The life-span of Trowbridge's shrews is around 1.5 years. They do not hibernate, but remain active year-round. They are roughly twice as abundant in the fall as in the spring. Insects are a primary food source for the shrews, but they also will eat spiders, worms, and centipedes. After identifying food items in the Trowbridges Shrew’s stomach, the most consumed items were centipedes (Chilopoda), spiders (Araneae), internal organs of invertebrates, slugs and snails (gastropoda) and unidentified invertebrate material. During the reproductive season, food consumption is greatest. They also eat plants. Compared to other shrews in the genus "Sorex", Trowbridge's shrews eat more vegetable matter. During winter months, they may feed on conifer seeds, such as Douglas-fir and pine, as well as other plant seeds.