Two kelpies from Tasmania are among a dozen from around the country vying for the title of the nation's hardest-working dog.
Lady from Epping Forrest and Monty from Paradise are joining the others in the Cobber Challenge; they've been fitted with GPS collars to see how much ground they cover on their respective farms.
Ridley's Ian Moore says they'll be tracked over three weeks.
"They are often the unsung heroes of hardworking farms, and we're celebrating the very special relationships which exist between working dogs and their owners, which really captures Australian mateship," he said.
"Last year's winner, Boof [of Victoria], ran a staggering 631 kilometres over the three weeks, averaging about 10.6 kilometres per hour.
"If you put that in human terms, that's like running a marathan-and-a-half at 10.6 kilometres an hour, which is just elite athlete level."
Top, middle: Lady from Epping Forest with owner Brendon Johnson. Bottom: Jack Febey and Monty, of Paradise (supplied).