My bean seedlings are getting eaten by something. The seeds pop up really nicely, then overnite, the tops get eaten. I initially thought it was racoons or some animal. I tested this by placing small plastic planters over the sprouts in the evening. In the morning though, the planters were undisturbed but the seedlings were still eaten.

Is this snails? slugs? bugs? gnomes?

Anything I can do? Is it better to plant seeds outside the planters in small pots then do a transfer?

For pictures:

http://thenotsogoodgardener.blogspot.com/