Development of a multi-sensor biologging collar and analytical techniques to describe high-resolution spatial behavior in free ranging terrestrial mammals

Abstract

Abstract 1. Biologging has proven to be a powerful approach to investigate diverse questions related to movement ecology across a range of spatiotemporal scales and increasingly relies on multidisciplinary expertise. Advancements in sensor design and analytical techniques continue to push the boundaries of this emerging discipline. However, the growing variety of animal-borne equipment, coupled with little consensus regarding analytical approaches to interpret complex datasets presents challenges and makes comparison between studies and study species difficult. 2. Here, we present a combined hardware and analytical approach for standardizing the collection, analysis and interpretation of multi-sensor biologging data. We develop (i) a custom-designed integrated multi-sensor collar (IMSC), which was field tested on 71 free-ranging wild boar (Sus scrofa) over 2 years; (ii) a machine learning behavioral classifier capable of identifying six behaviors in free-roaming boar, validated across individuals equipped with differing collar designs; and (iii) laboratory and field-based calibration and accuracy assessments of animal heading measurements derived from raw magnetometer data. 3. The durability and capacity of IMSCs exceeded expectations, with a 94% collar recovery rate and a 75% cumulative data recording success rate across all collars deployed, with a maximum data logging duration of 421 days. The behavioral classifier had an overall accuracy of 85% in identifying the six behavioral classes across all collar designs and improved to 90% when tested on data from the IMSC only. Both laboratory and field tests of magnetic compass headings were in precise agreement with expectations, with overall median magnetic headings deviating from ground truth observations by 1.7° and 0°, respectively. 4. Here we present the development of the IMSC coupled with an analytical framework verified by ground truth data for identifying core behaviors and spatial orientation in free roaming boar. We highlight the potential of additional analyses available using this commercially produced system that can be adapted for use in future studies on terrestrial mammals.