There's excitement at the National Zoo in the US, over the first chick hatched to what were the first Kiwi to leave New Zealand in two decades.

The chick hatched last month but has only just started eating for itself.

Its parents, Ngati Hine Rua and Ngati Hine Tahi, were gifted by New Zealand in 2010.

Warren Lynch, a biologist at the Smithsonian National Zoological Park in Washington DC, said it's taken six years to get to this point.

"We're very thrilled to finally be able to produce offspring from this pair which is actually designated as the most genetically valuable pair found outside of New Zealand in the world. So yeah this is a very big deal.

"They're genetically significant because they are new genetic stock that came out of New Zealand. Their genes are very valuable to the population outside of New Zealand."

Feathers from the new chick will be sent back to New Zealand, once it's old enough.

"Any feathers that are moulted are collected daily by the keepers," Mr Lynch said. "They place them in bags and then once we have large enough bulks, those feathers are shipped back to New Zealand where they are presented to Maori."