The geographic and demographic expansion of large herbivores in Europe leads to situations where many species live in sympatry: this is the case for red and roe deer in France. To monitor a given species, indirect methods based on signs like faeces, tracks or beds have been used for a long time. They are generally cheap and accurate. However, signs look similar between red and roe deer even though the former is larger than the latter. Our goal was to test if different bed characteristics (size, scraping) and adjacent signs (tracks, faeces, rubbing...) are sufficient to reliably distinguish between red and roe deer presence in the field. This practical question is part of a larger project on bed site selection by sympatric red and roe deer.