The zoo's curator of ectotherms and birds, Richard Gibson, said new techniques involving rearing the insects in groups as well as individually, were trialled within the zoo's temperature controlled weta facility for the first time.
"It's been a pretty intense period of work for the team, but an absolute privilege to be helping such an iconic threatened species.
"We're delighted to have achieved a 95 per cent success rate in rearing animals individually, and around 50 per cent success rate with the groups - significantly higher than we expected."
The 150 weta released today are close to adulthood, and it is expected they will soon begin to breed.