Fish

Dusky grouper

Mero (mero común)

Epinephelus marginatus

Saltwater

At a glance

Typical size

5–40 lb.

Depth

15–600 ft; big fish mostly deeper than 100 ft outside reserves.

Best time

Dawn and dusk.

Found in

9 areas

Spot it, size it up and learn its habits.

Identification: A huge, heavy grouper with a big mouth, dark reddish-brown to gray-brown body covered in irregular pale blotches, a pale-edged tail and fins, and often a golden-yellow belly.
Typical size: 5–40 lb.
Maximum size: About 5 ft and over 100 lb.
Diet: Octopus, squid, crabs and fish.
Behavior: A slow-growing, long-lived grouper (50+ years) that lives in rock caves and is very territorial. All start as females and the big ones become males. In protected reserves they become tame around divers.

Where, when and how deep to look.

Where to find it: Found from Spain & Portugal (Azores, Madeira & Canaries), France, Italy & Malta, Greece & the Adriatic, Turkey, Cyprus & the Eastern Mediterranean, Morocco & West Africa, Southern Africa, Southeast Brazil and Southern Brazil, Uruguay & Argentina. Rocky reefs with caves and crevices through the Mediterranean, along the Atlantic coast from Portugal to South Africa, and off southern Brazil.
Habitat: Rocky reefs with caves and crevices through the Mediterranean, along the Atlantic coast from Portugal to South Africa, and off southern Brazil.
Depth: 15–600 ft; big fish mostly deeper than 100 ft outside reserves.
Fishing depth: Tight to the bottom at its cave.
Best season: Most active in summer.
Best time: Dawn and dusk.
Best tides: Little tide in the Mediterranean.
Best weather / conditions: Calm days.

What to tie on and what to throw.

Best bait: Live octopus, squid and fish where fishing for it is still allowed.
Best artificial lures: Heavy jigs and big soft lures (often caught by accident while jigging for dentex).
Tackle setup: Heavy jigging or bottom rod with a 30–50 lb class reel.
Hook size: 5/0–8/0 circle hooks.
Line: 50–80 lb braid.
Leader: 80–100 lb fluorocarbon.

The rod, reel, line and lures BigJoe would use.

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Step by step, from first cast to landing.

Go where it lives: Rocky reefs with caves and crevices through the Mediterranean, along the Atlantic coast from Portugal to South Africa, and off southern Brazil.
Rig up: Heavy jigging or bottom rod with a 30–50 lb class reel. 80–100 lb fluorocarbon.
Pick your bait: Live octopus, squid and fish where fishing for it is still allowed. Lures: Heavy jigs and big soft lures (often caught by accident while jigging for dentex).
Fish it: Not a target fish in most of its European range. If one is hooked by accident, keep it coming up fast to keep it out of its cave, and release it with a descending device so it can get back down.
Time it: Dawn and dusk. Little tide in the Mediterranean.

Fishing techniques: Not a target fish in most of its European range. If one is hooked by accident, keep it coming up fast to keep it out of its cave, and release it with a descending device so it can get back down.
BigJoe's tip: See them in marine reserves like Medes (Spain), Port-Cros (France) or Lavezzi (Corsica) while snorkeling or diving; they are a sign of a healthy reef.
Catch and release: Catch and release: wet your hands, keep the fish in the water when you can, and release it quickly. Use circle hooks and a dehooker.

Is it good to eat, and how to prepare it.

Safety, rules and taking care of the fishery.

Safety warnings: Big fish with strong jaws and sharp gill covers; fish caught deep suffer from swim bladder swelling — use a descending device.
Regulations: Listed as Vulnerable by the IUCN. France has banned taking groupers in the Mediterranean (including Corsica) for decades, with the ban renewed for another ten years in 2023; Spain, Italy, Malta, Croatia and Turkey protect it with marine reserves, size limits or bans that vary by region. In many places it is release-only. Check the local rules. Sea fishing rules change by country: the UK, Ireland and France need no sea license, Spain, Portugal, Croatia and Greece sell or require recreational sea licenses or permits, and Italy asks for a free online registration. All have minimum sizes, and marine reserves have no-fishing zones.
Conservation: Dusky grouper were wiped out by spearfishing in many areas and are only coming back thanks to protection. Let them go.

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Sources & photo credits