Between noon on Sunday and Monday morning, a red Honda TRX500 worth £4000 was taken from a farm shed in the Waterbeck area.
And overnight from Monday to Tuesday a military green 350cc 2009 ‘Grizzly’ quad bike, pictured above, was stolen from a farm near Gretna.
Detective Constable Michael Scott said: “In recent weeks we have seen an increase in quad thefts in the Canonbie/Langholm/Lockerbie areas and I want to hear from anyone who may have seen any suspicious vehicles approaching farms or people who appear to be up to no good.
“I would encourage farmers and landowners to report all incidences of rural crime.”
The thefts come just a week after two trailers were taken from a yard near Eaglesfield – with a total value of over £10,000.
In all cases large vehicles would be needed to transport the stolen goods away.
Police are appealing for witnesses to all the rural thefts, and encourage anything suspicious to be reported at the time.
The Police Scotland spokesman said: “If anyone recalls seeing or hearing any suspicious activity, particularly around farms and rural areas where plant is located, I would ask them to get in touch with Police Scotland on the 101 phone number.”
Police have also offered safety advice, such as storing machinery and vehicles securely and without the keys.
Further advice can be obtained by contacting local officers.