At every night market pier along Thailand's coasts, the squid-fishing scene is the same: LED lights blazing over the water, anglers with simple rods working coloured jigs in a rhythmic up-down motion, plastic buckets filling with catch. Amid the torpedo-shaped squid that most people expect, a different animal occasionally appears on the pier planking — broader, heavier, moving with a distinctive hovering locomotion rather than a squid's darting jet. Pla muk gra-dong. The cuttlefish.
Cuttlefish are cephalopods like their squid and octopus relatives but occupy a distinct ecological niche and exhibit a suite of biological characteristics that make them among the most remarkable animals in any Thai inshore environment. Understanding what makes them different from squid — in biology, behaviour, and fishing tactics — converts a casual bycatch encounter into a deliberate and productive pursuit.
What a Cuttlefish Is
The defining feature of cuttlefish — the cuttlebone — is the internal calcareous structure that gives the animal its distinctive broad, flat silhouette. Unlike the thin, flexible gladius (pen) of squid, the cuttlebone is a rigid, chambered structure composed of aragonite that provides buoyancy control through gas regulation in its internal chambers. The animal can adjust the gas-to-liquid ratio in the bone to achieve neutral buoyancy at different depths — a capability that allows cuttlefish to hover completely motionless in the water column, a behaviour no squid can replicate.
The mantle fins of cuttlefish run as a continuous undulating fringe along the full length of the body, providing precise three-dimensional movement control including perfect sideways, forward, backward, and stationary hovering. This fin system, combined with jet propulsion from the mantle, makes cuttlefish extraordinarily agile hunters capable of positioning precisely relative to their prey before striking.
Thailand's most commonly encountered species are:
Pharaoh cuttlefish (Sepia pharaonis): The largest species in Thai waters, reaching mantles of 40 cm and body weights of 2–3 kg. Distributed on both coasts, found from shallow sandy reef edges to 100 metres depth. A common target of commercial squid/cuttlefish boats operating in the Gulf of Thailand.
Recurve cuttlefish (Sepia recurvirostra): Smaller (mantle to 15 cm, weight to 400 g), common in shallow reef-adjacent areas on the Andaman coast. More likely to be encountered in rocky intertidal zones and by shore-based anglers.
Colour Intelligence
Cuttlefish are famous for their colour-changing ability, which surpasses even the octopus in speed and complexity of pattern generation. A cuttlefish can display rapidly oscillating patterns — clouds, ripples, zebra stripes — across its body simultaneously, using these for camouflage, communication, and hunting. When a cuttlefish approaches prey, it often displays a specific 'hypnotic' pattern of moving stripes that appears to disorient small fish before the strike. Observing this in clear water is one of the most extraordinary sights in Thai shallow marine environments."
Where to Find Cuttlefish in Thailand
Andaman Coast
The Andaman coast's rocky intertidal zones, sandy patch reefs, and seagrass beds provide the habitat diversity that cuttlefish exploit through different seasons and life stages. Key areas include:
Krabi and Ao Nang: The shallow, sandy-bottomed bays adjacent to limestone formations hold pharaoh cuttlefish year-round. Night fishing from the public pier at Ao Nang with standard squid rigs produces cuttlefish alongside squid from November through April.
Trang Province rocky coast: The rocky shoreline between Pak Meng and Hat Chao Mai National Park is productive for shore-based cuttlefish targeting during low spring tides, particularly at dawn. The exposed sandy-rock interface in this area holds recurve cuttlefish in good numbers.
Koh Lanta: The eastern coast of Koh Lanta, facing the sheltered strait between the island and the mainland, has extensive seagrass and sandy-patch habitat. Longboat tours along this coast occasionally encounter cuttlefish at the surface during calm morning periods.
Gulf of Thailand
The Gulf's cuttlefish scene is less celebrated but real. Inner Gulf coastal areas in Chonburi, Rayong, and the upper Gulf coast produce pharaoh cuttlefish from commercial squid boats and occasionally from pier fishing. The waters around the Samui archipelago — particularly the deeper (15–30 m) sandy areas north of Koh Samui — hold pharaoh cuttlefish accessible to boat anglers jigging the mid-depth zone.
Fishing Techniques
Night Squid-Rig Method (Adapted for Cuttlefish)
The standard Thai squid-rig setup — squid EGI jig on a light rod with floating line — works for cuttlefish with two important modifications: slower jig movement and larger jig size.
Cuttlefish are ambush predators that hover and assess a target before striking — they respond poorly to the rapid, aggressive darting of a standard squid retrieve. The productive rhythm for cuttlefish is: cast to depth (or lower vertically), allow the jig to sink slowly to 2–4 metres, then give it a single gentle lift of 30–40 cm, pause for three to five seconds, allow it to sink again slightly, and repeat. The key is the extended pause — cuttlefish will follow a jig for several seconds before committing, and a too-fast retrieve pulls the jig away before the strike.
Light rigs attract baitfish, which attract cuttlefish. A 100–200 watt LED floating light deployed 30 minutes before fishing creates the baitfish concentration that draws cuttlefish into casting range. At well-lit piers, cuttlefish often appear in the lit zone already — look for hovering shapes just beyond the visible baitfish concentration, a metre or two deeper.
Dawn Pier Fishing
Cuttlefish move into shallow water — sometimes less than one metre — at dawn to feed on small fish that have gathered under pier lights overnight. This is a productive window that squid anglers who pack up at midnight miss entirely. A lightweight spinning setup with a 2.5–3.0 size egi fished very slowly at the base of pier pilings and around any submerged structure during the first hour of light produces cuttlefish that have been feeding through the night and are still positioned in shallow water.
Watch for changes in the surface — cuttlefish sometimes produce subtle surface disturbance when hunting very close to the top. A jig cast toward any such disturbance and allowed to sink just two to three metres before a slow retrieve can produce immediate results.
Handline from Rocks
On the Andaman rocky coast, a simple handline with an octopus/cuttlefish jig dropped alongside rock edges at low tide is effective for accessing the recurve cuttlefish that shelter in rock crevices and hunt in the adjacent sandy patches. No rod required — a 3-metre length of 12 lb monofilament, a 3.0 egi jig, and patience are sufficient.
Ink Handling
Cuttlefish ink is more copious and produced more readily than squid ink — a freshly landed cuttlefish that feels threatened will eject a substantial jet that can stain clothing, skin, and tackle permanently. The ink is composed of melanin granules suspended in mucus and binds readily to fabric fibres.
Practical ink management: wear dark or ink-resistant clothing for cuttlefish sessions. Hold the landed cuttlefish at arm's length pointed away from your clothing when it arrives at the surface. A plastic bag positioned to receive the animal as it comes over the gunwale or pier rail allows it to discharge ink into the bag rather than onto you. The ink itself is non-toxic and washes readily from skin — just not from light-coloured synthetic fabrics.
Collecting the ink sac for cooking purposes requires a small sharp knife to carefully separate the silver-grey sac (visible inside the opened mantle) from surrounding tissue without puncturing it. The intact sac can then be dropped into warm water to dissolve, producing the inky liquid used in pasta and stir-fry applications.
Distinguishing From Squid in the Catch
When fishing night squid rigs in Thailand, mixed catches of squid and cuttlefish are common. The distinction matters for cooking, as cuttlefish requires slightly different preparation (the cuttlebone must be removed, while the squid gladius simply peels out):
| Feature | Cuttlefish | Squid | |---------|-----------|-------| | Body shape | Wide, flat, rounded | Torpedo, narrow | | Fins | Full mantle length, undulating | Short, triangular tail fins | | Internal structure | Hard white cuttlebone | Clear, thin gladius (pen) | | Swimming | Hovering, gentle | Darting, jetting | | Ink volume | Large | Moderate |
Cuttlefish skin is also typically rougher to the touch than the smooth mantle of a squid, a difference immediately apparent when handling a fresh catch.
Cuttlefish encountered as bycatch while squid fishing in Thailand are universally keepers for the table. They are considered superior eating to most squid species — the flesh is thicker, more tender, and sweeter — and represent an unexpected bonus in any night-fishing session where their presence might otherwise be unremarked. Paying attention to what comes up on the squid rig is the first step toward targeting them deliberately.
