GMU 423 Henry
A tiny, boat-only, all-private San Juan blacktail island
WDFW Region 4 — North Puget Sound (District 13, San Juan County) · Last reviewed 2026-07-12
Area
1
sq mi
Public land
0%
approx.
Elevation
0–250
feet
Motorized
limited
access
Overview
GMU 423 is Henry Island, a small San Juan County island tucked against the northwest shoulder of San Juan Island near Roche Harbor. WDFW split it into its own unit in 2021 to sharpen harvest reporting. The only big-game opportunity is Columbian black-tailed deer; there is no elk, bear or cougar. Henry is not served by the state ferry and is essentially all private, so this is one of the harder-to-access units in the state — you need a boat and written landowner permission before you can hunt a single acre.
Terrain
A low, roughly wing-shaped island of a few hundred acres rising modestly from Haro Strait and Roche Harbor, with rocky, madrona-fringed shoreline and gentle forested interior knolls.
Cover: Douglas-fir and Pacific madrona forest with open grassy balds and salal understory typical of the San Juans, interspersed with private homesteads and cleared parcels.
Landmarks: Roche Harbor (adjacent, on San Juan Island) · Haro Strait · Mosquito Pass · Open Bay · Nelson Bay
Access
WDFW notes very little public land exists anywhere in San Juan County and firearm restrictions apply throughout. Henry Island has no state ferry service — access is by private boat or commercial water taxi only, and most docks and landings in the San Juans are privately owned. Essentially all of the island is private, and by San Juan County ordinance hunting on private land requires WRITTEN landowner permission. Practically, hunting here means arranging both boat access and a specific written permission in advance; there is no walk-in public ground.
Managers: Private (residential / estate)
Access points: Private boat from Roche Harbor / San Juan Island · Commercial water taxi · Private docks (permission required)
Species notes
Blacktail Deer
common opportunityColumbian black-tailed deer inhabit Henry Island and, like the rest of the archipelago, have historically been overabundant — though the 2021 Adenovirus Hemorrhagic Disease (AHD) outbreak that swept the San Juans reduced numbers on Henry among other islands. Island bucks run smaller than mainland blacktails. Opportunity is real but gated entirely by private access.
- →Secure written landowner permission AND boat/water-taxi access before the season — nothing else matters here
- →Hunt forest-edge and grassy bald transitions where San Juan blacktails feed morning and evening
- →Expect smaller-bodied island deer; manage expectations on antler size
- →Be alert for AHD-weakened or sick deer and use disposable gloves; avoid harvesting obviously infected animals
- →Keep every setup mindful of homes and outbuildings on this heavily parceled island
Pro tips
- →Lock down written landowner permission first — San Juan County ordinance requires it and there is no public land fallback
- →Line up boat or water-taxi transport and a legal landing before you commit to the hunt
- →Assume smaller island-blacktail body and antler size than the mainland
- →Carry gloves and watch for AHD symptoms; the disease hit Henry in the 2021 outbreak
- →Confirm San Juan County firearm-restriction rules for your specific parcel before hunting
Watch out for
- !Zero public land — 100% private, written permission legally required to hunt
- !No ferry service; boat or water-taxi access only, and most docks are private
- !County-wide firearm restrictions and dense parcelization limit legal discharge
- !AHD (adenovirus) has periodically knocked down island deer numbers
- !No elk, bear or cougar — blacktail deer is the sole opportunity
Logistics
Stage out of Roche Harbor or Friday Harbor on San Juan Island (reached by Washington State Ferry from Anacortes), then cross to Henry by private boat or water taxi. There is no public moorage, camping, or services on Henry itself — this is a day-hunt off a pre-arranged landing.
Nearest towns: Roche Harbor, Friday Harbor, Anacortes (mainland ferry hub)
Nearby units
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Washington sources:
Research sources: WDFW 2025 District 13 Hunting Prospects (San Juan / Island counties) · WDFW Game Management Units (GMU) directory
FAQ
- How big is GMU 423 in Washington?
- GMU 423 (Henry) covers about 1 square miles, ranging from roughly 0 to 250 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 423?
- Approximately 0% of the unit is public land. Primary managers: Private (residential / estate). Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 423?
- Blacktail Deer. For seasons, tags, and regulations, use the official Washington agency resources linked on this page — this page carries no regulatory information.
Put GMU 423 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.