Saltwater · Year-round on deep reefs; summer spawning aggregations form off some coasts
Marble Grouper
Dermatolepis inermis
A handsome black grouper painted with big white blotches, hiding in caves on deep rocky ledges; it is one of the rarest groupers in sport catches and is listed by IUCN as Data Deficient (2018).
Seasons · Peak
Identifying features
- Black to dark brown body and fins covered with many large white to silvery blotches
- Deeply compressed body with smooth cycloid scales
- Very large rounded pectoral fin with a fleshy scaly flap
- Second anal-fin ray longest — a trait unique in the family
- Young more mottled grey, white and black
Habits
- Solitary and secretive-shy, spending the day hidden in caves and deep crevices
- Emerges along ledges to feed on reef fishes
- Forms spawning aggregations of up to about 200 fish off Brazil in summer
- Rarely seen in fish markets; vulnerable to fishing pressure
Distribution
Where to find them
- Deep ledges and cave-pocked rock at 30-100 m
- Shelf-edge reef drop-offs
- Rocky bottom beside deep reef walls
Where they live
How to catch them
Live-bait bottom fishing on deep ledges Boat
Rig: Heavy conventional tackle, 80 lb braid, fish-finder rig with 8/0-10/0 circle hook and 80-100 lb leader
Bait/lure: Live pinfish, grunts or sardines
Key tip: Present baits beside ledge caves and rock piles at 30-100 m; these shy fish rarely chase — patience and a still bait win strikes.
Deep jigging on ledges Boat
Rig: Heavy jigging rod, 7-9 oz vertical jig on 80 lb braid with a long fluorocarbon leader
Bait/lure: Vertical jig (lure)
Key tip: Work jigs tight to the ledge face and rock structure; deep groupers hit on the fall or the first lifts off bottom.
Best baits & lures
Baseline setup
- Rod: Heavy conventional bottom rod or jigging rod
- Line: 80 lb braid with 80-100 lb leader
- Terminal: 8/0-10/0 circle hooks, 8-16 oz sinkers, vertical jigs 7-9 oz
Recommended gear for this species
Rod · Best value
7'6" medium-heavy jigging rod
≈ US$110-170
Works 2-6 oz jigs over rock and reef and still has the backbone to lift a halibut off the bottom.
Line · Budget
50 lb braid with 40 lb leader (200 yd)
≈ US$25-40
Thin braid cuts the current so jigs stay vertical; the leader shrugs off rock and teeth.
Terminal · Budget
Leadhead jigs, swimbaits and two-hook bottom rigs
≈ US$25-40
A leadhead with a swimbait tail is the universal bottom-fish catcher, from rockfish to cod to flounder.
Picks are never paid placements. Prices are guides; price links are coming soon and none is an affiliate link yet.
Typical size
Maximum 91 cm TL and 10 kg
On the table
Rarely eaten simply because it is rarely caught; deep-reef grouper — check local rules and consider release given its rarity.
Similar species
Misty GrouperMisty grouper is brown with 8-9 regular dark bars and a cheek streak, living deeper (100-400 m); marble grouper is black with white blotches and no bars
Black GrouperBlack grouper shows rectangular dark saddle blotches in rows on a lighter body; marble grouper is near-black with big round white spotsRegulations 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 Marble Grouper
Build today's plan⚠ Heads-up: Marble Grouper doesn't occur around Vancouver, BC (or is very rare there), so it's not a sensible local target. Your plan stays in Vancouver, BC and is built around the fish that actually live there.