Francelle, I too thought it was a vole. But looked that up and it didn't look anything like a vole on the internet. So my husband wrote these people and this is the answer:
You are correct it is a shrew. If you tell me where it was photgraphed I
>could try and guess the species. If it was in the desert habitat types
>(below 4000 foot elevation) it is a desert shrew.
>Bill Van Pelt
>Nongame Birds and Mammals Program Manager
>2221 West Greenway Road
>Phoenix, AZ 85023
>Phone 602-789-3573, Fax 602-789-3926
Since we are at about 3500 feet I guess it is a desert shrew. I realized the last batch of mulch I got from my supplier was at the bottom of the pile, as they were almost out--so I'm thinking I might have got them in that batch of mulch.