Adults have been known to feed their chicks small fish, frogs, mammals and birds, as well as carrion, but pukeko are for the most part vegetarians.
They are also good swimmers, and will readily paddle their way across ditches or ponds. For all their lowly status in this country, swamphens have been held in high regard by other cultures. These attributes were noted by the early natural historians in New Zealand. The brightness of its plumage and the extreme elegance of its movements at once arrest and please the eye, while, on the other hand, it is in very good repute as a game bird.
Perhaps today we take pukeko for granted. They are not endangered, like many of our native bird species, and can be abundant in some areas. Although they prefer to breed and nest in marshy areas, they spend considerable time foraging for grubs and grasses in adjacent pasture land. In fact, the pukeko is one of the few native species to have expanded its range and increased in numbers with the clearance of native forests for farmland, although this trend has been reversed in areas where swamps have been drained.
Commo though they may be, pukeko have a low public profile compared to many other native birds. I am always impressed by how much the average person knows about the habits and natural history of kakapo, kokako, and takahe, despite theirnever having seen one in the wild. Yet the same people are almost shocked to discover that the pukeko they see feeding in drainage ditches along the roadside can actually fly.
That being the case, I suppose these people would be flabbergasted to find out that pukeko often live in communal groups, mate with several partners many of which are close relatives and sometimes exhibit homosexual-like behaviour. Yet this is precisely what research on pukeko over the past 20 years has revealed. There is a lot more to this ungainly bird than the image conjured up in the minds of many New Zealanders of a dumb bird that frequently gets hit by cars.
As it turns out, the pukeko may have one of the most interesting and complex social systems of any bird species in the world. John Craig of the University of Auckland was the first to investigate the social dynamics of pukeko.
At one study site near Linton in the Manawatu, Craig found low pukeko densities and birds breeding as pairs. Territories were small, and each male had a relatively short boundary to defend against one other neighbouring male. In contrast, pukeko at a second Manawatu site near Pukepuke bred and lived in groups consisting of adult males, 2 adult females who bred promiscuously with each of the males , and nonbreeders who were offspring from previous broods.
Unaware of the existence of these communal tendencies in pukeko, early naturalists were surprised by their exceptionally high clutch sizes. We now know that these large clutches are cases of communal nesting. They can be verified because each female lays eggs with a distinct colour and spot pattern; on careful investigation two sets of eggs can be identified in the shared nest. But why would females want to share a nest in the first place?
Craig did not come up with a satisfactory answer to this question, but he did make two important observations that allowed him to speculate why males sometimes share territories and mates. Second, he estimated that males breeding as pairs in Linton produce more chicks per capita than do males breeding in groups in Pukepuke. Here, pukeko groups were even larger than those in the other study areas, containing adult males, 2 adult females and non-breeding helpers.
Within each group there was a defined pecking order or dominance hierarchy among both males and females. A dominant bird holds its head high and fluffs up its plumage; a submissive bird bows, holding its head close to the ground and exposing its vulnerable tail. Already a subscriber? Login now to keep browsing. You can unsubscribe from these at any time. The extra articles will expire at the end of the month. New registrations only. View our latest special offers for further discounts and benefits.
See more, do more, live more. Share with friends. Read more from the June Issue. A well-recognised and relatively common bird, it is a colourful character but does have an aggressive and quite nasty streak.
Cookies required When you have enabled cookies, you can refresh this page and continue reading. Birds may nest as monogamous pairs but can also form polyandrous, polygynandrous and, more rarely, polygynous groups.
Any of these groups may also have non-breeding helpers. Clutch size is typically eggs per females and when multiple females contribute to a single nest the total clutch size can be as high as 18 eggs. Incubation is predominantly by breeding males, with some assistance from breeding females.
All group members contribute to chick care. Incubation begins midway through laying and lasts days. Hatching is spread over several days, but is more synchronous than laying. Chicks begin leaving the nest after days, but are fed by adults for c.
In the North Island, laying can occur in any month, with a peak in August to November. In the South Island, breeding normally takes place between September and January. Pukeko are commonly seen foraging in paddocks and along roadsides. When disturbed, they prefer to run or hide rather than fly, but once airborne, they are capable fliers and can fly long distances e. Despite not having webbed feet, they are also strong swimmers.
Pukeko are territorial, and aggressive interactions between birds from neighbouring groups are common. Such territorial interactions are noisy affairs and often involve several birds from each group. Occasionally, aggressive interactions escalate to full on fights where individuals bite and kick one another. Territorial defence is typically performed by males. Adult pukeko have few natural predators. Juvenile birds are often targeted by swamp harriers, but adult birds will fight vigorously to defend their offspring.
Pukeko have been observed attacking cats and stoats. Pukeko are primarily vegetarian, but animal foods make up a small proportion of the diet. Most common foods are the stems, shoots, leaves and seeds of grasses e. Poa , Glyceria , and Anthoxanthum spp. Carex and Scirpus spp. They also eat garden vegetables and crop plants.
Animal foods consist mostly of insects, spiders and earthworms however there are rare reports of pukeko taking larger prey such as frogs, lizards, fish and nestling birds. The bill is used to cut, rip or dig up plants which are typically held and manipulated in the foot i. Carrol, A. Food habits of pukeko Porphyrio melanotus Temminck. Notornis 13 : Clapperton, B. Vocal repertoire of the pukeko Aves: Rallidae.
New Zealand Journal of Zoology 11 : Craig, J. The behaviour of the pukeko, Porphyrio porphyrio melanotus. New Zealand Journal of Zoology 4 : Pair and group breeding behaviour of a communal gallinule, the pukeko, Porphyrio porphyrio. Animal Behavior 32 : Handbook of the birds of the world.
Lynx Edicions,Barcelona. Jamieson, I. Testing reproductive skew models in a communally breeding bird, the pukeko Porphyrio porphyrio.
Proceedings of Royal Society of London B : Marchant, S. Handbook of Australian, New Zealand and Antarctic birds. OxfordUniversity Press, Melbourne.
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