Conservation Comment: Pesty pet parrots

The sulphur crested cockatoo is a common sight around Whanganui and is a listed pest. Photo / 123RF

At Virginia Lake in Whanganui, if you walk past the aviary, a slightly screechy voice will usually say “Hello”, followed by very loud squawks.

Like many parrots, the sulphur-crested cockatoo is a popular pet because of its intelligence, ability to mimic human speech and entertaining, sociable personality. Parrots and parakeets commonly get let out of their cages to ride pirate-fashion on shoulders, fly around inside houses and unfortunately, occasionally escape.

The Whanganui region is now home to a significant population of sulphur-crested cockatoos, descended from escaped pets. There is a large flock in the Tūrakina Valley and another out at Kai Iwi. If any of these wild birds could be caught and sold, it would be a fairly large “nest-egg”, with a single bird valued at more than $1000. Being, however, extremely intelligent, wary and living high up in tall trees, these wild flocks will remain elusive.

Unfortunately, there is such a growing number of sulphur-crested cockatoos in this area, and in Auckland and Canterbury, the Ministry for Primary Industries has listed them as “unwanted organisms”, along with the increasingly ubiquitous eastern rosella which inflicts considerable damage on orchards.

Other regions are also taking a hardline approach to introduced parrots. Rainbow lorikeets were deliberately released in the Auckland area in the 1990s and the population increased rapidly. In the early 2000s, a successful eradication programme to remove them from the wild was initiated by the Department of Conservation, with ongoing monitoring to ensure no further breeding populations become established.

Indian ring-necked parakeets are another listed pest species. Ring-necked parakeets have invaded Europe and the population in many places, including Britain, is increasing rapidly. They are a threat to native birds wherever they become established as well as an agricultural pest. They can also cause structural damage to buildings.

Small groups of these escaped pets have been spotted in Mt Albert, Auckland and in Havelock North, although they are not yet well established in the wild here in Aotearoa. If not controlled successfully, it is only a matter of time before the flocks increase and spread across the North Island.

The damage that parrots inflict on orchards is only one aspect of the problem. Introduced species have the potential to out-compete native forest-dwelling parrots and parakeets such as the kākāriki and the kākā. This already seems to be happening in the Whanganui area, where kākā occasionally visit singly or in pairs and can be spotted hanging out at Bushy Park Sanctuary, whereas sulphur-crested cockatoos are thriving in a large noisy flock.

It is a delight to see and hear kākā flying over central Wellington at dawn between Zealandia sanctuary and parts of the town belt. It would be so great if, during a visit to Bushy Park Sanctuary in Whanganui, instead of the screechy voices of sulphur-crested cockatoos and chatter of eastern rosellas, we could hear the kākā and the kākāriki. I look forward to that day.

Margaret Beautrais is the Whanganui Regional Museum Educator

Margaret Beautrais