Woodmice (Apodemus sylvaticus) can distinguish conspecific from heterospecific odors in the field.

In order to eliminate a common source of bias from trap-choice experiments in the field, trapping data from a study on the olfactory biology of the woodmouse were screened, and only those in which a direct choice existed were analyzed further. Woodmice choose conspecific odor to no odor but make no distinction between heterospecific odor and no odor. When choosing between conspecific and heterospecific odors, a significant majority choose conspecific.