Everyone mistakes them for yorkies, until they get closer. They're aussie terriers, much heavier boned with a good terrier double coat, 15-18 pounds, a bit more for males. They keep vermin off the property, the two on the right cornered a 'possum about 6 weeks ago, the guy on the left is my son's pup, 6 months old, was inches from a rabbit earlier in the week. The middle two ran off the neighbor's cat a couple of years back, the cat sticks to easier pickings, like the lab down the street.
They see weather like this; http
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And hang out for hours doing this; http
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That's a full size coal shovel behind the one guy. I had to dig snow away from the fence so they wouldn't jump over. Thankfully they listen well, as long as I was out there. The fence was almost a walk over.
If it weren't for a zillion fish & tanks, club & online fish related activities, I'd be doing a lot more with dogs.