title: The private life of echidnas: using accelerometry and GPS to examine field biomechanics and assess the ecological impact of a widespread, semi-fossorial monotreme.
abstract: The short-beaked echidna (Tachyglossus aculeatus) is a monotreme and therefore provides a unique combination of phylogenetic history, morphological differentiation and ecological specialisation for a mammal. The echidna has a unique appendicular skeleton, a highly specialised myrmecophagous lifestyle and a mode of locomotion that is neither typically mammalian nor reptilian, but has aspects of both lineages. We therefore were interested in the interactions of locomotor biomechanics, ecology and movements for wild, free-living short-beaked echidnas. To assess locomotion in its complex natural environment, we attached both GPS and accelerometer loggers to the back of echidnas in both spring and summer. We found that the locomotor biomechanics of echidnas is unique, with lower stride length and stride frequency than reported for similar-sized mammals. Speed modulation is primarily accomplished through changes in stride frequency, with a mean of 1.39 Hz and a maximum of 2.31 Hz. Daily activity period was linked to ambient air temperature, which restricted daytime activity during the hotter summer months. Echidnas had longer activity periods and longer digging bouts in spring compared with summer. In summer, echidnas had higher walking speeds than in spring, perhaps because of the shorter time suitable for activity. Echidnas spent, on average, 12% of their time digging, which indicates their potential to excavate up to 204 m3of soil a year. This information highlights the important contribution towards ecosystem health, via bioturbation, of this widespread Australian monotreme.
authors: School of Science and Engineering, University of the Sunshine Coast, Sippy Downs, QLD 4556, Australia cclement@usc.edu.au.|School of Biological Sciences, University of Queensland, St. Lucia, QLD 4072, Australia.
authors: Christofer J
authors: 0000-0001-8174-3890
authors: CJ
authors: Clemente
authors: Department of Environment and Agriculture, Curtin University, Perth, WA 6102, Australia.|Zoology, School of Animal Biology M092, University of Western Australia, Perth, WA 6009, Australia.
authors: Christine E
authors: CE
authors: Cooper
authors: Department of Environment and Agriculture, Curtin University, Perth, WA 6102, Australia.|Zoology, School of Animal Biology M092, University of Western Australia, Perth, WA 6009, Australia.
authors: Philip C
authors: PC
authors: Withers
authors: School of Information Technology and Electrical Engineering, University of Queensland, St. Lucia, QLD 4072, Australia.
authors: Craig
authors: C
authors: Freakley
authors: School of Information Technology and Electrical Engineering, University of Queensland, St. Lucia, QLD 4072, Australia.
authors: Surya
authors: S
authors: Singh
authors: School of Information Technology and Electrical Engineering, University of Queensland, St. Lucia, QLD 4072, Australia.
authors: Philip
authors: P
authors: Terrill
mesh_terms: D061725:Accelerometry; D000818:Animals; D001696:Biomechanical Phenomena; D001835:Body Weight; D017753:Ecosystem; D040362:Geographic Information Systems; D012621:Seasons; D013045:Species Specificity; D004442:Tachyglossidae / Q000502:physiology*; D016138:Walking / Q000502:physiology
keywords: Digging; GPS; Locomotion; Stride; Tachyglossus aculeatus