Summary Scientific equipment, such as animal traps and autonomous data collection systems, is regularly left in the field unattended, making it an easy target for vandalism or theft. We tested the effectiveness of three label types, which differed in their information content and tone of the message, that is, personal, neutral or threatening, for reducing incidents of vandalism and theft of unattended scientific field equipment. The three label types were attached to 20 scientific equipment dummies each, which were placed semi-hidden and evenly distributed in four public parks in Munich, Germany. While the label type had no effect on the severity of the interactions with our equipment dummies, the personal label reduced the overall number of interactions by c. 40–60%, compared with the dummies showing the neutral or threatening label type. We suggest that researchers, in addition to securing their field equipment, label it with personal and polite messages that inform about the ongoing research and directly appeal to the public not to disturb the equipment. Further studies should extend these results to areas with different socio-economic structure.
