Geese have been killed or died because of their injuries after being shot on Birch Vale Reservoir.
Derbyshire Constabulary Wildlife Officers have had reports of incidents over the last few days.
A number of the geese are still on the lake with injuries. These will be caught by the RSPCA (England & Wales) and taken for treatment.
The RSPCA have already taken a number of injured geese from the lake, some of which have had to be euthanized due to injury.
It has been reported that someone is shooting these Geese with a High Powered Air Rifle.
These Geese are suffering with injuries.
Derbyshire Constabulary Wildlife Officer said: "We are working together with the RSPCA on this incident and need the public’s help again."
If anyone knows or is aware of who might be doing this please call 101 and quote incident 1064-210419 or call Crimestoppers on 0800 555 111.