Pukaha Mount Bruce National Wildlife Centre in the Wairarapa is celebrating the hatch of its 100th kiwi chick since it started raising kiwi using the Operation Nest Egg technique in 2005.

Conservation manager Todd Jenkinson was thrilled to announce today that a healthy, North Island brown kiwi chick had hatched - marking a significant milestone for Pukaha.

Todd and lead kiwi ranger Jess Flamy went into the Pukaha reserve on March 16 to retrieve two eggs from Kakama, a monitored male who lives in the wild.

The duo expected the two eggs to hatch over the next three weeks but were surprised to discover one egg had already started hatching. The first egg hatched on Saturday while the second egg is expected to hatch in a few weeks.

"The egg had externally pipped, which is when the kiwi has broken through the shell, starting the full hatch process. We brought it in from the reserve and along with a second egg put them both straight into the brooder", says Todd. "After that it took one more day for the first one to fully hatch."

Todd said being the 100th kiwi chick to hatch under Operation Nest Egg was significant.

"Operation Nest Egg is a process where eggs are retrieved from the wild and the kiwi hatch in protected areas with the assistance of trained staff. The survival rate of these kiwi is 65 per cent compared to five per cent if they hatch in the wild, so for us to have our 100th chick hatch here since September 2005 is something to be celebrated."

Pukaha Mount Bruce will celebrate the milestone with a Kids Go Free day on Sunday, March 26 where the 100th kiwi chick will be on display briefly at midday.

Pukaha general manager Helen Tickner says it will be a great way to thank everyone in the community who has supported the centre over the years.

"We're rapt that we've reached this milestone but we know it wouldn't have been possible without the long term support and assistance of all our supporters. We really want to share this unique and special occasion with everyone."