Despite kowhai in full bloom, Wellington kereru are nowhere to be seen

It's September in Wellington and the much-loved kereru, the native and endemic pigeon with contrasting green and white plumage, has yet to be spotted.

That's no overstatement.

There are literally no kereru to be seen.

"This time of year we should see heaps of them everywhere," Barrett Pistoll, a senior environmental monitoring officer at Greater Wellington Regional Council, told AAP.

"We've had lots of members of the public ringing up, saying 'where are these birds?'"

Driven by nearby sanctuary Zealandia, Wellington has defied global trends and enjoyed a return of endemic birds to populated areas in significant numbers over the last decade.

But this year, the kereru are late.

A council tally over the last month in nearby Kaitoke Regional Park, which has averaged 150 daily sightings over the last five years, produced no sightings.

Adding to the mystery, the kereru's favourite food - the bright yellow flowers of the kowhai trees - have blossomed around the capital.

So where are they?

"The theory is that they're still feeding in the forest," Mr Pistoll said.

"In the summer we experienced a mast, an episodic fruiting event of large proportions.

"That fills the forest with food for birds. So our working theory is there's so much food left in the forest the birds are hanging out in there and haven't bothered coming down."

People are so full of affection for the kereru it won the title of 2018 Bird of the Year in a national popular vote.

Its absence from populated areas could affect another Kiwi tradition; the Great Kereru Count.

New Zealanders are asked to take part in the country's "biggest citizen science project" and report sightings to help conservationists grow their population.

One of the coordinators of the count, Victoria University's Stephen Hartley, said he "wasn't about to jump to conclusions" on numbers.

"Maybe it's a Wellington phenomenon. Maybe it's nationwide," he said.

"We'd like people to go to where they've seen kereru in the past and tell us if they haven't seen them as well. People like to tell us if they've seen one but not if they don't. We want to hear both.

"It's always exciting to see what sort of results come in."

The kereru is listed as "near threatened" on the International Union for the Conservation of Nature's Red List.

Mr Pistoll said he returned to Kaitoke this morning and saw "maybe a dozen" kereru; still well down on the previous years.

"Now is the perfect time. The birds should be here," he said.

"They've got flowers full of nectar which are super delicious. The kereru usually flock to those and gorge themselves in anticipation of breeding.

"We may start getting worried if the resource dries up and they haven't visited."

Source: 1 NEWS