigh a captured animal is not often a feasible proposition. Here the option is to go in for a workable formula. Formulas have been developed for some species of large ungulates and carnivores. No work has so far been done on Pumas till the researchers here attempted it.
The researchers 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). 
Multiple regressions were used to determine the relationships between body measurements and body mass for 58 pumas in the Black Hills. The researchers then applied the equation to eight pumas that they captured in areas outside the Black Hills study population.
It was 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. The 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 the model was –6.3–6.3 kg. The researchers found the difference between predicted and actual body mass of pumas from other populations was –0.40 kg ± 1.45 (s.e.). The relationship between body measurements and body mass was similar, despite the differences in location and environments

No comments: