They come in all colours and temperaments and only the skill of their two-legged handlers can distinguish the top working dogs from barking also-rans.
But for the first time in its 70-year history, this year's National Sheep Dog Trial at Hall with 230 entries, does not have a kelpie entered.
Gold Creek Station's Craig Starr, who provides the sheep for the week-long trial, uses his kelpie, Digger, to round up the stock, but concedes the 2½-year-old workaholic would be disqualified for getting between him and the merino ewes.
''Go way back. Get over, get over,'' he calls, sending Digger over the backs of a freshly penned mob.
Greg Prince, who has won the national trial 14 times, more than twice as many as his nearest rivals, has never won with a kelpie. Mr Prince has won elsewhere with kelpies, but reckons border collies are more suited to Hall's arena-style competition.
The trial's secretary, Charlie Cover, of Yass, believes kelpies have captured Australians' imagination.
''Not only that, but to a big degree the imagination and interest of the graziers,'' Mr Cover said.
''Without getting too deep and meaningful about it, it is because they are a very boisterous dog, which looks to be doing a lot of work. They look as though they are getting the job done.''
Mr Cover said it was unusual not to have at least 5 to 10 per cent of entries taken up by kelpies in the trial, which this year will be held from next Tuesday to Sunday.
Mr Prince and Mr Cover said kelpies were bred for working in confined spaces, where they can load a stock truck full of sheep quickly, and run over sheep's backs and push them through yards. Mr Prince said the collies and kelpies were bred for different reasons. ''The kelpie is more for mob-type work, station and yard work; the collie is more of a paddock-type dog. There are some real good kelpies that can handle sheep dog trialling, too,'' he says.
Mr Prince breeds his own dogs and is always on the lookout for the ''X factor'' - a dog that can quieten down and control stock. ''It is something you can't train into a dog. It has got to be bred there. Without that factor you are struggling all the time,'' he said.
People are paying from $1500 to $10,000 for good working dogs these days, he said. Mr Prince, who is from Dubbo and with his wife Jan teaches jackaroos and jillaroos dog handling skills, said large numbers of wild goats had driven up demand.
''We get phone calls, we might get two or three a week looking for trained dogs to round up these feral goats. They are all over NSW. Once you get out west of Dubbo, towards Bourke, Brewarrina and Cobar, they are everywhere.
''They can get good money for goats now and they can pay for a dog in a week. It doesn't take them long.''