New mum Jan gave birth three weeks ago, bringing the number of spider monkeys at the Nulkaba park to six.

The baby's sex is not yet known, as it has been clinging to its mother and staff have remained 'hands-off', zookeeper Chad Staples said.

Mr Staples said the team will decide upon a name for the baby once its personality starts to come through.

Spider monkeys are of South American origin, reach maturity around five-to-six years old, and live well into their twenties.

Mr Staples said the other female spider monkeys have been spending a lot of time around the new mum and baby.

"They're a lovely family group... the other girls have taken a lot of interest, sitting with the mother and trying to encourage her to let them hold the baby, watching and learning for when it's their turn," he said.

Mr Staples said it has been a busy month at the wildlife park, with great weather over the Easter long weekend.

The park has free entry for kids (with the purchase of an adult ticket) throughout April. Visit huntervalleyzoo.com.au for bookings.

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