Effects of a Stationary GPS Fix-Rate Bias on Habitat-Selection Analyses

Global Positioning System (GPS) radiotelemetry, as a data collection technique, currently suffers from largely unknown fix-rate biases that result in lost data due to environmental factors, which could lead to wrongful research conclusions. Estimates of bias within uncorrected data from free-ranging animals have not been reported. I tested the effects of a known fix-rate bias model on habitat-selection conclusions by correcting habitat-use data for mule deer (Odocoileus hemionus) and random data, and comparing outcomes to those of the original uncorrected data. In all cases, corrected and uncorrected data yielded similar habitat-selection conclusions. I attributed this to the model, which accounted for <10% data loss in all cases. Due to this small amount of explained data loss, I suggest that animal behavior (e.g., bedding vs. moving) is a large source of unexplained data loss from free-ranging animals and must be accounted for to best overcome biases in GPS radiotelemetry data.