Paw preferences in the Asian small-clawed otter - using an inexpensive, video-based protocol to study laterality of rare species in the zoo.

It is still debated whether limb-use preferences represent a common trait in vertebrates, which is based on a shared phylogenetic history. Unravelling the evolutionary origin and pattern of paw preferences in vertebrates requires the analysis of a larger number of species within an ecologically relevant setting. We therefore investigated whether observations in a zoo enable the collection of reliable data sets by quantifying paw use in two independent groups of Asian small-clawed otters (Amblonyx cinerea). Employing a continuous focal animal sampling method, each day one of the ten individuals was video recorded from outside of the enclosure during usual activity. We selected four types of unimanual behaviour (reaching for food, reaching for non-food, reaching into a hole, carrying an object) and quantified paw use for each animal. Our study provides first evidences for individual paw preferences in otters, which were in line with previously reported forelimb use pattern in carnivoran species. Preferences differed between motor acts but for "reaching into a hole" a population-level right paw bias was detected. These data support that observations in a zoological setting are useful to explore task-dependent paw preferences and may facilitate future studies investigating paw preferences under experimentally controlled conditions.