(Australia) A merle-coated Australian breed of working dog, originally bred for herding sheep.
Sulda, Dixie; Graham, Narelle (24 November 2022), “Fruit fly detection dogs find first larvae in the Riverland, stopping pest spreading to multiple orchards”, in ABC News, Australian Broadcasting Corporation: “Max the koolie and Rylee the German shepherd started work in October to detect Queensland fruit fly larvae and made their first find in a known outbreak area in recent days.”