A case study on small rodent usage of exterior rodent bait stations in a suburban backyard

Exterior rodent bait stations are used for outdoor rodent control with rodenticides worldwide. Rodenticides are considered crucial for reliable protection of stored food products. However, factors associated with bait station visitation, especially for non-commensal rodents, are not well understood. Seven exterior rodenticide bait stations of three different designs, including three EZ-Secured®, two Rodent Cafe® and two Evo® Express™ models were used with non-toxic bait to examine small rodent activity through bait mass reduction and fecal pellet counts in a single suburban yard (n = 1) over a single winter season. These stations were set at seven locations within the yard to mimic typical exterior rodent management practices in Ontario, Canada, and rotated clockwise between these locations biweekly. Due to uneven block sizes and the non-random design for data collection, no statistical analyses were performed. Stations placed at the foundation of the home or in the center of the mowed lawn showed no fecal deposits or bait mass reduction. Rodents continued to visit stations during weeks when bait was removed from them, and fecal pellet counts were visually related to weekly bait mass reduction. Lower temperatures also corresponded visually with greater bait mass reduction. • Bait stations placed against the home foundation or in the lawn had no fecal deposits or bait mass reduction. • Bait mass reduction appeared to increase visually with lower minimum ambient temperature. • Fresh fecal pellet counts increased visually with bait mass reduction. • Fresh fecal pellets, some with DETEX® residue, were found in stations in weeks when no bait was present.