The fact that all of our rarest fish have a whitebait stage in their life cycle is the reason I could never eat whitebait or support the catching of it for food - the giant kokopu might only make up around 1% of the run - but considering how many whitebate EACH person who catches them pull out of the ecosystem each year - I'm sure you'll agree that numbers wise that is allot of the rare fish being eaten - before they even get a chance to grow up!! I don't see how people can justify eating baby fish - It makes absolutely no sense eating any animal before it gets a chance to reproduce. And as we have destroyed most of our native fishes habitat as well as constantly introducing trout that eat them, I don't understand how anyone who loves our country and wants to let the next generation enjoy it too can kill SO MANY of its native animals at one time! Just because fish don't sing like a tui doesn't mean they aren't important!!
Ok - rant over

may be why there is a set time each year that you are able to catch them.
the amount we catch is quite small compared to what comes up our rivers.