Geoff Thomas: Silver fighter wasted as bait

The giant trevally is the Jurassic Park version of our silver trevally. Photo / Geoff Thomas

Sometimes when you are snapper fishing you hook a fish that has got to be the biggest snapper you have seen all day.

It pulls twice as hard as any other you have caught, but when you finally see a glint of silver it turns out to be a trevally. Then, just as you lift it out of the water the hook pulls out and your fish drops back into the sea and disappears in a flash. It was in fact a silver trevally and, while it was the same size as pannie snapper, it put up a real scrap on the rod.

Our trevally is one of a family of trevallies found around the world and, a generation ago, it was regarded as being only good for bait. For many years that was the only bait you could buy - blue cardboard packets of frozen trevally fillets. And it caught fish. A lot of fish. Although there were far more fish around in those days, and I hate to think how many we would have slaughtered as youngsters if we had access to pilchards, or the white Californian squid or bonito or soft baits.

Trevally is still a good bait. Big snapper love a whole trevally with one fillet sliced off, and small fish will grab strips dropped on a ledger rig. But they are too good to be consigned to the bait box.

Those who relish chilled portions of translucent flesh delicately dipped on soy sauce and green wasabi paste, rate trevally at the top of the list. There is nothing wrong with fillets poached in milk, or a fat trevally fresh from the smokehouse with the flesh picked from the skin while still warm and dripping with juices.

Most trevally are caught by accident while fishing for other species. They will take a bait, a silver jig or a soft plastic lure. But they can be targeted, particularly in spring when they move inshore to spawn.

The trick is to use clear fluorescent leader as thick line and heavy hooks will deter them, and drop down in hook size so the hook can be hidden in the bait with just the point protruding. A size 4/0 or 3/0 in thin gauge steel is ideal, and recurve hooks ensure contact in the corner of the jaw. With no teeth, our trevs eat soft foods, so small baits of shellfish such as mussel or tuatua work well, but must be secured with bait cotton. They will also take small chunks of pilchard or bonito, and the bait should drift in the current.

Berley will attract the silver beauties and fishing along the edge of a bed of thick weed where it meets the sand is always a good starting point.

When hooked, trevally will test the tackle and the angler's skill with the rod, as their deep flanks use the current to deliver maximum power. A rod with plenty of give in the tip and power in the butt, and a reel with a good drag system is needed. Keep away from cheap, department-store outfits.

The trevally which haunt offshore islands such as White Island, Great Barrier and the Three Kings are mega-models, pushing the scales to 9kg or more, and will test the strongest tackle. But they are still minnows when compared with the giant trevally of the Indo-Pacific oceans. The famed GT is basically a Jurassic Park version of our trevally, and is a fearsome hunter of small fish and other prey. They grow to 100kg but such monsters are impossible to stop on a rod and line - they are just too powerful and, as they live near reefs, they get into the coral and that's the end of the argument. The world record is a fish of 72.8kg (160lb 7oz) caught in Japan in 2006.

In Hawaii, it is called ulua, and the local method of subduing them involves a live bait set at night from the shore on a line of stout rope which is tethered to the ground and run over the branch of a tree so when a fish is hooked the branch provides a spring to absorb the pressure - not sporting, but effective.

The local fishing paper once reported an ulua of 136kg (300lb) caught in this manner.

The usual method of fishing for GTs around the Pacific islands involves casting surface poppers which is very visual, and exciting when the sea opens up and a fish like a table grabs your popper. They will exploit any weakness in the tackle, leaving the angler with a racing heart and sweating brow.

Like old man snapper, such monsters are coarse in the flesh and are best released to fight another day. But when it comes to sashimi, our humble silver trevally are hard to beat.