Cobia
Category: High Risk
COBIA are a species that seem to have a special place in the minds of most anglers who have caught them, and it’s not hard to see why. They are exciting, fascinating and unpredictable. Finding good numbers of decent size cobia is not that common; frequently they are found swimming in small groups and catching one fish is often the end of that piece of cobia action.
Many anglers rate cobia as one of the best fighters in the ocean, generally giving it their all right up until you get a firm hold on them. They can perform extraordinary runs at speed, but are best known and respected for their sheer doggedness. And they are first-class on the plate too. Cobia have also been known at various times and places as black kingfish or crab-eaters – the latter name giving some idea about what constitutes a key part of their diet. These tough and spectacular gamefish are renowned for their habit of swimming in the company of manta rays or large sharks, and the visual presentation of a bait, lure or saltwater fly in these circumstances can be memorable if it results in a strike.
Identification
Many a cobia has been called for a shark during a tussle and that’s not surprising, given their flat, shark-like head and elongate body. With pectoral fins extended they look just like any one of a variety of whalers, especially a bronzie. Cobia up to about 15 kilos carry a distinctive yellowish band along the body, but this tends to disappear in big mature fish. An easy way to confirm you have a cobia is to check out the very short spines on the first dorsal fin.
Size
Cobia grow big in WA waters, with a record fish of 61.5 kilos taken at Shark Bay by Peter Goulding in 1985. Now that’s a big cobia. More commonly, though, anglers catch cobia in the 5-15kg range. Any fish around 20 kilos is notable and 30kg-plus cobia are well and truly of boasting size.
Distribution
Cobia are caught occasionally in Perth waters but the famous high ledges out at Steep Point and rock walls along the rugged Quobba coastline are where they really start to show up. The prolific waters off Dampier and Port Hedland, especially around structures and moorings, also produce plenty of cobia.
Breeding and migration
Cobia are batch spawners and produce huge quantities of eggs. They have been found to produce 370,000 to 1.9 million eggs every four days over a period of several months! They are generally found inside the Continental Shelf and it is thought that they do not make any regular offshore migrations, although they will follow large fish for at least part of their migration routes. Tagging data shows that cobia have travelled only very short distances even after up to 850 days at sea, which indicates that they are not particularly mobile.
Threats
There are no known recreational or commercial threats to this great species.
Tackle and bait
Cobia will take an array of lures – bibbed and bibless minnows, leadhead jigs, soft plastics and certainly surface poppers. Saltwater flies are also deadly in any situation where you can make the most of a close-quarters encounter. Bait works well too, especially an unweighted floating mulie. Given the great fighting ability of cobia I wouldn’t feel comfortable fishing less than 10kg line with a nylon trace of at least 25kg – or perhaps even heavier if the fish are big and anywhere near structure.
Fishing methods
Sight fishing for cobia – typically and famously when they are spotted swimming with manta rays or sharks – is great fun, but take care not to hook the host fish/shark/manta ray! Trolling lures is also productive, though cobia hookups are sometimes in the bycatch category for anglers chasing other species such as mackerel. Trolling baits is less common these days but a well-presented swimming bait may well bring a rewarding cobia strike. These sportfish are legendary for their performance on the end of a line and scary when they go crazy right at the gaff, or at boatside. Cobia are totally unpredictable: some fish hooked from the rocks head 200 metres straight out to sea and stay up near the surface. Others make for the bottom and find a bommie just as surely as would a big yellowtail king. From a boat, a hooked cobia is likely to swim directly to the bottom and stay there, prompting a half-hour tug of war. Some cobia come in meekly, and in short order, and then create mayhem when an unfortunate angler takes a shot with the gaff.
References: Marine Fishes of Northern Australia by Gerry Allen and Roger Swainston. Bluewater Magazine Oct/Nov 2003 by Dr Julian Pepperell. Fishing the Wild West by Ross Cusack and Mike Roennfeldt.