You must shut your birds in a predator proof coop each and every night in order to keep them safe from the night prowlers. Cover all coop openings with 1/2" hdw cloth. Know that chicken wire will keep your birds in, but will not keep predators out. You might want to look at electric fencing as an added layer of security. Weasels are notorious for going on binge killing sprees if they are able to access your flock. Being on a lake is going to make your flock very enticing to a great many different predators. They each have their own MO for killing.
