PHOTO
Otago wood pigeon numbers appear to have dropped 45% in the latest Great Kereru Count, and Southland numbers have plummeted 78%.
But experts are not getting themselves in a flap about it.
The Great Kereru Count called for New Zealand residents to report the number of wood pigeons they saw between September 20 and 29, to help gather information on their abundance and distribution.
The 2019 count recorded 929 kereru in Otago (down from 1689 in 2018) and 162 in Southland (down from 743 in 2018).
Nationwide, 14,248 kereru were counted this year - down 25% from last year.
While the numbers appeared to have dropped significantly in the South, Victoria University of Wellington centre of biodiversity and restoration director Stephen Hartley said he was not concerned.
Wood pigeons spent much of the winter in remote bush and returned to urban areas in spring, to feed on nitrogen-rich foods such as willow, and to breed.
''With the bumper fruiting season this spring, there was unusually high amounts of forest fruit, so one possibility was that kereru have been staying deep in the forest, rather than venturing out into towns and cities.
Kereru count co-ordinator and Kereru Discovery director Tony Stoddard said the birds were able to fly up to 70km in a day, and so lower numbers being reported in towns and gardens may not be all bad news.
''Just like my Labrador-cross dog, kereru will go out of their way to follow their favourite foods.
''Kereru feeding on native forest fruit is exactly what they need to do, as they play a crucial role in dispersing seeds of large trees like tawa, taraire, hinau and miro.
''This is why they are known as gardeners of the sky.''
Mr Stoddard said another reason for the drop might be due to fewer people taking part in the count.
This year's count had broader reach than last year, with 6700 observations from Kaitaia to Stewart Island.
However, the number of observations was down from 8500 last year.
Dr Hartley said the aim of the count was to build a comprehensive longitudinal study of how the pigeon was faring.
Now in its sixth year, the count needed eight years of data to help New Zealand understand how best to restore healthy and abundant populations of the bird.
''The count doesn't tell us exactly how many kereru there are in the country, but over time it will tell us if numbers start to increase or decrease in certain areas relative to others.''