KEY POINTS:
Water temperatures have cooled significantly in the past week and the fishing is changing accordingly.
Annually at this time of the year the change is most obvious on the Manukau Harbour. Snapper fishing drops dead, while gurnard fishing picks up spectacularly.
The gurnard fishing off the east and west coasts has improved dramatically in recent years. They are now a regular off Auckland's east coast, in the Bay of Islands and off the Far North coast, where just a few years ago catching "grunters" was rare.
The Ministry of Fisheries puts this down to two factors: gurnard are a lightly-exploited fish commercially and there have been several seasons of good recruitment from larval stage.
The Total Allowable Commercial Catch is 4993 tonnes nationally, of which 3589 tonnes was taken in 2006. In the GUR1 area, which covers the north of the North Island, TACC is 2287 tonnes but this varies between 900-1330 tonnes a year.
Mostly it is taken as by-catch from other trawl fisheries, commonly snapper or trevally. Because the fish are generally under 1.5kg they offer lower returns than larger species. They are harder to process, hence they are often sold as "skin on".
Gurnard have a long spawning period from spring through to late summer and the spawning grounds are widespread across the inner continental shelf. Eggs and larvae develop on the surface. The fish start feeding at just over one week's age and grow rapidly, to 23cm within two years. Then growth slows but they mature by age three, at the recently introduced legal size limit of 25cm.
Over winter, gurnard move into harbours and on to inshore mudflats to feed on crabs, crustaceans, baby flounder and shrimps. They are an easy catch and well worth targeting - shop-bought gurnard doesn't even come close to fresh-caught for taste.
The recreational catch is estimated at 400 tonnes nationally, around 200 tonnes in GUR1.
That will be rising significantly but the scientists say the stocks are well above BMSY, the Maximum Sustainable Yield required to sustain the biomass.
On the Manukau, we use Black Magic terakihi flasher rigs baited with small strips of squid, fresh kahawai or mullet, or salted bonito or pilchard. The three-hook rigs will frequently produce three gurnard. If you get one on the line, leaving it down for a few minutes will often attract more.
The best fishing is on the edges of the sand banks as the tide drops, when the fish are moving from the flats to concentrate back in the channels. Slack tide high and low is usually slow.
Anglers have been catching snapper and gurnard on soft baits while at anchor, generally just after tide turn and with berley working. Use shellfish berley rather than fish mash so as to avoid attracting sharks.
Mussel, pipi or tuatua baits tied with bait elastic will pull trevally.
The secret on the Manukau, as usual, is to use light line of small diameter that does not "thrumm" in the current and send out off-putting vibrations to the fish. Nothing heavier than 3kg mono or 4kg braid is necessary as the catch will not usually exceed those weights and in general there is nothing for hooked fish to run for and cut you off on over the Manukau's sand banks.
On the east coast, snapper fishing is also on the change, with good catches still reported right in close, including the upper Waitemata Harbour, Firth of Thames and Northland coast but it is patchier than a month ago. The snapper will soon head for deeper waters as baitfish schools decline. Already, the best fishing out of Auckland is at the 40-metre mark, where fish from 3-7kg are still in large schools under gannet work-ups.
Charter operator Alan Viscovich on Cobalt said the fish north towards Tiritiri Matangi are generally bigger than those at the bottom end of Waiheke. "Most baits are working - squid seems to be working best."
The encouraging thing this summer has been the number of large kahawai out of Auckland and right up to the Far North, including the Bay of Islands and Doubtless Bay.
