shorttail shrew

I love these tiny mammals - our shorttail shrews. They are 3 to 4 inches long and eat insects, worms, snails, etc. This is the first year I haven't noticed any. I thought this was because the yard has become so overgrown that I just don't see them, but then I remembered I used to hear them on occasion also - the twittering squeaks they make. Bill and I would see leaves or mulch moving and wait for a pointy, whiskered nose to poke out and sniff the air. So what happened to them? I can't blame neighborhood cats - I haven't seen them in our tangled yard recently either. Perhaps the next door neighbor who applied a lot of weed killer to his yard did them in. People and their priorities...