POLICE say a duck was found decapitated at Kennington Reservoir on Wednesday night.
It is unclear what happened to the duck but police suspect it may have been the target of animal cruelty.
They want to speak with two boys believed aged roughly 12- to 14-years-old seen riding in the area at about 6pm, who may be able to help with the investigation.
The boys are thought to have been near to the reservoir on mountain bikes fitted with all-terrain fat bike tyres, Acting Sergeant Rod McDowell said.
He hoped others who may have seen or heard something would also come forward.
"Anyone with information should contact Crime Stoppers or get in touch with Constable Blair Crandell at the Bendigo police station," Acting Sergeant McDowell said.
Crime Stoppers can be contacted on 1800 333 000 and reports can also be made at crimestoppers.com.au