Geoff Thomas: Bottom line nabs snapper

This Hauraki Gulf snapper was hooked on a ledger rig while drifting slowly. Photo / Geoff Thomas

When the tide is running strongly, the snapper come on the bite. One theory for this is that the current slices away the top layer of sand or silt, exposing the snapper's food, which is predominantly various types of shellfish and worms.

That is why they favour the rich flats which make up most of the Hauraki Gulf and why it is the predominant snapper fishery in the country; certainly the most consistent. But the same principles apply in other harbours like those at Wellington, Kaipara, Manukau, Whangarei and Tauranga.

The biggest challenge in strong currents is to get the baits to the bottom and keep them there. Often you will see people relaxing in their boats, holding rods and waiting for a bite. It looks very pleasant, but they are not catching fish when they should be. The reason is simple - their baits are not on the bottom.

They have probably got a reel spooled with mono line which is 10kg, 15kg or even heavier, a length of even thicker trace, a big weight and a couple of hooks with large chunks of bait or whole pilchards.

All of this tackle creates huge resistance in the current and, even if it succeeds in connecting with the bottom when first dropped, once the reel is flicked into gear and the line goes tight, the current slowly lifts the terminal stuff up off the bottom.

Even if the snapper can see it, they are unlikely to bite something which is acting so unnaturally. The exception is the precocious small fish which display the aggression needed by the small fry just to survive in a fiercely competitive environment, which is why you hook so many tiddlers.

The solution is to start fishing at slack tide so you get the first hour or so of fishing before the current becomes too strong, and if you want to persist with the tide rip because you are doing so well, you then have to reduce the resistance your tackle has to the current - go down in line weight, not up.

You can increase sinker size until it becomes too unwieldy, which for most rods is 6oz because you can't keep increasing the weight beyond the capability of the line.

Another option is to use braid line, which is so fine it cuts through the current. You can still hit the bottom, or try light 6kg monofilament line.

The other trick is to keep letting out line so your bait slides along the bottom away from you, until it is too far out and you start over again. You can thumb the spool as it runs out at the speed of the current, with the reel set in free-spool, and when you feel a fish start to pull it out, all you have to do is clamp down with your thumb sharply, flick it into gear and wind until the weight comes on. It can be quite a performance, but it works.

Too little current creates different challenges. You can reduce the size of your sinker - and the rule of thumb is to always use only as much weight as is needed - and use baits which create movement, like squid tentacles.

The key is to have moving baits. It helps to be proactive; in other words, if sitting waiting for a bite, move the rod up and down slowly to impart some "life" into the bait at the other end. Or, if fishing in a strong current, you can wind in some line, let it out again, and so on.

Another way of achieving this is to drift and it's better during the week when there are not so many other boats around. Do it in the weekend and you'll soon be bouncing off a lot of unhappy boaties. Or go out into the wide open spaces and try it.

This also works well in the Rangitoto Channel - the only thing you have to watch out for is a patch of rocky bottom where you can become fouled. Keeping an eye on the depth sounder will help here.