I have an 8 year old Australian Shepherd named Arwen (puppy picture is my avatar). If you know Aussies, 8 years old does not mean lazy dog. She is 100% energy. She is a wonderful dog with my pets, very gentle with my house rabbits, cat and my cockateil for 8 years (RIP). She even tries to mother wild baby birds in the yard - much to the real mother's unhappiness. Once she knows something is mommy's pet she feels it is her responsibility to protect it. I plan on getting chickens in the spring and am hoping on using her as a flock guardian when I have them out for supervised free range. I noticed an awesome trait she has. Last year we purchased 3 acres and put in an invisible fence. Since she now has so much open area to roam she has been watching the sky. She ignores most birds BUT if she sees a hawk or vulture she goes crazy. She will run along the ground under them and bark to drive them off. If my rabbits are out in their pens getting some green grass she will run to the pen and guard it by barking at the bird. I have been encouraging this behavior. She will be an excellent flock protector as my yard is very open and we have Red-shouldered, coopers and peregrine falcons that I see on a daily basis. She does not bark at the wild geese flying, crows or the blue heron - just the raptors. She has also run the red foxes in the area off our property twice. I don't let her tangle with the coyotes. Love my good dog.