The Department of Conservation (DOC) says kākāpō could breed in record numbers this year, with mating season off to an early start.

Photo: Jake Osborne

There are just 147 of the native birds left but that number could increase by 40 by midway through the year.

DOC scientist Dr Andrew Digby said a lot of work was being done to monitor and protect the species and boost their numbers.

His team of specialists were working across three predator-free breeding islands and fitting kākāpō with trackers - with which they have recorded birds mating "unexpectedly early".

Photo: Supplied / DOC

He said it was extremely hard to know how many chicks will be born, but the team were optimistic it could be above the 2016 record of 34.

"One of the biggest threats to kākāpō is actually infertility. About half of eggs that are laid are infertile and a third of eggs that are laid turn into chicks," he said.

Dr Digby said unfortunately, one male kākāpō was also found dead on Anchor Island on the weekend, likely killed in a fight with another bird.

But he said it was an exciting time for the species, who did not breed often.

"This is why we do kākāpō conservation, these big years. It will hopefully be our biggest season that we've ever had, so it will be really exciting to see just how big the kākāpō population is come June-time."

The next issue, he said, could be finding enough space for all the new birds to live.

"It is a good problem to have, too many kākāpō for the habitat. But it points to the longer term problem that we need more space for them."

He urged New Zealanders to support pest-control initiatives and efforts, which benefited all types of native birds.

"It's not just kākāpō. Most species like kiwi, takahē, have this same problem of trying to find suitable, predator-free habitat," he said.

On a more kākāpō-specific scale he said people could make donations to the kākāpō program through DOC.

"Also just spreading the word, telling people about these amazing birds that exist in New Zealand, and raising awareness of them."