He said the goose population had “gone crazy” over the past three years and estimated 300 to 500 lived in and around the Gordon Carmichael Reserve in Bethlehem, as one example.
He believed they were “damaging” the reserve’s ecosystem.
“You see fewer ducks at the reserve now because there are more geese and you only have to look to see how polluted their waterway is.”
The two species typically cohabited but the extra geese meant they were all fighting for food sources.
Rayner said the geese were territorial and aggressive, especially mothers during the summer breeding season, and this could be dangerous for children visiting the reserve.
The geese bred successfully in New Zealand because of its warm climate and absence of natural predators.
He urged Tauranga City Council to take more action because, if it was not an issue now, it would become one if the population kept growing.
Neil Donaldson said he was biking through Gordon Carmichael Reserve when a Canada goose flew across his path and caused him to tumble to the ground.
He said his fall earlier this year resulted in a torn shoulder and scraped knee.
“I don’t know what the answer is in today’s world – I was brought up on a farm so I’ve got answers from 30 years ago but you can’t do that any more. I know and I understand that.”
In his opinion, the overpopulation resulted in fewer ducks at the reserve, bank erosion and a concerning amount of excrement across the park.
“I would assume competing with large quantities of geese who eat similar amounts as a flock of sheep may be the reason for less species of a few birds at the park,” Donaldson said.
The Bay of Plenty Times posted on social media asking locals who visited the reserve for their views. Some shared their concerns about waterways being polluted by goose droppings, while others worried the geese had driven away other wildlife.
Others reported having to dodge goose “landmines … bigger than dog s***” and seeing geese with goslings attacking small dogs and children. One said she would not take her child to the playground because of it.
Some commenters had no problem with the geese and said off-leash dogs were the issue as they were known to chase and harm the birds.
Tauranga City Council environment team leader Paul Greenshields said he was aware of concern about the large numbers of geese living and feeding within the city’s open green spaces.
The council had not received any reports of fewer ducks at Gordon Carmichael Reserve or of polluted waterways.
“Due to their high mobility and the restrictive nature of an urban environment, control methods are limited,” Greenshields said.
“The most effective technique used is egg addling, where the eggs are painted with an oil-based natural liquid that prevents development and therefore it does not hatch.”
The council addled more than 300 eggs last spring across city reserves such as the Kōpurererua Valley and Gordon Carmichael Reserve.
A city-wide pest management strategy was being developed in the next three years that would provide high-level guidance and kick off pest animal control plans “implemented either by species or by reserve outcomes”.
The council was also looking into modifying parks and reserves through planting to limit the space for geese to graze.
How Tauranga Airport deters geese
Tauranga Airport manager Ray Dumble said its deterrents for geese included bird-scare cannons, lasers, pyrotechnic screamers and bangers.
“Occasionally, there are geese in the vicinity of the airport, but they … have caused no issues in the past 20 years.”
Canada geese are classed as an unprotected species after being moved from schedule 1 of the Wildlife Act to schedule 5 in 2011, which meant they are no longer considered game birds.