Evaluating novel attachment methods for tracking devices on terrestrial mammals

Advances in consumer electronics and the increasing availability of spatially explicit data are driving a revolution in tracking animal movement. Free‐ranging avian, terrestrial, and marine species are now tracked at fine spatial and temporal resolutions, revealing useful insights into their ecology. However, miniaturized tracking devices are rarely attached to medium and large terrestrial mammals, with researchers deploying collars on most larger species. We deployed 6 prototype solar‐powered, global navigation satellite system (GNSS) tracking devices on 2 endangered large terrestrial mammals—scimitar‐horned oryx ( Oryx dammah ) and Przewalski's horse ( Equus ferus przewalski )—with devices attached to horns and tails, respectively. We assessed device performance as well as potential physiological and behavioral effects of these alternative attachments of tracking devices. Novel attachment methods achieved fix success rates of 31–100% (mean = 77%) and spatial accuracy (11–36 m) that compare well with standard collar attachments used on large terrestrial mammals (fix success: 29–100%, mean = 69%; spatial accuracy: 10–40 m). In generalized additive models, the presence of a device did not significantly predict behavioral or physiological stress for either species. Solar panels were able to maintain charge throughout the test period. However, deployment lifespan (mean = 55 days for horses and 26 days for oryx) was ultimately limited by attachment method. While a later modification substantially improved deployment length, attachment durability remains a key area for improvement. We urge ecologists and conservation practitioners to consider the full range of tracking devices and attachment methods available from tracking technology manufacturers, assess whether alternative attachments could achieve scientific or conservation objectives with reduced impacts on study species, and carefully test any tracking device before long‐term deployment.