A hoard of one of the world's largest insects is about to be released into the wild, to regenerate bush in the Hauraki Gulf.

More than three hundred giant weta - or wētāpunga - will be released tonight in the Noises group of islands - the second lot to be released after the species became extinct everywhere but Little Barrier.

Auckland Zoo ectotherms team leader Don McFarlane says the insects will be the offspring six male and six female weta, to ensure gene diversity.

He says it's almost like a dating service - moving the pairs around to ensure mating success.

Mr McFarlane says the wētāpunga produces one of the largest poo pellets of any insect - so plays a vital role in the ecosystem by germinating and distributing plant seeds.

He says the islands are a paradise for the insect, which is a fussy eater, and says a lot of boxes were ticked before deciding to release the wētāpunga.