Gemfish
Gemfish turn up as a bonus — or a nuisance — when you're dropping baits for hapuku or bluenose in deep water off the North Island.
They school hard, hit baits without hesitation, and run 2–5 kg on average with fish pushing close to 10 kg around places like Mayor Island. The flesh is white, delicate, and excellent smoked — better eating than their snake-like appearance suggests.
Scientific Name: Rexea solandri
Also known as Silver Kingfish, Southern Kingfish, mākakaraki
- Long, slender, compressed body with iridescent silver flanks shading to pale white on the belly; back and head carry a distinct blue tone.
- Dark stripe along the back and a black blotch on the membrane between the first three dorsal spines — a reliable ID mark that separates them from barracouta.
- Deeper-bodied than barracouta, with large, dagger-like teeth on both jaws — handle with care, dead or alive.
- Average 60–90 cm and 2–5 kg; fish over a metre and close to 10 kg are caught around Mayor Island; maximum recorded around 135 cm.
What to know
Habitat Distribution
- Found throughout New Zealand on the continental shelf and slope, from about 50 m down to 550–600 m depth.
- Most fishing effort is concentrated off the northern and eastern coasts of the North Island; Mayor Island is a well-known recreational spot.
- A schooling, mid-water to near-bottom species — adults hug the seafloor but move into midwater at times; juveniles are pelagic.
- Spawning migrations bring fish shallower during winter months, making them more accessible to both recreational and commercial fishers from around February through July.
Key Locations
- Mayor Island (Tūhua), Bay of Plenty — a well-known recreational spot where fish to nearly 10 kg are regularly caught.
- Northern and eastern coasts of the North Island — where the main target fisheries are concentrated, including commercial and recreational effort.
- North Cape area — thought to be a key spawning ground, with fish accessible in shallower water during winter.
- North of the South Island — another spawning area, with fish moving shallower during late winter.
Specific Spots
- Work baits close to the bottom on the continental slope — gemfish school near the seabed but will rise into midwater, so a bait fished just off bottom covers both zones.
- During winter spawning migrations, fish move shallower along the slope; targeting the upper edge of the drop-off (50–200 m) can intercept these schools.
- Around seamounts and offshore pinnacles like Mayor Island, fish concentrate where baitfish and squid gather — the same structure that holds hapuku and bluenose.
Gemfish FAQ
Answers from onWater's species guide.
What are the best lures and bait for Gemfish?
Whole or cut squid is the go-to bait, it matches their natural diet and holds on the hook at depth. Fresh fish baits (cut mackerel, pilchard) also work well. Large jigs and knife jigs worked near the bottom will take gemfish, especially when schools are active in midwater during winter migrations.
When is the best time to fish for Gemfish?
Catchable year-round, but winter (June–August) is peak season as spawning migrations bring schools shallower and concentrate fish along the slope. Commercial peak runs February through July; recreational fishing follows the same pattern, with the best action typically from late autumn through winter.
How do you catch Gemfish?
Most recreational anglers encounter gemfish while bottom fishing for hapuku or bluenose from boats over deep-water structure and the continental slope. Dropping squid or fish baits to the bottom on multi-hook rigs in 100–400 m of water is the standard approach, with electric reels making the deep retrieves practical.
What do Gemfish eat?
Feeds on squid, lanternfish, dories, and rattails, mid-water and bottom-dwelling prey. Large whole or cut squid and fish baits work well because they match what gemfish are already hunting at depth.
Where do Gemfish live?
Found throughout New Zealand on the continental shelf and slope, from about 50 m down to 550–600 m depth. Most fishing effort is concentrated off the northern and eastern coasts of the North Island; Mayor Island is a well-known recreational spot.
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