Exotic parrots are on a non-stop flight to becoming a menace in New Zealand, as pet owners release hundreds of them into the wild each year and, in doing so, put the survival of native birds at risk.
Roughly 6% of New Zealanders own pet birds and an average of 331 of the animals are lost each year; 92% of these are exotic parrots, mostly in the Auckland region, according to the University of Auckland.
The numbers are conservative because scientists rely heavily on bird-owners reporting that they have lost their parrot, the university’s associate professor in biological studies, Dr Margaret Stanley, said. In some cases, people would not report it online, and in other cases, they were deliberately releasing them, she said.
She has run simulations on the probability of pet parrots of the same species being found in the wild together, which would give them an opportunity to breed and eventually compete for the same food and nest space as native birds.
“We looked at all the details on survivorship and lifespan for these species, and what we found was that for the seven species that we modelled, it was more than an 80% chance that a male-female pair were at large in the same local board area, at any given time. That was actually 100% for the Indian ring-necked parakeet and the Alexandrine parakeet – even worse, because we know these two species can hybridise.”
The parrots also run the risk of introducing diseases, which is bad news for the 40% of New Zealand’s birds already considered endangered. “Once they’re breeding, it’s very, very hard to eradicate or control them,” Stanley said.
Auckland Council’s biosecurity principal biosecurity adviser Dr Imogen Bassett said the results do not surprise her.
“We do see regular reports of parrots on ‘lost and found’ pages on websites, and we get people calling council saying they’ve seen parrots, so they’re definitely out there. I think people generally underestimate the extent to which they are around.”
From 1 September, Aucklanders will be banned from breeding and selling a number of exotic parrots, including monk parakeets, ringneck parakeets, and rainbow lorikeets, under the city’s pest management plan.
“They have a massive track record of being invasive in dozens of countries and posing a real problem,” Bassett said. “That’s why research like Margaret’s is particularly concerning because it does really highlight the depressing risk we have of joining all those other countries.”
That’s riled some owners and breeders in Auckland, but Bassett said consultation is under way over some parrot species that are already common in the environment, including eastern rosellas.
“The horse has already bolted [for rosellas], so the ones we are most concerned about are those that we don’t already have wild populations of.”
Bassett says New Zealand has the opportunity to stamp out a parrot invasion now, unlike when possums, rats, rabbits and other pests were introduced to the country in the 19th century. “Now 150 years later, we’re picking up the pieces of that very expensive and messy problem. We know with biosecurity that prevention is better than cure.”
Stanley added that it cannot be just a regional approach, there must be a nationwide ban. “At the moment you can buy one on TradeMe from Hamilton and get it sent to Auckland, and breeders are talking about moving out of Auckland to set up shop.”
“[Regulation] is a little bit toothless if it’s not nationwide.”