Guam & the Northern Mariana Islands Fishing Guide

Guam and the Northern Marianas have deep water close to shore, and trolling for mahi-mahi, wahoo, tuna and blue marlin goes on year-round. Guam's five marine preserves ban most fishing, and the CNMI has five no-take areas plus bans on SCUBA spearfishing and gill nets. Guam is working on a new reef fish plan in 2026 that may add licenses and size limits, so check current rules.

📍 Guam and the Commonwealth of the Northern Mariana Islands (Saipan, Tinian, Rota) in the western Pacific Mariana Archipelago. Trollers usually fish 5-8 miles from shore, up to about 30 miles; Guam's southern banks (Galvez, Santa Rosa and others) are often closed by military live-fire training.

Map: spots, ramps and marinas

★ Fishing hot spot · ● Boat ramp · ● Marina · ▭ Protected area (solid red = no fishing, dashed = fishing with rules)

Open the full Guam & Northern Mariana Islands map →

Quick facts

Guam has five marine preserves: Tumon Bay, Piti Bomb Holes, Sasa Bay, Achang Reef Flat and Pati Point.
About 447 boats took part in Guam's pelagic troll fishery in 2024, targeting mahi-mahi, wahoo, skipjack, yellowfin and blue marlin.
SCUBA spearfishing became illegal on Guam in May 2020.
The CNMI has five no-take marine areas: Mañagaha, Bird Island and Forbidden Island (Saipan), Sasanhaya Bay (Rota) and the Tinian Marine Reserve.
Guam's Piti Bomb Holes preserve (1999) covers about 900 acres and has the Fish Eye underwater observatory.

What you can catch

Mahi-mahi
Most abundant in winter and early spring near Guam.
Wahoo
Catch rates peak in November and December.
Blue marlin
More common in summer.
Skipjack tuna
More common in summer; also caught around FADs.
Yellowfin tuna
More common in summer.
Dogtooth tuna
Found over reefs and deep water year-round.
Deep-water snappers and groupers
Guam bottomfish; mostly handline on offshore banks.
Seasonal juvenile fish (ti'ao, i'e, atulai)
Seasonal runs; special permits may open some preserves to hook and line and cast net.

Month by month

January	Mahi-mahi season (winter-spring).
February	Mahi-mahi season.
March	Mahi-mahi season; special permits have opened Achang and Piti preserves for seasonal juvenile fish in some years.
April	Mahi-mahi season into early spring.
May	Trolling year-round; ask what is running.
June	Summer season for blue marlin, skipjack and yellowfin starts.
July	Blue marlin, skipjack and yellowfin.
August	Blue marlin, skipjack and yellowfin.
September	Blue marlin, skipjack and yellowfin.
October	Late summer tuna and marlin.
November	Wahoo peak.
December	Wahoo peak; mahi-mahi season starts.

Tips

Learn the preserve boundaries before fishing; Guam preserves run from 10 m inland of high tide out to the 600-foot depth line.
At Pati Point only hook and line from shore is allowed; in Tumon Bay shore fishing is limited to a few species and bottomfishing only beyond 100 feet deep.
Inside Guam preserves, trolling from the reef margin seaward is for pelagic fish only; release any reef fish at once.
Guam shallow-water moorings have a 3-hour limit and are for boats up to 50 feet.
In the CNMI, a license is needed to use a cast net (talaya); no SCUBA or hookah spearfishing and no gill nets.

Rules and license

Guam Department of Agriculture, Division of Aquatic and Wildlife Resources (DAWR); CNMI DLNR Division of Fish and Wildlife; NOAA Fisheries / Western Pacific Fishery Management Council (federal waters) · Official rules page ↗

Guam preserves: no spearfishing, gaffs, gill, drag, dip or surround nets, shell collecting or gleaning in any preserve.
Piti, Sasa Bay and Achang: all fishing banned except methods allowed by law or permit; Pati Point: shore hook and line only.
Guam: SCUBA spearfishing banned (May 2020); size limits on lobsters and crabs; no taking berried crustaceans. Check current numbers with DAWR.
Guam: a general recreational license was not confirmed; the 2026 Coastal Fisheries Management Plan proposes mandatory licenses, size limits for 9 reef fish and full protection for humphead parrotfish. Check current rules.
Guam waters 0-3 nm are territorial; 3-200 nm are federal waters.
CNMI: no-take at Mañagaha, Bird Island, Forbidden Island, Sasanhaya Bay and Tinian (Tinian allows seasonal atulai, i'i' and ti'ao).
CNMI: cast-net license $10 residents / $75 non-residents; lobster minimum 3-inch carapace; trochus and sea cucumber harvest banned.
CNMI: no SCUBA or hookah spearfishing, explosives, poisons, gill nets, drag nets or trap nets.

Rules change. Always check the official page before you fish.

Boat ramps and marinas

The map above shows 9 boat ramps and 2 marinas from OpenStreetMap. Tap any dot for directions.

Agat Small Boat Harbor
Boat ramp near Agfayan Bay
Boat ramp near Dog Leg Pier
Boat ramp near East Basin
Boat ramp near Port Merizo
Boat ramp near Umatac Bay
Harbor of Refuge

Sources

Checked October 2026. BigJoe does not invent facts: every number on this page comes from the sources listed above.