Two squirrel boxes were removed from Dalhousie Estates, Brechin, on Sunday (April 30).
Police Scotland is appealing for information following the incident.
A Tayside Division spokesperson said: “It is believed that these may have been taken due to a lack of knowledge by the public as to their use.
“These boxes are being used in a national operation as a legal way to assist in the control of the grey squirrel population in the area.
“The boxes are provided via a grant from the Scottish Government’s Rural Development Contracts in conjunction with the Scottish Wildlife Trust and are used to trap grey squirrels due to them carrying a disease known as squirrel pox which is harmless to grey squirrels but potentially fatal if contracted by red squirrels.
“This is a legal and legitimate way of controlling the squirrel population in the area and these boxes should not be tampered with.
“If you have any information as to the whereabouts of the boxes, please call police on 101 quoting crime reference number 11027/17.”