I was surprised that they weren’t attacked when I first planted them! I’m sure the voles will be after them this year!
There are many mole/vole controls , many of which have moderate success.
You can plant castor beans (natural occuring poison), moth balls (ole timey ones, only), chemical controls , but the best is a soil drench.
Yes , once they learn where the tasty blubs are located, they will scout the area where they were before - it's a learned behavior .
If you remove the bulbs and place them in a pot in the garage , cover the pot with fine metal screening located somewhere above the floor.
If left in the ground and covered with screening , the moles and voles simply dig under the screening, and munch away.