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Fish

Dusky kob (mulloway, jewfish)

Corvina sudafricana (kob, mulloway)

Argyrosomus japonicus

SaltwaterBrackish

At a glance

Typical size

5–30 lb; 'daga salmon' over 50 lb are true trophies.

Depth

Surf to about 300 ft.

Best time

Night, dawn and dusk; dirty water lets them feed by day.

Found in

7 areas

1

Know it

Spot it, size it up and learn its habits.

Identification

A big, long croaker with a bronze-silver to gray back and silver sides, a large mouth, a row of pale spots along the lateral line in live fish, and a squared-off to slightly rounded tail (pointed in young fish). Very hard to tell from the silver kob by looks alone; the dusky is usually more bronze and is the kob of estuaries and the surf east of Cape Agulhas.

Typical size

5–30 lb; 'daga salmon' over 50 lb are true trophies.

Maximum size

About 6½ ft and about 165 lb (75 kg).

Diet

Fish (mullet, sardines, shad), squid, cuttlefish, prawns and mud prawns.

Behavior

Lives in estuaries, surf zones and nearshore reefs, feeding mainly at night and in dirty water; big kob grunt loudly with their swim bladder. They grow slowly and gather to spawn off the KwaZulu-Natal and Eastern Cape coasts.

2

Find it

Where, when and how deep to look.

Where to find it

Found from Southern Africa, India, Sri Lanka, Maldives & Pakistan, China, Hong Kong & Taiwan, Japan & South Korea, South-East Australia & Tasmania, Queensland & the Great Barrier Reef and Northern Territory & Western Australia. South Africa from the Cape to KwaZulu-Natal and southern Mozambique (big estuaries like the Breede, Kowie, Sundays and St Lucia); also Pakistan and northwest India, China, Korea and Japan, and southern Australia from southern Queensland around to Western Australia, where it's the mulloway or jewfish.

Habitat

South Africa from the Cape to KwaZulu-Natal and southern Mozambique (big estuaries like the Breede, Kowie, Sundays and St Lucia); also Pakistan and northwest India, China, Korea and Japan, and southern Australia from southern Queensland around to Western Australia, where it's the mulloway or jewfish.

Depth

Surf to about 300 ft.

Fishing depth

Deep holes and channels in estuaries, gullies in the surf, and nearshore reefs 30–100 ft.

Best season

Year-round; spring and summer (about September to March) are best in South African estuaries, and big kob follow the sardine run in KwaZulu-Natal in winter.

Best time

Night, dawn and dusk; dirty water lets them feed by day.

Best tides

The top of the tide and the turn are prime in estuaries; in the surf, a pushing tide into gullies.

Best weather / conditions

After a blow when the surf is 'dirty' and discolored; also after rain floods an estuary.

3

Bait & gear

What to tie on and what to throw.

Best bait

Live mullet or shad, whole sardines, squid and chokka, cuttlefish and mud prawn.

Best artificial lures

Soft plastic paddle-tails and jerk shads on heavy jig heads, swimbaits and deep minnows worked slowly.

Tackle setup

Surf: 12–14 ft surf rod and a big reel. Estuary and boat: medium-heavy 7 ft spinning or baitcasting rod.

Hook size

5/0–8/0 circle or J hooks; 2–3 hook snoods for whole sardines.

Line

25–40 lb mono for surf; 30–50 lb braid from boats.

Leader

50–80 lb mono shock leader.

BigJoe's setup for Dusky kob (mulloway, jewfish)

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

Also at Bass Pro Shops: RodReelLineLeaderSinkersHooks

See BigJoe's full gear guide →

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4

Catch it

Step by step, from first cast to landing.

Step-by-step: how to catch it

  1. Go where it lives: South Africa from the Cape to KwaZulu-Natal and southern Mozambique (big estuaries like the Breede, Kowie, Sundays and St Lucia); also Pakistan and northwest India, China, Korea and Japan, and southern Australia from southern Queensland around to Western Australia, where it's the mulloway or jewfish.
  2. Rig up: Surf: 12–14 ft surf rod and a big reel. Estuary and boat: medium-heavy 7 ft spinning or baitcasting rod. 50–80 lb mono shock leader.
  3. Pick your bait: Live mullet or shad, whole sardines, squid and chokka, cuttlefish and mud prawn. Lures: Soft plastic paddle-tails and jerk shads on heavy jig heads, swimbaits and deep minnows worked slowly.
  4. Fish it: Cast a sardine or live mullet into the deepest gully or estuary hole at night, keep the reel's drag light, and wait — big kob often pick the bait up and swim off slowly before you set the hook.
  5. Time it: Night, dawn and dusk; dirty water lets them feed by day. The top of the tide and the turn are prime in estuaries; in the surf, a pushing tide into gullies.
Fishing techniques

Cast a sardine or live mullet into the deepest gully or estuary hole at night, keep the reel's drag light, and wait — big kob often pick the bait up and swim off slowly before you set the hook.

BigJoe's tip

Fish your bait in the 'dirty' discolored water after a southwest blow or a flood — that's when big kob come out to feed in daylight.

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.

5

Clean & cook

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

Edibility

Excellent eating — one of the best-tasting fish in its range.

Cleaning

Bleed and ice it right away. Fillet, then remove the skin and any dark bloodline.

Cooking suggestions

Excellent white, firm meat — fried, grilled, baked or in fish cakes; one of South Africa's favorite eating fish.

6

Stay safe & legal

Safety, rules and taking care of the fishery.

Safety warnings

Night fishing in the surf and on rocks is dangerous — watch the swell, wear a headlamp and never fish alone. Sharks are common in the same gullies.

Regulations

South Africa: from shore and in estuaries east of Cape Agulhas, 1 dusky kob per person per day with a 60 cm (24 in) minimum; boat-based limits differ by area — check the current rules. Australian states set their own mulloway limits. Kob may not be sold by recreational anglers. South Africa requires a recreational fishing permit, with kob limits that change by area and by shore or boat; in Australia (where it's called mulloway or jewfish) each state sets its own license, size and bag rules.

Conservation

Dusky kob stocks in South Africa collapsed to a small fraction of their old size; release the big breeders and keep only what the law allows.

Sources & photo credits

Sources

  1. FishBase — Argyrosomus japonicus
  2. IUCN Red List — Argyrosomus japonicus
  3. International Game Fish Association (IGFA)
  4. FAO Fisheries and Aquaculture
  5. Photo credits