See the National Park Service's newest canine rangers

"Every winter deep snow smothers the boreal forests and brushy tundra within Alaska's Denali National Park and Preserve. When it gets so cold that motor oil thickens and snow mobiles can't start, rangers turn to an age-old solution to get around: sled dogs. Sled dogs have been an essential part of daily operations at Denali for more than 100 years. The dogs provide rangers with a reliable way to etch trails, haul supplies and even assist park scientists with snow-dependent research."

"Rangers train a new litter for these tasks almost every year, adding to the team of more than 30 sled dogs serving the Denali area. The newest litter of sled dog puppies has just arrived, and you can follow their progress toward growing into full-fledged canine rangers via a live puppy cam. Born on March 30, the five puppies Sequoia, Mammoth, Rainier, Teton and Mesa are housed in the Denali kennel and were named after U.S. National Parks in honor of the 250th anniversary of the country's independence."

"The puppies have been growing by more than a pound per week since their birth and, at just six weeks old, they are already very vocal, full of personality and well on their way to honing the innate abilities that help make them excellent canine rangers. It's ingrained in this breed of dogs to want to want to pull, to run and to explore, says David Tomeo, the park's kennels manager. We have quite the training program for our dogs to help them build confidence [in those skills] as well."

"Arctic dogs have been evolving alongside humans for millennia. The earliest direct evidence of humans using dogs to pull sleds comes from 9,000-year-old remains of two dogs found in the Eastern Siberian Arctic. Genetic evidence suggests those"

Deep winter conditions in Denali National Park and Preserve can prevent vehicles from operating, so rangers rely on sled dogs to travel, create trails, and haul supplies. Sled dogs have supported daily operations for more than 100 years, and they also assist park scientists with snow-dependent research. Rangers train new litters nearly every year, maintaining a working team of more than 30 sled dogs in the Denali area. Five puppies—Sequoia, Mammoth, Rainier, Teton, and Mesa—arrived in the Denali kennel and were named for U.S. National Parks to honor the 250th anniversary of independence. The puppies are growing rapidly, are vocal and full of personality, and are developing the pulling, running, and exploring instincts needed for future canine ranger work.

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