Saltwater · Summer peak in inner bays and estuaries; fish are present from late spring into autumn

Bartail Flathead

Platycephalus indicus

With the olive flounder, this is one of Japan's two 'summer flatfish' — but the flathead is no flatfish at all: it is a crocodile-headed ambush predator that buries itself in sand and mud and erupts at passing prey. Bay anglers work soft plastics slowly along the bottom for it all summer, and its firm white flesh is a prized summer sashimi.

Seasons · Peak

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Bartail Flathead — Photo: Hamid Badar Osmany, CC BY 3.0 — Wikimedia Commons

Identifying features

Broad, strongly flattened crocodile-like head with eyes on top
Very wide mouth reaching back under the eyes, with small sharp teeth
Mottled brown and tan camouflage over the back and head
Bony ridges and spines on the head — handle with care
Tail fin with several dark horizontal bars, the mark behind the name 'bartail'

Habits

Lies buried in sand or mud with only the eyes showing, waiting in ambush
Bursts upward to grab small fish, shrimp and crabs passing overhead
Most active in the warm months in shallow bays and estuaries
Hunts mainly around dawn, dusk and tide changes
Often lies on the edges of channels and drop-offs where prey is carried past

Distribution

Regional coverage expanding

Where to find them

Tokyo Bay estuaries and river mouths, Chiba side
Mikawa Bay tidal flats, Aichi
Sandy bays of the Seto Inland Sea

Where they live

Sandy-mud bottom in inner bays and estuariesTidal flats and river mouthsSandy edges of channels in about 10-60 ft (3-20 m)

How to catch them

Soft plastics along the bottom from shore Shore

Rig: Light lure rod casting a jig head with a soft-plastic grub or shad tail from bay shores and river mouths, retrieved slowly just above the bottom

Bait/lure: Soft-plastic grub or shad tail in natural colours

Key tip: Let the lure sink to the bottom after each short lift — flathead strike as it falls or sits on the sand.

Bottom lure fishing from a bay boat Boat

Rig: Boat lure rod working a jig head and soft plastic, or a small metal jig, vertically and on short casts over sandy-mud bottom

Bait/lure: Soft-plastic shad tail or small metal jig

Key tip: Keep contact with the bottom and pause often; a buried flathead will not chase a lure that stays high.

Best baits & lures

Soft-plastic grubs and shad tailsLive shrimpSmall baitfish such as silversides

Techniques for Bartail Flathead →

Baseline setup

Rod: Light lure rod 7-8 ft (2.1-2.4 m)
Line: 10-16 lb braid with a 12-20 lb fluorocarbon leader
Terminal: Jig heads 1/4-3/4 oz, soft plastics, small metal jigs

Recommended gear for this species

Rod · Best value

9' 5-weight fly rod outfit

≈ US$180-260

Covers chironomid lakes and small rivers with one setup.

Flies · Budget

Chironomid assortment (30 patterns)

≈ US$25-40

Chironomids are 60% of a lake rainbow's diet in spring.

Picks come from our rule library — never paid placements. Prices are guides; affiliate links may earn us a commission.

Typical size

Common 12-20 in (30-50 cm); large fish to about 39 in (100 cm)

On the table

Excellent — firm, translucent white flesh prized as summer sashimi; also good in soups and fried.

Similar species

Olive FlounderThe olive flounder is a true flatfish with both eyes on one side of an oval body; the flathead is flattened top-to-bottom with a crocodile head and eyes on top

Regulations vary by area and can change in-season — always check the official rules for your area before you fish. Regulations guide →

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