This year's Great Kereru Count most successful yet

Kereru play a vital role in dispersing the large fruit of our native trees. Photo / Mark Mitchell

Kiwis have counted nearly 20,000 native wood pigeons to make this year's Great Kereru Count the most successful yet.

As the week-long nationwide survey closed last night, a total 8,743 observations had been recorded, topping last year's total 7,101.

The joint effort encouraged people to spend time watching out for kereru, then reporting how many - if any - they observed to the survey website.

"While observations are still coming in, at this stage we can estimate that around 19,000 kereru were sighted throughout New Zealand - from Stewart Island to the far north," WWF's kereru count co-ordinator Tony Stoddard said.

"Whatever the exact final figure, we will have exceeded the 14,194 birds counted in 2014."

Wellington City Council environment partnership leader Tim Park said the response from the public had been "phenomenal".

"Despite atrocious weather battering the country, people really made a concerted effort to get outdoors and make kereru count."

Kereru play a vital role in dispersing the large fruit of our native trees such as tawa, miro and matai, which has given the plump pigeon the nickname "the gardener of the skies".

No other bird is large enough to fulfil this function, making the species essential for forest regeneration.

"So understanding where they are found and whether numbers are increasing or decreasing is crucial as they play an important role sustaining our native forest ecosystems."

The data was being collated with the help of the NatureWatchNZ community and would be analysed by scientists at Victoria University.

Dr Stephen Hartley, an ecology lecturer at the university, believed the citizen science project would provide useful baseline data for tracking the health of the species.

"We'll need a few more years of data before we can say whether they are becoming rarer or more common, but for now we can start to identify kereru hotspots and coldspots."

Observations made during the count period could still be recorded online at greatkererucount.nz, NatureWatch.org.nz and via the iNaturalist smartphone app.

In this year's separately-run Garden Bird Survey, a total 1667 kereru were counted, including 253 in Auckland, 184 in Wellington and 189 in Dunedin.