Drive offshore from Phuket or Khao Lak on any calm morning from December through March, and within an hour you may encounter a sight that has shaped pelagic fishing in Thailand for generations: a lone buoy or cluster of floating debris sitting over open blue water, surrounded by a haze of seabirds and the occasional surface boil of fish chasing bait. This is a FAD — a Fish Aggregating Device — and the concentrated predator activity around it is one of the most reliable and accessible forms of big-game fishing in the country.
Understanding how FADs work, what they attract, and how to fish them responsibly puts an entirely different category of species within reach of anglers who might otherwise spend a day blind-trolling across empty water.
What Is a FAD and Why Does It Work?
The principle behind FADs is one of the ocean's most reliable patterns: life attracts life. In the open Andaman Sea and Gulf of Thailand, the water column is largely featureless — there is no reef, no rock, no structure to concentrate organisms. A floating object changes this immediately.
Within days of a buoy or debris piece becoming established at a location, microscopic organisms begin to accumulate in its shade and against its surface. Small invertebrates follow. Juvenile fish arrive to shelter from predators in the object's shadow. Larger fish come to eat the juveniles. And the largest pelagics — tuna, mahi-mahi, wahoo — arrive to eat everything else.
The structure that forms around a well-established FAD can be extraordinary. On a productive day, you might find hundreds of metres of accumulated bait and predator life in water that, without the FAD, holds nothing visible at all. The aggregation is not random; it is a concentrated expression of the same dynamics that make a reef productive, compressed around a single artificial anchor point.
FAD locations are not publicly mapped and change over time as buoys drift or sink. Charter operators maintain their own knowledge of current productive FAD positions. When booking a FAD-focused trip, ask specifically whether the operator targets known buoys or runs a more opportunistic approach.
Target Species
Yellowfin Tuna
Yellowfin tuna are the headline species at Andaman FADs. They are not always present — yellowfin move through the area rather than holding permanently — but when the stars align, a productive FAD can hold dozens of fish in the 5–30kg class within casting or trolling range.
Yellowfin at FADs behave differently from open-water fish. They are more approachable, less likely to sound immediately when disturbed, and more responsive to a range of presentations. Live bait — a frigate mackerel or small tuna suspended at 20–40 metres — is among the most effective methods. Trolling skirted lures through the active zone also produces fish, particularly when the school is widely distributed around the FAD.
When yellowfin are visibly feeding on the surface — a boiling, frenzied push of silver bait with dark shapes knifing through below — casting poppers or stickbaits into the melee can produce explosive surface strikes. Light jigging with slender metal lures worked through the mid-water column is also effective.
Mahi-Mahi and Dolphinfish
Mahi-mahi are arguably the most reliable FAD species in Thai waters. Their strong association with floating objects is well documented globally, and the Andaman is no exception. Schools of mahi-mahi — ranging from small juvenile fish to adult fish of 10kg and above — gather around buoys and debris with remarkable consistency.
They are aggressive, fast, and acrobatic when hooked, making them a popular target on lighter tackle. They respond enthusiastically to almost any lure or bait presented at or near the surface. Once you locate a school at a FAD, keeping at least one fish in the water (without landing it immediately) will often hold the rest of the school in the area — a useful technique when the fishing is good and you want to extend the session.
Longtail and Skipjack Tuna
Longtail tuna and skipjack are smaller than yellowfin but often present in much larger numbers around FADs. Skipjack in particular will form massive, fast-moving schools that erupt around buoys in a storm of silver and foam. They hit almost anything cast into the frenzy.
Both species are excellent on light tackle — 10–20lb spinning outfits and small metal jigs or surface lures produce outstanding sport. They are also superb live bait for larger yellowfin if you want to escalate the program mid-session.
Wahoo
Wahoo are less reliably found at FADs than the tuna species, but they do associate with floating objects and are occasionally encountered on FAD trips running between buoys. A wahoo on a trolled lure is among the fastest and most violent strikes in pelagic fishing — their initial run on heavy braid can empty a reel in seconds. High-speed trolling (8–12 knots) with skirted lures or diving bibbed minnows is the most consistent wahoo method.
Marlin and Sailfish
Marlin and sailfish are occasional visitors to FADs, particularly active structures with large accumulated baitfish populations. Billfish are not the primary target on most FAD trips, but encounters do happen. Trolling large skirted lures or rigged baits while transiting between FAD locations gives you a reasonable chance of a billfish strike en route.
A productive FAD can hold dozens of yellowfin tuna in the 5–30kg class within casting or trolling range — compressed into structure that, without the buoy, simply does not exist.
Technique: How to Fish a FAD
Approaching a FAD requires some care. Driving directly into the aggregation zone and stopping the engines in the centre will scatter the fish. The standard approach is to idle up from downwind or downcurrent, reducing engine noise and wake as you near the buoy. This lets you assess what is present — observing bird activity, surface disturbance, and any visible fish — before committing to a technique.
If fish are visible on the surface, the session often begins with casting. If the area looks active but fish are subdued, starting with a trolling pass around the outside of the aggregation at moderate speed can trigger reaction strikes and reveal what is present. Live-bait rigs suspended at various depths under the FAD are effective when fish are holding deep during the middle of the day.
Trolling: 4–6 knots for tuna and mahi-mahi with skirted lures in 5–10 inch range; 8–12 knots for wahoo with high-speed lures. Always run at least one lure at the surface and one at 5–8 metres depth simultaneously.
Casting: Surface poppers 80–120mm for mahi-mahi and surface-feeding tuna; metal slices 40–80g for mid-water work; small vertical jigs 60–120g if fish are holding deep.
Live bait: Frigate mackerel, small tuna, or any lively baitfish suspended under a balloon or on a controlled-depth rig. This is the highest-percentage method for large yellowfin.
See our trolling techniques Thailand article for detailed rigging and speed guidance.
The Ethics and Legality of FAD Fishing
FAD use globally has attracted significant conservation scrutiny, and for good reason. Industrial purse-seine fishing around FADs captures enormous quantities of juvenile tuna and non-target species (bycatch), causing ecological damage far beyond what is visible at the surface. This is the context in which FAD fishing is controversial.
Recreational sport fishing around existing FADs — approaching a floating structure, catching fish by hook and line, and departing — is a different category of activity entirely. The ecological impact of a recreational fishing charter spending a morning at a FAD is negligible compared to any industrial operation. That said, it is worth being clear-eyed about what FADs represent in the broader context of pelagic fisheries management.
The specific regulatory framework for anchoring new FADs in Thai waters is not straightforward. Commercial operators who deploy and maintain FADs operate under different frameworks than recreational anglers simply fishing around found objects. If you are chartering a vessel specifically for FAD fishing, ask your operator about their FAD-use practices — particularly whether they deploy and maintain their own devices and what licensing framework covers that activity.
For the broader conservation picture on Thai marine fisheries, see our catch-and-release rules Thailand guide and the protected and endangered species reference.
Where and When: Phuket and Khao Lak
The primary FAD-fishing ports on the Andaman side are Phuket and Khao Lak. Both have charter operations that specifically target known FAD locations in the outer Andaman. The typical run to productive FADs from either port is 30 to 90 minutes in calm conditions.
The season runs November through April, aligned with the northeast monsoon and the presence of pelagic species in Andaman waters. December through February is typically the most productive window, with January and February often delivering the most consistent yellowfin action.
The Phuket charter operators overview and Khao Lak charter operators overview both include operators who offer dedicated FAD-fishing day trips. When booking, specify that FAD targeting is your priority — some operators treat FADs as an incidental stop on a broader trolling run, while others make FAD fishing the explicit focus of the day.
Tackle for FAD Fishing
FAD fishing demands versatile gear because conditions at the FAD can change the appropriate technique rapidly.
Main trolling outfits: 30–50lb class stand-up gear with lever-drag reels holding 400m of 30–50lb monofilament or 80lb braid. Two to four rods ready at any time.
Light-tackle spinning: 15–25lb braid on 3000–5000 size spinning reels, 7–8ft medium-heavy rods rated 20–60g. These are your casting rods for surface work and jigging.
Live bait outfits: Heavy enough to stop a large yellowfin on the initial run — 50–80lb class with strong single hooks on a short fluorocarbon trace.
The best time to fish in Thailand guide provides seasonal context across all Andaman destinations if you are planning a broader trip around FAD fishing.
