Saltwater · Year-round in Hawaiʻi; best May to September over warm reefs
Bluefin Trevally
Caranx melampygus
Known in Hawaiʻi as ʻōmilu, the bluefin trevally is the everyday whipping target of Hawaiian reef angling — a smaller, electric-blue cousin of the giant trevally. Juveniles roam inshore sand and reef flats, while adults patrol reef edges and channels hunting fish, squid and crustaceans.
Seasons · Peak
Identifying features
- Electric-blue anal, dorsal and tail fins — unmistakable in the water
- Dense black speckles scattered over the back and sides, increasing with age
- Silvery to brassy body with a steep, blunt forehead
- Juveniles are yellowish with blue fins and few or no speckles
- Deeply forked tail on a thick, powerful jack body
Habits
- Patrols reef edges and channels, charging baitfish schools
- Juveniles feed inshore over sand and shallow reef; adults hold deeper structure
- A top target of Hawaiian 'whipping' — casting and retrieving lures along reefs
- Feeds mainly by day on small fish, squid and crustaceans
- Often hunts in small packs and follows larger predators for scraps
Distribution
Where to find them
- Reef edges off Oʻahu, Maui and the Big Island at dawn and dusk
- Channels and harbour mouths with strong tidal flow
- Rocky points and surf breaks along exposed Hawaiian coasts
Where they live
How to catch them
Whipping reef edges Boat
Rig: 7-8 ft medium spinning rod, 20-30 lb braid, casting plugs, spoons or flies worked fast along reef edges and drop-offs
Bait/lure: Plugs, metal spoons, streamer flies
Key tip: Cast up-current and retrieve steadily — ʻōmilu slash at moving lures and rarely take a dead-still one.
Live bait and dunking Rock fishing
Rig: Medium spinning or conventional outfit, live bait on a circle hook dunked near channels, points and reef ledges, with or without a small lead
Bait/lure: Live pilchards, small reef fish, shrimp
Key tip: Fish moving water at dawn and dusk; let the bait swim naturally and expect a hard first run.
Best baits & lures
Baseline setup
- Rod: Medium 7-8 ft spinning rod
- Line: 20-30 lb braid with 30-40 lb leader
- Terminal: Casting plugs, spoons, circle hooks and small leads
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 2-6 lb (0.9-2.7 kg); large fish to about 20 lb (9 kg)
On the table
Good — firm white flesh; very large reef fish can carry ciguatera, so release the giants.
Similar species
Giant TrevallyGiant trevally grows far larger and lacks the electric-blue fins and dense black speckles; the bluefin stays smaller and brighter
Crevalle JackCrevalle jack is an Atlantic and Gulf fish with a dark opercle spot and plain fins — no blue colour or speckles, and it does not occur in HawaiʻiRegulations vary by area and can change in-season — always check the official rules for your area before you fish. Regulations guide →
Plan a trip for Bluefin Trevally
Build today's plan