When Arlo, a young pit bull mix, was brought to Marin Humane to find a new home, staff and volunteers were impressed by his affectionate nature and sense of fun. His health seemed good. His eyes were bright and intelligent, his handsome brindle-and-white coat was shiny, and he enjoyed romps in the shelter parks with volunteers. But he had a slight limp and it became more pronounced as the days went by. Marin Humane’s veterinarians performed an X-ray and found that happy Arlo was surely in a lot of pain. His right leg was so damaged that it could not be surgically repaired. His leg needed to be amputated to relieve this charming dog of his chronic discomfort.

Given the enormous overcrowding in animal shelters — and the challenges of re-homing pit bull mixes — Arlo was fortunate to find himself at a shelter where every animal is given a fair chance at starting a new life. In no time at all, Arlo had surgery, recovered, and was ready for adoption. Today, Arlo the tripod pittie is the same happy-go-lucky guy, perhaps even more so now that the pain has gone.

Arlo is one of three tripods at Marin Humane waiting for new families. Sweet little Dexter, a Chihuahua mix, had his left front leg removed in our clinic when it too was beyond repair. Dexter’s agility and zest for life is astonishing. He dashes around like any other lively little dog and tosses toys in the air. In the interests of full disclosure: he has a reputation for annoying cats. Well, no dog is perfect — not even Dexter.

Then there is Pi, a young border collie mix, who has earned himself a special place in the hearts of many. Pi was found in San Rafael and brought to the shelter with half his rear right leg missing. It was extremely difficult for this gentle dog to get around without stumbling. Watching Pi struggle to keep his balance and move about with his half leg while retaining his sweet nature and desire to please was heart-rending for everyone. Pi, too, was booked into the operating room. His maimed leg was properly removed and Pi is quickly getting used to having three legs instead of four.

Does having one less leg mean they can’t be like “regular” dogs? “Tripod animals can do just about anything any four-legged animal can do,” says Dawn Kovell, Marin Humane’s director of behavior and training. “Not only can they swim and play fetch, but they can compete in canine sports like agility and flyball. Jagger, a three-legged dog, earned a spot in the Flyball Hall of Fame and tripod Serena earned a specialist championship in canine performance events agility. Of course, they can also be champion snugglers, pizzas thieves and therapy dogs, too. These are individuals with their own preferences, skills and quirks. In other words, just like all dogs.”

It’s amazing how quickly tripods learn to cope. Self-pity does not exist in the animal world. Muscle activity changes as they adjust to their new reality, and soon they’re doing just fine.

Sometimes people assume animals with missing limbs or other disabilities must be sad. Fortunately, animals are incredibly adaptive and usually find a joie de vivre no matter what. Just ask the tripods Arlo, Dexter and Pi.

To learn more about these dogs and others awaiting their forever home, go to marinhumane.org/adopt.

Neil Lurssen is a retired journalist and volunteer at Marin Humane which contributes Tails of Marin articles and welcomes animal-related questions and stories about the people and animals in our community. Go to marinhumane.org, Twitter.com/marinhumane, or email lbloch@marinhumane.org.