The Arctic National Wildlife Refuge has long been considered the "Last Great Wilderness" of the United States, and it's no surprise why. Located on nearly 19.3 million acres of tundra in the northeast corner of Alaska, this natural treasure is the largest and one of the most remote refuges in the U.S. It also happens to be one of the most threatened.

 

Thanks to the Wilderness Act of 1964, the refuge continues to thrive, but the onset of oil and gas exploration in the refuge's northern coastal plain, also known by petroleum companies as Area 1002, may soon change that. Only about 40 percent of the refuge is officially designated as a protected wilderness area. This area, known as the Mollie Beattie Wilderness Area, includes 8 million acres of arctic, subarctic and alpine ecosystems that are home to caribou, polar bears, moose, musk oxen and seals.

 

The map below offers a better understanding of how the petroleum industry is encroaching on the environment. The areas in red represent privately owned drill sites and the Trans-Alaska Pipeline System. Though the refuge's Area 1002 is small in contrast to the National Petroleum Reserve (the largest stretch of undisturbed public land in the U.S.), its coastal plain landscape happens to be the site of important calving grounds for the native Porcupine caribou herd.

 

To celebrate the 50th anniversary of the Wilderness Act and attempt to better understand the ecological and social importance of the region, Sierra Club Executive Director Michael Brune embarked on an eight-person summer rafting trip up the Aichilik River, which runs through the coastal plain and empties into the Arctic Ocean. In addition to Brune, the adventurous crew included Paul D. Miller, a composer, writer, musician who goes by the name DJ Spooky; and Rue Mapp, founder and CEO of Outdoor Afro, a network designed to re-reconnect African Americans to nature.

 

Continue below to see photos from their trip, with captions provided by one of the trip's leaders, Dan Ritzman of the Sierra Club's Our Wild America campaign.

 

Want to take action to strengthen the Arctic National Wildlife Refuge's protections? Consider signing this Sierra Club petition asking President Obama to designate the refuge's coastal plain region as a protected wilderness area alongside the Mollie Beattie Wilderness.

 

 

Dan Ritzman: Our inspiring week in the Arctic National Wildlife Refuge began with a view from above on a bumpy plane ride, but still the views could not be beat. President Eisenhower initially set aside the area for wildlife, wilderness, and recreation in 1960, and President Carter expanded the refuge to 19.6 million acres in 1980 for the American public and future generations to enjoy.

 

We had a great crew of eight make the journey through the Arctic Refuge. For some it was their first trip into America’s crown jewel of the north. For others the trip to the refuge is an annual ritual.

 

 

It did not take long before we pulled out our binoculars to spot wildlife. Sierra Club’s Executive Director Michael Brune, Paul Miller, also known as DJ Spooky, and Rue Mapp, the founder of Outdoor Afro, headed for some high ground behind our first camp to get a vantage for potential wildlife sightings.

 

 

Members of the Porcupine Caribou Herd are seen on their annual migration from the interior of Canada to the coastal plain of the Arctic National Wildlife Refuge, a migration of about 1,500 miles each year. The current population estimate of the Porcupine Caribou Herd puts them at a healthy level of 197,000 animals — the highest-observed amount since the census began. There were a few thousand that treaded quietly and passed us by.

 

 

The Arctic tundra is a fertile ground for some hearty wild flowers that take advantage of the short but intense growing season. Here Arctic lupine (lupinus articus) fill the scene.

 

 

Signs of caribou are found throughout the landscape of the refuge — from discarded antlers like this one, to permanent trails etched into the mountainsides over decades.

 

 

In the land of the midnight sun, inspiration was not hard to find. The Arctic Circle is the latitude at roughly the 66th parallel where the sun does not set below the horizon on June 21st, the summer solstice. We were further north of the Arctic Circle so the sun never set during our entire trip.

 

 

This grizzly bear blessed our Arctic trip, but it luckily just checked out our camp and passed us by. In the Arctic, the scarcity of food supports smaller grizzly bears of about 6 feet and 500 pounds with a range that can reach 5,000 square miles — compare that to coastal grizzlies in Alaska at 8 feet, 900 pounds, and roaming just 10 square miles!

 

 

The Arctic’s cold temperatures and permafrost in the ground cannot support trees, which adds to the vastness of the view as Brune gazes upon the horizon.

 

 

You can get a sense of the scale of the landscape as we put in one of our rafts into the Aichilik River. The Aichilik River forms in the Romanzof Mountains of the Brooks Range and flows 75 miles through the Arctic Refuge into the Beaufort Sea.

 

 

This is not your average river ice, but it is called "Aufeis." Aufeis is created from layers upon layers of snow and ice that collect and compress during the long winter months.

 

 

This view gazes over the fertile tundra of the coastal plain south to the expanse of the Brooks Range and through the ever-changing weather of America’s Arctic.

 

 

This is an impressive view of caribou seen just beyond the Aufeis in the Aichillik River. The Porcupine Caribou Herd has support the indigenous people in the region for time immemorial, and today both Inupiaq and Gwich’in communities continue to stay connected to the caribou through their cultures and for subsistence.

 

 

Though we were in the refuge for a week, we never took the scenery for granted.

 

 

This is a view of a crevice in the Aufeis. Some areas of Aufeis melt with the summer sun, but Aufeis in other shaded areas can last all year.

 

 

The Aichillik River took us from the mountains of the Brooks Range to the coastal plain of the Arctic Refuge, following as best we could the migration of the caribou from the interior of the state and heading north to the Arctic Ocean. The coastal plain is the biological heart of the refuge, where caribou migrate to calve their young, where polar bears den their cubs, and where millions of birds migrate from all 50 states to nest each year.

 

 

It’s amazing what you discover that you don’t need while camping in the wilderness, but equally as exciting to realize that you do have everything you need on one raft.