This is not merle colouration (a speckled effect that has associated health issues), but rather the result of the ticking gene. A number of breeds show ticking, which is the presence of colour through white areas, though the overall effect depends on other genes that will modify the size, shape and density of the ticking.In addition to the primary colouration, an Australian Cattle Dog displays some patches of solid or near-solid colour. Most Australian Cattle Dogs love the water and are excellent swimmers. By 1825, the Halls had established two cattle stations in the Upper Hunter Valley, and had begun a northward expansion into the Liverpool Plains, New England and Queensland. Getting his cattle to the Sydney markets presented a problem in that thousands of head of cattle had to be moved for thousands of kilometres along unfenced stock routes through sometimes rugged bush and mountain ranges.