Repellent effect of synanthropic house mouse urine odor on small forest mammals

In this study, we examined the effect of synanthropic house mouse (Mus musculus) urine odor on catching probability of small mammals to live traps. We conducted a series of field experiments in August 2016 and 2017 in a natural forests of the northwestern Moscow Region (Russia). Small mammals were trapped at two 4-ha fields using capture-mark-recapture technique by setting 200 live traps (100 points, 2 traps per point) within each field. One trap in each pair was odorless (control) with bait only, whereas the other one was odor-baited with 20 μL of the urine of a synanthropic house mouse. Further analysis was based on the data collected from 2 rodent species (bank vole Myodes glareolus, herb field mouse Apodemus uralensis) and 3 shrew species (common shrew Sorex araneus, Laxmann's shrew Sorex caecutiens, and Eurasian pygmy shrew Sorex minutus). As a result, only bank voles significantly avoided odor-baited live traps. Using generalized linear mixed models, we showed that the choice of a trap by bank voles depended on their age, whereas the probability of repeated capture to a certain live trap was related to their prior experience. We discuss the possible role of components of synanthropic house mouse urine in the population management of exoanthropic small mammals.