How to tell the sex of a kiwi

GENDER: A kiwi at Rainbow Springs' Kiwi Encounter named Boy, turned out to be a girl. PHOTO/SUPPLIED

Ever wondered how to determine the sex of a kiwi?

The answer is in the feathers, according to Kiwi Encounter husbandry manager Claire Travers.

At Rotorua's Rainbow Springs' Kiwi Encounter hatchery, several feathers from taken from young chicks and sent to Massey University for DNA testing. The DNA material was found at the tip of the feather shaft where it entered the bird's skin.

"We do try to give the kiwi chicks gender-neutral names when they hatch, because we can't determine their sex without DNA testing," Ms Travers said.

"It's only as the birds reach maturity you have a better chance of telling the gender apart, without DNA feather sexing. The female birds are larger, with a longer bill and a very different call to their counterpart."

Rainbow Springs staff tried to make educated guesses but they weren't always right, she said.

"Funnily enough a group of chicks that were named after volunteer workers - Stewart, Stephen and Kevin - all came back as being female. And another chick named Boy turned out to be a female."

Knowing the sex of a kiwi was an important management and monitoring tool, she said.

"We don't want an imbalance of male and female birds in an area.

"Also, male kiwi are tracked when they have reached maturity and have paired as they are the ones who sit on the eggs and incubate them so determining their location is vital.

"This way DoC (Department of Conservation) workers and volunteers can then lift the eggs from the nest and they can be hatched and raised at Rainbow Springs' Kiwi Encounter to a healthy weight in safety before they are released back to the wild, therefore hugely increasing their chance of survival away from stoats and rats," Ms Travers said.

If you want to sponsor a kiwi, visit www.rainbowsprings.co.nz for more details.