Harvey Clark: Elusive, expensive, and delicious

The season to catch the most expensive fish on the market - those slimy, translucent, wriggling little black-eyed worms more acceptably known as whitebait - begins at 5am on Tuesday, but don't any expect good catches right away.

Storms and floods around the North Island have left rivers high and murky, especially in the tidal reaches where most whitebaiting is done. Netting is difficult in such conditions and shoals cannot easily be spotted.

However, the runs of whitebait up rivers and streams from the sea are often triggered by increased flows, and catches should improve next week if the weather is fine and the water clear (although the long-range forecast holds little promise).

For the past couple of years the first fresh whitebait on the market in Auckland from the prime West Coast fishery in the South Island have been knocking on $100/kg. If the early-season catches are down, you can bet next week's prices will beat that.

Auckland's main fishery is the lower Waikato River, and ranger Merrin Whatley will be out checking and if necessary enforcing the regulations. "We'll be looking mainly for people leaving nets unattended - you must remain within 10m of your net at all times - or using bigger nets than allowed. Sometimes they have too much net out there."

The New Zealand whitebait spends half its life growing to adult size in freshwater streams. In autumn the adult migrates toward the sea and, in the lower reaches of a river, lays its eggs on the riverbank grasses and reeds that become flooded by the tide. During the next spring tide the eggs hatch into larvae which are flushed down to the sea, where they form part of the ocean's plankton mass. Six months later the developed juvenile returns to its river in the spring and moves upstream to live.

The short life of a whitebait is a constant battle. This tiny fish faces storms and floods, ocean predators such as kahawai, diving seagulls and cormorants and, when it returns to the river, voracious trout and hungry humans with nets, culverts and dams that block migration and prevent spawning, pollution caused by development, farm run-off and streamside bush clearance, cows tramping over their breeding areas and now, it has been learned, mice.

Mice have been sneaking out at night and munching whitebait eggs: riverside caviar. They've been caught red-handed on film. Niwa scientists set up video cameras at two breeding sites on the lower Mokau River in Taranaki to try to find what was preying on whitebait eggs. Mice came out and gobbled the eggs at both sites. A mud crab had its share, too.

Meanwhile, if you want to go whitebaiting, you can get a net from W.S. Laurie fishing specialists down at the waterfront.

For $69 you can buy the popular, basic hoop net that breaks down into two pieces for easy storage. A top-of-the-range model costs $219 but for the really serious a Southland set net, which has a long trailing sock behind a square mouth, will set you back $350.

No licence or permit is required to go whitebaiting.

In the old days, kids caught whitebait for pocket money. As boys in Southland, we would throw away the whitebait we caught in our trout-bait nets.

A relative used to mix up a basinful of whitebait with an egg, a sprinkle of salt and pepper, and pour the lot into a large shallow frying pan: whitebait cake! Now beat that.