New Zealand Pigeons on a plum binge
Posted By QEII National Trust | September 1, 2021
Written by Ines Stäger
Ines Stäger is QEII a covenantor, based in the Central Canterbury region. She is a landscape architect in Geraldine, sits on the board of the Royal Forest and Bird Protection Society and a committee member of the local branch.
Over the last four weeks we have been observing several New Zealand pigeon / kererū / kūkū / kūkupa, eating plums from our trees.
We did not consider the fruit being ripe until about a week ago, but this did not seem to matter to the kererū. They do not pick on the plums but swallow a whole plum, one after another. It is quite an acrobatic act the way they turn each oval shaped plum in their beak before it finally makes its way down the throat into its crop. The route of each plum into the crop is easily observed from the outside. There are several repetitions of the act of devouring plums, and several plums plummet to the ground and at some stage they are dragged away, presumably to be eaten by blackbirds.
I have read that the fruit ferments and that kererū subsequently get drunk. We haven’t noticed any drunkenness; however, the birds fly away a bit lower than usual, but this could be a result of the weight they gain in one sitting! They visit several times a day, and these performances will end shortly as there are very few plums left.
In the past we have observed kererū eating entire poroporo fruit, one after the other. The yellow fruit of poroporo seemed more easily manageable than the plums.
We are more than happy to share the plums with kererū, however there is one drawback – we don’t have control over where they disperse the stones eventually, which means ongoing weed control for us and others.
We are fortunate to have the presence of these birds around us all year. During the winter, they strip leaves off kōwhai and tagasaste. Buds of kōwhai and plum trees seem to be their favourite in the spring. The fruit of totara, kahikatea and matai as well as fruit from other species, plus the stone fruit provide plenty of opportunities for their meals during summer and autumn.
Since the extinction of moa, kererū are now the only fruit eater that can swallow large fruit and, therefore play an important role in the seed dispersal of large fruit of our forest ecosystems.
While we don’t have very many large fruit bearing native species in our forest ecosystems, it is a different story further north. Kawakawa, karaka, miro, nīkau, pūriri, tawa, taraire are some of plants that rely on native pigeons to disperse the seeds so new seedlings will be thriving somewhere. The disappearance of these birds could be a disaster for the regeneration of our native forests.
People easily recognise and enjoy seeing these large, colourful, and often clumsy birds. Despite their large size, there is no shortage of threats to them. Possums compete for food and go for the eggs, rats, cats, stoats etc. make their lives uncomfortable. Predator control is essential to ensure we will see plenty of kererū in years to come.