Officers have appealed for residents to be vigilant after a number of wildfoul have disappeared in Matlock.
A statement by Derbyshire's Rural Crime Team said: " We have been made aware of a significant lack of Wildfowl of all species being present in the Matlock and Cromford area over the last week.
"They are non migratory and there is no explanation as to their disappearance.
"This information has come from the angling community who know the vicinity very well and are equally surprised as ourselves."
If you have any information, please call police on 101.