To Mike Davis, there's something different about a summer sled dog.
Davis, a professor and the endowed chair of the Department of Physiological Sciences at Oklahoma State University, is one of the preeminent sled dog researchers in the country. For the last few summers, he's spent time at kennels across Alaska, researching how sled dogs function. This summer, he been at the Happy Trails Kennel of four-time Iditarod champion Martin Buser. He took muscle samples from Buser's racing squad, stripping the cells down to their basic elements to get a better sense of how they produce the energy that allows them to race extraordinarily long distances day after day.
It's a scientific way of learning how sled dogs work, though Davis is keenly aware of how the animals function on a personal level.
When Davis sees the dogs at the end of March, essentially the end of the racing season, they look lean, like the high-level athletes they are, with personalities matching their dedication. After a season during which they run thousands of miles in challenging conditions, the dogs are poised and confident.
But by early September, the temperatures have cooled and mushers are tiptoeing into their first runs of the season. Already, Davis said, you can see the marked change in the dogs.
"They're just a bunch of nuts," he said.
Those nuts are the sled dogs of summer, a group of Alaska canines with responsibilities as varied as their fur color.
Racers spend their summers hanging out in the dog yard in preparation for the coming season, either lounging on or in their houses or going for short runs to stretch their legs.
Working dogs earn their keep driving tourists on short runs along wooded trails or on top of pristine glaciers. It's big business for mushers in Alaska, with at least a half-dozen tour operations across the state.
For Raymie Redington, the 69-year-old son of Joe "Father of the Iditarod" Redington, summer is about keeping visitors happy. This is his 20th season of entertaining visitors at Iditarod headquarters just outside Wasilla. The dogs take visitors on a short run among the wooded trees near Wasilla's Lake Lucille. It's nice and shady, according to Redington, and perfect for visitors looking for a true Iditarod experience with racing dogs.
Redington hasn't run the race since 2001, but he leases dogs to other mushers, including top contenders like Nicolas Petit of Girdwood, who placed sixth in 2013 and was a 2014 race leader until he unexpectedly withdrew outside of Unalakleet.
Redington said that while the dogs (and puppies) are legitimate racing dogs, they also know that the summer tour business is serious, too. Redington said that when the animals see the buses line up, full of tourists, the dogs know it's time to go to work.
"They ain't laying around much," Redington said. "They been there so much, they know everything. They see a bus pull up, they know they're going to go to work."
But it's fun work for the dogs, he said. They get to interact with all kinds of people from all over the world -- from 5-day-old babies to 95-year-old grandmothers.
For Dallas Seavey, the 2014 Iditarod champion, summertime means finding the balance between tourism and racing.
This summer, some of his dogs went to Seward to work for his dad, Mitch, who operates the Seaveys' Ididaride tour operation. But Seavey's younger dogs -- the ones who led him to his second record-setting victory in 2014 -- stayed back at his Willow kennel.
What those racers do with their time varies day to day. If it's approaching 80 degrees, they want nothing more than to hang out on their doghouses or maybe run in a sprinkler that Seavey sets up in the yard. If it's cooler, he takes the dogs out running at a nearby swamp. A few rambunctious ones might jump into the lake, but most stay close to the shore, cooling down by plopping down in soggy bits of marsh.
But even during the summer, when relaxation is the priority, the slightest glimpse of a harness starts all the dogs yapping in anticipation of a run, even if it's 80 degrees.
And now that the Alaska State Fair has passed and temperatures are dropping for good, it's time get back to training.
"It's like they just flipped a switch and they're ready to go."