Lake Clark National Park & Preserve

Alaska · Established December 2, 1980

Steaming volcanoes, salmon lakes, and bears on the edge of Cook Inlet

Area: 2,619,816 acres
Established: December 2, 1980
Recreation visits: 19,778 / yr
State: Alaska
Highest point: Mount Redoubt, 10,197 ft (3,108 m)
Lowest point: Sea level along Cook Inlet

Lake Clark Weather Forecast

Loading the National Weather Service forecast for Lake Clark…

Seven-day outlook at the park's reference point (60.574, -153.555). Elevation changes everything in the mountains — expect colder, windier and wetter conditions on high ground.

Map of Lake Clark National Park & Preserve

The Park

Lake Clark is Alaska in miniature, a place where nearly every kind of Alaskan landscape crowds into one roadless park southwest of Anchorage. Along Cook Inlet, brown bears graze sedge meadows below a pair of smoking volcanoes; across the mountains, the land opens into spruce forest, tundra, and long glacial lakes that feed one of the richest sockeye salmon fisheries on Earth.

The park was established on December 2, 1980, and can be reached only by small plane or boat. Its heart is the Chigmit Mountains, where the Alaska and Aleutian ranges meet, and its namesake lake became widely known through Richard Proenneke, who built a log cabin by hand at nearby Twin Lakes and lived there for three decades.

Geography

Lake Clark National Park and Preserve covers about 4 million acres on the west side of Cook Inlet, of which some 2.6 million acres are national park. The Chigmit Mountains form the park's spine, linking the Aleutian Range to the south with the Alaska Range to the north, while the Neacola Mountains rise to the northwest. Ice fields and valley glaciers cap the highest ground, and two great stratovolcanoes, Redoubt and Iliamna, stand near the coast.

The mountains divide the park into two very different halves. The eastern coast is a lowland of tidal bays, salt marsh, and rivers such as those draining into Tuxedni and Chinitna bays. West of the crest, rivers run toward Bristol Bay through a chain of large lakes. Lake Clark, more than 40 miles long, drains by way of the Newhalen River into Iliamna Lake, and from there to the Kvichak River and the sea.

Landmarks

Mount RedoubtVolcano · 10,197 ftThe park's highest summit and most active volcano, which erupted in 1989–1990 and again in 2009.
Mount IliamnaVolcano · 10,016 ftA glacier-clad stratovolcano whose summit fumaroles often trail plumes of steam.
Lake ClarkLakeThe park's namesake lake, a long glacier-fed trough lying along the Lake Clark Fault.
Twin LakesLakeRemote mountain lakes where Richard Proenneke built his log cabin in 1968.
Kontrashibuna LakeLakeA narrow, steep-walled lake in a glacial valley south of Lake Clark.
Crescent LakeLakeA coastal-side lake known for brown bears fishing for sockeye salmon in summer.
Chigmit MountainsPeakThe rugged, glaciated range where the Alaska and Aleutian ranges join.
Neacola MountainsPeakA granitic range of spires and glaciers in the park's northern reaches.
Tlikakila RiverRiverA braided, silt-laden wild river flowing from glaciers into upper Lake Clark.
Lake Clark PassValleyA narrow, glacier-lined flight corridor through the mountains between Anchorage and the Lake Clark country.
Tuxedni BayCoastA broad Cook Inlet bay where brown bears feed on sedges and clams at low tide.
Chinitna BayCoastA tidal bay on the park's southern coast with wide meadows favored by grazing bears.
Port AlsworthAreaA small community on the shore of Lake Clark and the site of the park's field headquarters and visitor center.

Geology

Lake Clark lies above one of the most active plate boundaries on the planet. The Pacific Plate dives beneath southern Alaska at roughly 7 centimeters a year, and that descent has fed volcanoes here for well over 100 million years. In the Jurassic, an arc of island volcanoes spread the lavas and ash of the Talkeetna Formation, while magma that never reached the surface cooled into the granites and diorites of the Alaska-Aleutian Range batholith. The oldest of those plutons formed roughly 176 to 154 million years ago, and new pulses of magma arrived in later ages, some as recently as about 38 to 26 million years ago.

The mountains are also sliced by long faults. The Lake Clark Fault, about 140 miles long, runs beneath Lake Clark and Lake Clark Pass and has shifted the land on either side horizontally by several miles, while the Bruin Bay Fault traces the coastal side of the range for hundreds of miles. Along the coast, sedimentary rocks laid down in Jurassic seas preserve ammonites, belemnites, and clams.

The volcanoes Redoubt and Iliamna are the modern expression of the subduction zone. Redoubt, the more restless of the two, has erupted several times in living memory, raining ash on Cook Inlet communities and sending mudflows down the Drift River. Ice completed the landscape: Pleistocene glaciers poured out of the mountains, scouring the long troughs now filled by Lake Clark, Kontrashibuna, and Twin Lakes, and glaciers still flow from the high Chigmits today.

Deep time

Jurassic, about 176 to 154 million years agoThe oldest plutons of the Alaska-Aleutian Range batholith crystallize beneath a volcanic arc.
JurassicIsland-arc volcanoes build the Talkeetna Formation, and nearby seas bury ammonites and belemnites in coastal sediments.
About 38 to 26 million years agoA later pulse of granitic magma intrudes the batholith.
PleistoceneLarge glaciers carve the deep valleys that now hold Lake Clark and the park's other long lakes.
1989 to 1990Mount Redoubt erupts, sending ash over Cook Inlet and disrupting air travel.
2009Redoubt erupts again with a series of explosive events and lahars down the Drift River valley.

The rocks

Alaska-Aleutian Range batholithJurassic to Tertiary
A vast complex of granite, granodiorite, and diorite forming the core of the Chigmit Mountains.
Talkeetna FormationEarly Jurassic
Volcanic flows and volcaniclastic rocks from an ancient island arc.
Tuxedni GroupMiddle Jurassic
Marine sedimentary rocks of the Cook Inlet coast that hold marine invertebrate fossils.
Lake Clark FaultCenozoic
A 140-mile strike-slip fault that controls the straight trough of Lake Clark and Lake Clark Pass.
Redoubt and Iliamna volcanic depositsQuaternary
Andesitic lavas, ash, and lahar deposits from the park's two stratovolcanoes.

Trees, Plants & Ecosystems

734vascular plant species recorded

Coastal salt marsh and sedge meadowsSea level
Tidal flats and lush sedge meadows along Cook Inlet provide spring grazing and clam digging for brown bears.
Boreal spruce and birch forestLowlands to about 2,000 ft
White and black spruce mix with birch and balsam poplar around the interior lakes and river valleys.
Alder and willow shrublandValley slopes and timberline
Dense thickets of alder and willow cloak avalanche paths and the zone above forest.
Alpine tundraUpper slopes
Low heaths, mountain avens, and lichens support Dall's sheep, ground-nesting birds, and hoary marmots.
Glaciers and ice fieldsHigh Chigmit and Neacola mountains
Permanent ice feeds silty rivers that carry sediment into the park's lakes.

Trees

White sprucePicea glaucaThe tall, dominant conifer of well-drained river terraces and lakeshores.
Black sprucePicea marianaA slender spruce of cold, boggy ground in the interior.
Alaska birchBetula neoalaskanaA white-barked birch that brightens the interior forest with gold in September.
Kenai birchBetula kenaicaA birch of south-central Alaska that grows in mixed forest near the coast and lakes.
Balsam poplar and black cottonwoodPopulus balsamiferaFragrant, fast-growing trees of river floodplains.
Feltleaf willowSalix alaxensisA tall willow of gravel bars and a staple food for moose.
Sitka alderAlnus viridisA tangled shrub-tree that forms dense belts on mountain slopes.

Wildflowers, shrubs & other plants

FireweedChamerion angustifoliumMagenta spires that color burns, roadsides, and clearings all summer.
Nootka lupineLupinus nootkatensisBlue lupines crowd coastal meadows in early summer.
Beachhead irisIris setosaA purple wild iris of wet coastal meadows.
Chocolate lilyFritillaria camschatcensisDark maroon bells in coastal grasslands.
Cow parsnipHeracleum maximumA towering plant whose stems bears eat, and whose sap can burn skin in sunlight.
BunchberryCornus canadensisA tiny dogwood carpeting the forest floor with white bracts and red berries.
Black crowberryEmpetrum nigrumA low evergreen berry plant of tundra and bogs.
Bog blueberryVaccinium uliginosumLate-summer berries relished by bears and birds.
SalmonberryRubus spectabilisOrange to red berries in moist coastal thickets.
Eightpetal mountain-avensDryas octopetalaA mat-forming tundra plant with white flowers and feathery seedheads.
Larkspurleaf monkshoodAconitum delphiniifoliumDeep blue hooded flowers of meadows and thickets; highly poisonous.
Bluejoint reedgrassCalamagrostis canadensisA tall grass forming extensive meadows in wet openings.
American dunegrassLeymus mollisA coarse grass that stabilizes beaches along Cook Inlet.

Wildlife

36mammals
158birds
1amphibians
43fish

Mammals

Brown bearUrsus arctosCoastal bears gather in sedge meadows and at salmon streams, the park's most famous sight.
American black bearUrsus americanusMore common in the forested interior.
MooseAlces alcesBrowses willows along lakeshores and rivers.
CaribouRangifer tarandusRoams the western tundra and foothills of the preserve.
Dall's sheepOvis dalliWhite wild sheep on high, rugged slopes.
Gray wolfCanis lupusPacks range widely through the interior.
Red foxVulpes vulpesFrequently seen hunting in coastal meadows.
WolverineGulo guloA rarely seen, wide-ranging scavenger of the mountains.
Canada lynxLynx canadensisA snowshoe-hare specialist of the boreal forest.
American beaverCastor canadensisBuilds lodges and dams on quiet ponds and sloughs.
Hoary marmotMarmota caligataLives among alpine boulder fields.
Northern sea otterEnhydra lutrisFloats in kelp and nearshore waters along the coast.
Harbor sealPhoca vitulinaHauls out on coastal rocks and sandbars.
Beluga whaleDelphinapterus leucasThe endangered Cook Inlet beluga population uses waters off the park's coast.

Birds

Bald eagleHaliaeetus leucocephalusCommon along the coast and salmon rivers.
Trumpeter swanCygnus buccinatorNorth America's largest waterfowl, nesting on interior ponds.
Pacific loonGavia pacificaIts haunting calls carry across tundra lakes.
Willow ptarmiganLagopus lagopusAlaska's state bird, turning white in winter.
Horned puffinFratercula corniculataNests on coastal cliffs along Cook Inlet.
Tufted puffinFratercula cirrhataA seabird with golden head plumes in breeding season.
Harlequin duckHistrionicus histrionicusBreeds on rushing mountain streams, wintering on rocky coast.
American dipperCinclus mexicanusDives in clear, fast streams year-round.
Peregrine falconFalco peregrinusNests on cliffs and hunts shorebirds and ducks.
OspreyPandion haliaetusA fish hawk of the interior lakes.
Boreal chickadeePoecile hudsonicaA brown-capped chickadee of spruce forest.
Canada jayPerisoreus canadensisA year-round resident that caches food for winter.
WhimbrelNumenius phaeopusA curve-billed shorebird of tidal flats and tundra.
Common eiderSomateria mollissimaA large sea duck of coastal waters.

Reptiles & amphibians

Wood frogRana sylvaticaThe park's only amphibian, able to survive being frozen solid through winter.

Fish

Sockeye salmonOncorhynchus nerkaMillions return to the Kvichak watershed; Lake Clark's tributaries are vital spawning and rearing waters.
Chinook salmonOncorhynchus tshawytschaThe largest Pacific salmon, running in coastal and interior rivers.
Coho salmonOncorhynchus kisutchLate-summer runs enter coastal streams such as those at Silver Salmon Creek.
Arctic graylingThymallus arcticusA sail-finned fish of clear streams.
Lake troutSalvelinus namaycushA large char of deep, cold lakes.
Rainbow troutOncorhynchus mykissNative to the Bristol Bay drainage of the interior.
Northern pikeEsox luciusAn ambush predator of weedy lake margins.
Dolly VardenSalvelinus malmaA char that follows salmon runs to feed on eggs.

Species totals are the park's certified NPSpecies checklist (occurrence: present).

Climate & When to Visit

The Chigmit Mountains create two distinct climates in Lake Clark. The Cook Inlet coast is maritime: cloudy, wet, and relatively mild, with frequent rain and fog carried in by storms from the Gulf of Alaska. West of the mountains, the interior around Lake Clark and Twin Lakes receives only a quarter to a half as much precipitation, but its temperatures swing much further, warmer in summer and markedly colder in winter.

Frost and snow are possible anywhere in the park at any time of year, though they are most likely from September to early June. The large lakes typically begin freezing in November and break up in April, and that transition matters: bush planes need floats in open-water season and skis once the ice is solid. Wind is a constant companion in mountain passes, and Lake Clark Pass is notorious among pilots for low clouds and turbulence.

Spring
Lake ice breaks up around April and May; bears emerge and graze fresh sedges on the coast, but snow lingers inland.
Summer
June through August brings long daylight, the mildest temperatures, and the main season for bear viewing, fishing, and hiking; the coast can be rainy and foggy.
Autumn
Birch and willow turn gold in September, silver salmon run, and the first snows dust the peaks as storms strengthen.
Winter
Long, cold, and dark in the interior; lakes freeze by November and travel shifts to ski-equipped aircraft.

Weather hazards

Flight weather delays: Low clouds and wind frequently ground small planes, so build extra days into any trip.
Hypothermia: Cold rain and wind can chill you quickly even in summer; waterproof layers are essential.
Cold lakes and rivers: Glacial waters are frigid and swift, making capsizing or falling in a life-threatening emergency.
Bear encounters: Brown bears are abundant, so carry bear spray, store food properly, and keep your distance.
Volcanic ash: Redoubt and Iliamna are active; check Alaska Volcano Observatory alerts before flying in.

Lake Clark Questions

When is the best time to visit Lake Clark National Park?

June through August is the prime season, with long days, open lakes for floatplanes, and the best bear viewing. September brings fall color and fewer visitors but more rain and wind.

How do you get to Lake Clark National Park?

There are no roads into the park. Most visitors fly in by small plane from Anchorage, Homer, or Kenai, landing at Port Alsworth, on lakes, or on coastal beaches.

Where is the best bear viewing in the park?

The Cook Inlet coast is best, particularly the meadows around Chinitna Bay, Silver Salmon Creek, and Crescent Lake. Brown bears graze sedges in early summer and fish for salmon later in the season.

What is the weather like at Lake Clark?

The coast is wetter and milder, while the interior west of the mountains is drier but has hotter summers and colder winters. Snow and frost can occur at any time of year, most often from September to early June.

Are the volcanoes at Lake Clark active?

Yes. Mount Redoubt erupted in 1989 to 1990 and again in 2009, and Mount Iliamna often vents steam from its summit. Both are monitored by the Alaska Volcano Observatory.

Who was Richard Proenneke?

Proenneke was a self-taught naturalist who built a log cabin by hand at Twin Lakes beginning in 1968 and lived there until 1999. His films and journals made the Lake Clark wilderness famous, and his cabin is preserved in the park.

More parks in the Alaska

← Kobuk Valley National Park Lassen Volcanic National Park →

Sources: www.nps.gov · www.nps.gov · en.wikipedia.org · pubs.usgs.gov · irmaservices.nps.gov · Official NPS site