Quantifying the errors in animal contacts recorded by proximity loggers

Abstract

Automated contact detection by means of proximity loggers permits the measurement of encounters between individuals (animal-animal contacts) and the time spent by individuals in the proximity of a focal resource of interest (animal-fixed logger contacts). The ecological inference derived from contact detection is intrinsically associated with the distance at which the contact occurred. But no proximity loggers currently exist that record this distance and therefore all distance estimations are associated with error. Here we applied a probabilistic approach to model the relationship between contact detection and inter-logger distance, and quantify the associated error, on free-ranging animals in semi-controlled settings. The probability of recording a contact declined with the distance between loggers, and this decline was steeper for weaker radio transmission powers.

Conspecific Tolerance in a Solitary Small Carnivore, the Pacific Marten

“…Radio collars fitted with proximity loggers can reveal patterns of contact between individuals (Cross et al 2012, Wilmers et al 2015) by exchanging data during animal encounters including individual identification, temporal information (e.g., time, date, duration, frequency), and geographic location (Böhm et al 2009, Ralls et al 2013, Thiemer et al 2016). Logger settings can be adjusted to ensure that exchanges only occur when animals are within short contact distances (e.g., <1 m), greatly increasing the likelihood that individuals are interacting rather than being proximal by chance (Ossi et al 2022). Better documentation of rare and potentially complex behaviors can strengthen ecological inferences that can be made from encounters between individuals (Hertel et al 2020).…”