They clip the tails when lamb marking, don't they... I don't think I've ever seen an adult sheep with its tail other than pet sheep, and you can see why they would want to cut the tail, since the wool get all messy...
It’s honestly a little weird to see lambs with tails because they are typically docked so early after they are born. The tails are long and legit look like a 5th leg on some of them.