thats whats throwing me off! also i cant see them being caught on land as they sit right on the bank BUT at the same time im finding them on the footpath side which is hard to get out of and open when the other side is level with the water and all cover!!!
maybe the crows are killing them, getting disturbed and rats are getting them then???
only video i can find is this and at the end you can hear the kid say "its heads already fell off" so it does happen with crows!!!