we went in to do our nightly routine of feeding and changing the water. One our females mallards has been acting a little strange the last couple of days. She hung back from the crowd. she looked like her feathers were wetter than the other ducks( if thats possible) and she just had not been herself. We took her body out of the duck enclosure and buried her in the yard. We are new to the duck and chicken world and i was not sure what did this? We have six ducks in this enclosure. they were male/female pairs of peking( 1 set) and mallards ( 2 sets).thank you for your time and let me know what info anyone will need..