Dog owners in South Holland, Bourne and the Deepings are being warned to keep their pets safe by a leading rural lobbying group.
More than 200 dogs were stolen across eastern England last year, including 24 from Lincolnshire, prompting fears by the Country Land and Business Association (CLA) that dog thefts are on the increase.
The warning from CLA eastern regional director Nicola Currie is backed up by figures from More Than pet insurance group which showed that since 2012, cats and dogs worth more than £670,000 have been stolen.
Mrs Currie said: “Many dogs are targeted by thieves because they can make money selling them on, often for breeding or fighting.
“By leaving a much-loved animal in your garden, in sight of a road or a public right of way, it gives thieves a golden opportunity to take your animal.”
The UK’s first ever Pet Theft Census by More Than showed the most stolen dog breeds were Staffordshire Bull Terriers and labradors.