Photos: Getting paid in sunsets at Voyageurs National Park

The Vermilion River from above.
1 The Vermilion River winds underneath the wing of Voyageurs National Park's floatplane just outside the park, near Crane Lake, in early August.

Not to be confused with the eponymous river that runs through Dakota and Scott counties, the Vermilion of northern Minnesota was a prominent trade route for voyageurs, French Canadian fur traders for which the park is named.
Houseboats on Lake Kabetogama.
2 Houseboats dock in a chain of islands on Kabetogama Lake in Voyageurs National Park on Aug. 7. The park's nearly 220,000 acres are almost roadless and its more than 270 campsites are accessible only by boat or floatplane, making rental houseboats one of the most popular means for visitors to explore the park. 
A beaver den from above.
3 Trails left by beavers branch out from a den nestled in marshland inside Voyageurs National Park. The park is home to many different species of mammals, birds and fish, making it a valuable resource for biologists and ecologists.

It's also vulnerable to invasive species, such as emerald ash borer and Eurasian watermilfoil, which has led the National Park Service to enforce strict rules on firewood and boats brought into the park. Watermilfoil is cause for extra concern, as it has been steadily moving northward across Minnesota, traveling on private boats and crowding out native plant species and disrupting ecosystems as it moves.

"We have a lot of invasives coming in, and if we can keep those at bay, it would be huge," Voyageurs facilities manager Bill Carlson said.
Boats drive on Namakan Lake.
4 A houseboat and a fishing boat cross paths on Namakan Lake inside Voyageurs National Park in early August. Voyageurs, in contrast to the to the adjacent Boundary Waters Canoe Area Wilderness, allows motorized boats on its waterways, which makes for a slightly noisier environment than exists in most national parks.

"What I've come to appreciate about Voyageurs is that it gives the beauty and the wildness of the Boundary Waters and makes it accessible to folks who wouldn't do a canoe, kayak or hiking trip,"said Mary Binger, who's been a ranger at Voyageurs for six years.
A heron roookery from above.
5 A grove of dead trees plays host to a heron rookery on the edge of a lake inside Voyageurs National Park. Park biologists have collaborated with pilots to monitor the park's heron, osprey and bald eagle populations for the last 45 years.

"Over those years I've monitored 338 eagles' nests," retired park biologist and volunteer Lee Grim said. "One nest in Namakan Lake has been used since 1974, and it still had young in it this year."
A boat passes through a channel in Voyageurs.
6 A lone motorboat cruises through island channels in Voyageurs National Park on Aug. 7. In the winter, many visitors trade their boats for snowmobiles, which are prohibited on Voyageurs' 900-plus islands, but are welcome on about about 104 miles of groomed trails that cut across the park's 30 lakes. 
Visitors tie up their boats and swim.
7 Visitors play and swim around three boats tied together in Kabetogama Lake in early August. Voyageurs National Park hosted 238,000 visitors from around the world in 2015, significantly fewer than the nearly 10 million who visited Great Smoky Mountains National Park in Tennessee, America's most-attended park. 
Kettle Falls Dam.
8 Water pours across the historic Kettle Falls Dam, which straddles the border between the United States and Canada. The dam and its accompanying hotel, built in 1910, have a colorful history: They've hosted trappers, fishermen, gold miners, loggers — and now tourists. 
Steve Mazur counts boats.
9 Ranger pilot Steve Mazur counts boats during a creel survey above Voyageurs National Park. Mazur is the park's sixth pilot. He arrived at Voyageurs six years ago, after working as a ranger in Death Valley National Park.

Park Service pilots' responsibilities are varied: They fly missions across Minnesota, Wisconsin and Michigan in collaboration with other agencies to assess storm damage; they monitor wildlife — and they patrol areas as law enforcement. But their primary role is in research.

"The driving force behind it has to be resource surveys," Mazur said. He's helped biologists monitor moose, wolves, eagles, cormorants and beavers from the cockpit of his plane.
The sunset on Namakan Lake.
10 The sunset reflects off the water and the tail of the park's floatplane in the middle of Namakan Lake. 
Steve Mazur stands on a plane float.
11 Ranger pilot Steve Mazur stands on one of his plane's floats after landing in the middle of Namakan Lake on Aug. 7. Park Service and private floatplanes are permitted to land on Voyageurs' four large lakes: Rainy, Kabetogama, Namakan and Sand Point. 
The sunset above Voyageurs.
12 The sun sets over Voyageurs National Park on Sunday, Aug. 7. "The saying back in the day was that we get paid in sunsets," ranger pilot Steve Mazur said. 
Ellsworth Rock Gardens from above.
13 Park visitors explore Ellsworth Rock Gardens on the shore of an island within Lake Kabetogama. The garden was built between 1944 and 1966 by Jack Ellsworth, a building contractor from Chicago who spent the summers on the island with his wife, Elsie. 
A statue stands in Ellsworth Rock Garden.
14 One of Jack Ellsworth's rock sculptures stands in the Ellsworth Rock Garden in Voyageurs National Park. The Ellsworths' residence on the island — along with many other cabins inside the park — were purchased by the National Park Service after President Richard Nixon signed the bill that created the park in 1971.

The purchases were a point of tension between locals whose cabins had been in their families for generations, but sentiments have slowly turned. "Water is the best resource, and clear air and so on is the best resource that this area has," retired park biologist and volunteer Lee Grim said, "and to make sure it stays that way in this part of the world is very important to this community."
Butch Eggen drives his boat.
15 Crane Lake, Minn., native and fishing guide Butch Eggen drives his boat across Sand Point Lake on Aug. 8. Eggen, who has been leading fishing expeditions for 43 years, believes that it is not the national park designation that makes Voyageurs special, but the conservation and preservation of resources for the future that comes along with it. 
Sun lit clouds over Sand Point Lake.
16 Low-hanging clouds above Sand Point Lake in Voyageurs National Park are lit by the setting sun on Aug. 8. 
Grassy Bay Cliffs at sunset.
17 The Grassy Bay Cliffs rise up out of Sand Point Lake in Voyageurs National Park. At 125 feet, the cliffs are one of the highest points in the park.
The granite here is just one piece of the park's rich geological history, which comes from its location on the southern tip of the Canadian Shield, a dome of volcanic bedrock that forms the heart of North America.
Sunset as seen from Nelson's Resort.
18 A man casts a line into Crane Lake from the dock of Nelson's Resort in early August.The most sought-after fish in Voyageurs is walleye, but the park is home to a wide variety of fish from lake to lake. 
The park's plane returns to the hangar.
19 The Voyageurs plane sits in its hangar at Falls International Airport in International Falls, Minn. The airport's Einarson Field hosts all manner of private, commercial and float planes, making it a hub of travel in an otherwise isolated area. 
The milky way above Voyageurs.
20 The Milky Way galaxy is visible from just outside Voyageurs National Park in Crane Lake on Aug. 8. The park's isolation allows for superb stargazing, giving visitors the opportunity to see shooting stars, planets and auroras on a clear night.