The glaciated Brooks Range separates Interior Alaska from Arctic Alaska. Stretching for 600 miles across the Arctic, the Brooks Range encompasses the Arctic National Wildlife Refuge (ANWR), the Gates of the Arctic National Park and Preserve and the Noatak National Preserve.

The mountains of the Brooks Range extend 75 miles east to west, rising from the tundra covered plain to tower 9,000 feet in rugged peaks and glaciers. Its highest elevations are in the east near the border with the Yukon Territory, reaching west almost as far as the Chukchi Sea to the west.

ANWR: The Arctic National Wildlife Refuge

mountainsThe Artic National Wildlife Refuge (ANWR) is located in the easternmost part of the Brooks Range, adjacent to the US border with Canada. The Refuge is recognized as one of the finest examples of wilderness left on this planet. It was among the last areas in North America to be visited by modern man and is among the least affected by his impact. ANWR is a place where the wild has not been taken out of the wilderness.

First set aside in 1960 to preserve its unique values, the Refuge more than doubled in size with the passage of the Alaska National Lands Conservation Act in 1980. Today the Refuge, vast and remote, spans nearly 20 million acres and is a place of reflection, beauty, and adventure.

The Refuge contains a wildlife diversity unparalleled anywhere else in the circumpolar north. The ancestral calving grounds of the 125,000 member Porcupine caribou herd lie in the northern reaches of the Refuge where, each year in early June, the herd migrates almost 800 miles to bear their young on the coastal plain. Age-old struggles for survival continue just as they always have in this special place. Grizzlies chase ground squirrels, digging like backhoes into their burrows. Wolf packs pursue caribou and moose, seeking those unable to keep up or defend themselves. Weasels and fox pounce on voles and lemmings.

Grizzly BearBlanketed with snow for much of the year, the Coastal Plain explodes with life during the brief spring and summer months, earning the nickname of “America’s Serengeti.”
The Porcupine River herd of 129,000 caribou gathers annually on the Coastal Plain to bear and nurse their young;
Polar bears rely on the Coastal Plain of the Refuge as their most important on-land denning habitat on American soil;
Musk oxen, grizzly bears, wolves, wolverines, foxes, golden eagles, and snowy owls gather here to hunt and den.
In the fall, the Coastal Plain of the Refuge supports up to 300,000 snow geese which detour to feed from their nesting grounds in Canada.
Millions of other birds use the Arctic Refuge to nest and as a critical staging area before journeying through every state.

Nearly 180 species of birds have been seen in the Arctic Refuge flying here from four continents to breed, rest or feed. Owls and jaegers cruise low over the tundra hunting for lemmings. Golden eagles, rough-legged hawks and peregrine falcons build aeries high on cliffs. Loons and oldsquaw sound their yodeling calls from coastal lagoons. Pairs of tundra swans dine on submerged plants in the quiet lakes or river deltas. By mid- september, most birds depart for wintering areas in Asia, Africa, South America, the South Pacific and every state except Hawaii. Ptarmigan, ravens, gyrfalcons, dippers and a few other species remain to winter in the long arctic night.


The Gates of the Artic National Park and Preserve includes about 8.2 million acres of public land with approximately 7.2 million acres designated as wilderness. Lying within its boundaries are six Rivers, 2 National Natural Landmarks and the Noatak Biosphere Reserve. Contiguous with the 5.6 million acres of designated wilderness in the Noatak National Preserve to the west, this rugged landscape is one of the world’s largest nature preserves. No roads lead into the park, and there are no trails or bridges inside.

A total of 133 species of birds have been observed in the park and preserve over the past 25-30 years. Nearly half of those recorded are normally associated with aquatic habitats.

Raptors inhabiting the park include species of eagles, hawks, falcons, and owls, three jaegers, and the northern shrike. Because of their place high in the food chain, raptors are more susceptible to environmental disturbance and population fluctuations. Arctic peregrine falcons, a threatened species only recently removed from the endangered list, nest in the area.


Camp at river sideThe western Brooks Range consists of the Baird and DeLong Mountains and is drained by the Noatak River. The Noatak and Kobuk Rivers begin in the Arrigetch Peaks in the Gates of the Arctic National Park and flow westward across the Brooks Range for more than 300 miles (480 km) to Kotzebue Sound. The Noatak River, the northernmost of the two rivers, flows for more than 200 miles (320 km) through the remote wilderness of Noatak National Park. The Kobuk River parallels the southern slopes of the Baird Mountains, passing Eskimo villages and through the southern edge of Kobuk Valley National Park. Popular among boaters of all sorts, these two rivers have excellent fishing for Arctic Grayling and Arctic Char and Sheefish, respectively, as well as top wildlife viewing (moose, caribou, wolves, sheep, foxes and birds).


River campAmong the many flowing northward out of the valleys of the eastern Brooks Range across the tundra to the Arctic Ocean are three special rivers, the Canning, Hulahula, and the Kongakut. These rivers provide unique opportunities to see nature in it’s most raw and undisturbed state, abundant wildlife and scenic landscape vistas. A trip down one of these rivers often showcases migrating caribou, moose, musk ox, Dall sheep, wolves, grizzly bears, and waterfowl.

In the Brooks Range, including the Artic National Wildlife Refuge, are places that change those who visit them. Their existence strengthens our awareness of – and sense of – responsibility to the natural world. Isuma Guideworks is honored to introduce you to this magnificent part of Alaska, a wild land which both humbles us and allows us to sense so deeply our membership in the community of life.