GMU 426 Diablo
The North Cascades high country — glaciated, roadless, and mostly national park; a low-opportunity trophy-blacktail and backcountry unit
WDFW Region 4 — North Puget Sound (District 14) · Last reviewed 2026-07-12
Area
319
sq mi
Public land
90%
approx.
Elevation
500–9,066
feet
Motorized
wilderness
access
Overview
GMU 426 (Diablo) is the wildest and least-accessible unit in District 14, occupying the upper Skagit high country of eastern Whatcom and Skagit counties around Newhalem, Diablo and Ross lakes and the crest of the North Cascades. Land ownership defines the hunt: much of the unit is North Cascades National Park, which is CLOSED to hunting, with the huntable ground confined to the Ross Lake National Recreation Area (where hunting is allowed) and adjacent Mt. Baker-Snoqualmie National Forest. Blacktail deer densities are reported down and the terrain is brutally steep and glaciated, so this is a low-density unit that rewards fit backcountry hunters over road hunters. There is no established elk herd here. Black bear are common — but this is a federally designated grizzly-bear recovery area, so a bear-ID exam is mandatory. Mountain goat live the crest but the season is closed. Realistically, 426 is a hard-country blacktail, bear and cougar unit for hunters who want solitude over odds.
Terrain
Extreme North Cascades relief — from the Skagit River near Newhalem (~500 ft) and Diablo Lake (~1,200 ft) up glaciated walls to peaks approaching and exceeding 9,000 ft (Jack Mountain 9,066 ft; Colonial, Ruby and Davis peaks). Deep forested valleys, hanging glaciers, avalanche chutes and knife-edge ridges; almost no vehicle access off the single highway corridor.
Cover: Lower western hemlock/Douglas-fir and Pacific silver fir forest along the Skagit and lake shores, grading up through subalpine fir and mountain hemlock into alpine heather, huckleberry basins, rock and permanent ice. Avalanche paths and old burns create the scattered browse and berry that hold deer and bear.
Landmarks: Diablo Lake · Ross Lake · Skagit River / Newhalem · Jack Mountain (9,066 ft) · Colonial Peak · Ross Lake National Recreation Area · North Cascades Highway (SR-20)
Access
Access is the defining challenge. The dominant landholder is North Cascades National Park, which is closed to hunting — legal hunting is limited to the Ross Lake National Recreation Area and the Mt. Baker-Snoqualmie National Forest, and hunters MUST know exactly where those boundaries fall. The only vehicle artery is the North Cascades Highway (SR-20); nearly everything off it is roadless wilderness or park requiring foot or boat travel (Ross Lake is accessed by trail or water). There is essentially no private-timber walk-in game here — this is a public-land, boots-and-boat backcountry unit. Contact the Mt. Baker-Snoqualmie NF (Darrington Ranger District 360-436-1155) and North Cascades National Park for current road, trail and boundary information before hunting.
Managers: North Cascades National Park (NPS — closed to hunting), Ross Lake National Recreation Area (NPS — hunting allowed), USFS Mt. Baker-Snoqualmie National Forest, WDNR
Access points: North Cascades Highway (SR-20) corridor — Newhalem, Diablo, Colonial Creek · Ross Lake NRA trailheads and boat access (hunting-allowed zone) · Mt. Baker-Snoqualmie NF trailheads off SR-20 · Backcountry trails into the high basins (foot access)
Species notes
Blacktail Deer
limited opportunityBlacktail densities in 426 are reported down and the huntable ground is a fraction of the unit, so general opportunity is thin. The real draw is the permit-only late 'quality buck' rut hunt — 2024 permit success was 10%, the lowest of the district's three quality-buck GMUs but a shot at a mature backcountry buck. This is a transitional crest unit; deer are blacktail, concentrated in avalanche chutes, burns and subalpine basins reachable only on foot.
- →Hunt on your legs — glass alpine and subalpine basins, avalanche chutes and burn edges that hold browse well above the highway
- →Focus effort inside the Ross Lake NRA and national-forest ground; the national park itself is closed
- →Use a boat or the long trails to reach lightly hunted Ross Lake shoreline benches
- →The late quality-buck permit targets the rut — hunt ridge and basin margins in the November window
- →Expect low deer density; success here is earned with fitness and scouting, not road glassing
Black Bear
common opportunityBlack bear are common in the North Cascades forests and huckleberry high country of 426, part of a District 14 harvest of 190 bears in 2024. Note this is a federally identified grizzly-bear recovery area (with the North Cascades Ecosystem an active NPS/USFWS restoration focus), so a bear-ID exam is mandatory before hunting.
- →Hunt the alpine and subalpine huckleberry fields early season for classic spot-and-stalk
- →Glass avalanche chutes, old cuts and burns on the forested slopes at first and last light
- →You MUST pass the WDFW online bear-identification exam (80%+) and carry proof — this is grizzly recovery country
- →Submit the required premolar tooth after a successful fall hunt
Cougar
common opportunityCougar range the unit following the blacktail and are taken opportunistically. GMUs 426 and 437 share a combined cougar harvest cap of 9 for 2025 that can close the season mid-hunt.
- →Hunt where deer concentrate along the forested benches and basins
- →Verify the combined 426/437 cap hasn't closed the season before a late hunt via the cougar hotline (1-866-364-4868, press 2)
- →Fresh snow aids tracking; no dogs allowed statewide
Mountain Goat
common lowMountain goats inhabit the North Cascades crest within the unit, but goat seasons in the surrounding North Cascades hunt areas have been closed due to a well-documented, region-wide population decline. There is currently no general or permit goat harvest opportunity here — the animals are present but not huntable.
- →No open season — treat goats as wildlife to observe, not hunt
- →Watch WDFW special-permit listings for any future reopening; North Cascades goat numbers remain depressed
Pro tips
- →Before anything else, map the North Cascades National Park boundary precisely — the park is closed to hunting and it dominates the unit; hunt only the Ross Lake NRA and national forest
- →This is a backcountry-fitness unit — the hunters who succeed hike or boat well past the SR-20 corridor into basins nobody else reaches
- →Pass the WDFW bear-ID exam and carry proof; 426 sits in the North Cascades grizzly recovery area
- →Ross Lake shoreline benches reached by boat or trail see far less pressure than the roadside
- →Set expectations honestly: low deer density and a tiny huntable footprint mean this is a solitude-and-adventure unit, not a numbers unit
Watch out for
- !North Cascades National Park is CLOSED to hunting and covers much of the unit — hunting there is illegal; only Ross Lake NRA and national forest are open
- !Grizzly recovery area — mandatory bear-ID exam, and grizzly presence/restoration is an active management topic
- !Almost no vehicle access off SR-20; the high country is roadless wilderness reached only on foot or by boat
- !SR-20 closes seasonally over the passes with snow, sealing the eastern approach
- !No cell coverage and true backcountry hazards — glaciers, avalanche terrain, swift rivers, and dry-fall fire closures
Logistics
This is a remote unit with minimal services — Marblemount is the last practical stop for fuel and basics on the west approach, with Sedro-Woolley and Concrete downriver for full supplies and Winthrop over Washington Pass to the east. North Cascades NP and NRA campgrounds line SR-20 near Newhalem, Diablo and Colonial Creek. There is no cell coverage through most of the corridor; carry a paper map, know the park/NRA/forest boundaries, and plan for self-sufficient backcountry travel.
Nearest towns: Newhalem, Marblemount, Concrete, Sedro-Woolley, Winthrop
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Washington sources:
Research sources: WDFW 2025 District 14 Hunting Prospects (Skagit & Whatcom) · WDFW Game Management Units · National Park Service — North Cascades hunting regulations
FAQ
- How big is GMU 426 in Washington?
- GMU 426 (Diablo) covers about 319 square miles, ranging from roughly 500 to 9,066 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 426?
- Approximately 90% of the unit is public land. Primary managers: North Cascades National Park (NPS — closed to hunting), Ross Lake National Recreation Area (NPS — hunting allowed), USFS Mt. Baker-Snoqualmie National Forest, WDNR. Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 426?
- Blacktail Deer, Black Bear, Cougar, Mountain Goat. For seasons, tags, and regulations, use the official Washington agency resources linked on this page — this page carries no regulatory information.
Put GMU 426 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.