My niece and I have chick brooders set up in a large shed. I have a large metal livestock water trough. She has a huge dog crate (Great Dane sized) with one huge plastic tub with older Showgirls. She also had 10 Showgirls and Silkies around three weeks old. They were inside a large plastic tub with heat plate sitting beside her others. The lid was locked on. It has a wire cutout lid. Only this tub was not inside her crate. Today around lunchtime some predator killed all 10 babies. The animal left wings, feet, and one hollow backside with legs. All pieces were left sitting in front of the metal crate’s door. No other chicks were touched. Any ideas what it was and how to keep the others safe.