BEEtag: A Low-Cost, Image-Based Tracking System for the Study of Animal Behavior and Locomotion Crall, James D. ; Gravish, Nick ; Mountcastle, Andrew M. ; Combes, Stacey A. Abstract Publication: PLoS ONE Pub Date: September 2015 DOI: 10.1371/journal.pone.0136487 Bibcode: 2015PLoSO..1036487C