House wrens are very territorial & will invade boxes & destroy eggs &
babies. Maybe that is the culprit.
Barbara Powers

>From: Lee Allaben - Century21 Advantage <[log in to unmask]>
>Reply-To: Vermont Birds <[log in to unmask]>
>To: [log in to unmask]
>Subject: [VTBIRD] eggs removed from nest
>Date: Wed, 1 Jun 2005 08:57:41 -0400
>
>I have been monitoring 17 nest boxes. Yesterday I checked one that had 6
>tree swallow eggs in it. I found all 6 eggs on the ground either broken or
>with a hole pecked in it. Other than the house sparrow is there any other
>bird that would do that?
>
>Lee
>  So. Burlington