Sequoia - shrews may be related to mice, but they are not likely eating your plants. Shrews have very high metabolic rates, therefore voracious appetites, and eat as much as twice their body weight daily. Their high metabolic rate necessitates that their diet is nutrient rich, so they mostly eat insects, worms, small animals, etc. Nuts and seeds are the main plant components of their diet, not foliage. A shrew placed in a cage with several mice will be alone with a skeleton collection within a couple of days and quickly perish once the mice have been devoured. Shrews help control mice and voles rather than being a threat to your plants.
Edit: I went to verify what I had written above and found I misspoke; our local species of shrew can eat up to 3 times its weight daily, and voles are a preferential component of its diet. For more info see
https://en.wikipedia.org/wiki/...
