Red-crowned parakeet

• Mainland red-crowned parakeet, C. novaezelandiae novaezelandiae[4]
• Chatham red-crowned parakeet, C. novaezelandiae chathamensis[4]
• Kermadec red-crowned parakeet, C. novaezelandiae cyanurus[4]

Since many of the Cyanoramphus species are very morphologically similar, several of them have only recently been upgraded to the species level in light of results from molecular analyse.

• Reischek's parakeet, C. hochstetteri[3]
• New Caledonian parakeet, C. saisseti[3]
• Lord Howe parakeet, C. subflavescens[5]
• Norfolk parakeet, C. cooki[3]
• Forbes’ parakeet, C. forbesi : There is much debate regarding the taxonomic status of the Forbes’ parakeet. It was first described as a distinct species, but was later considered a subspecies of red-crowned parakeets or yellow-crowned parakeet. However, more recent genetic studies concluded that it should be classed as a separate species within the genus Cyanoramphus. Although it remains the closest genetic relative of the red-crowned parakeet, the Forbes’ parakeet differs slightly in voice, colour, morphology, as well as possibly ecology and behaviour. Moreover, hybrids rarely occur as individuals tend to mate with members of their own group. This species seems to have independently derived from the Chatham red-crowned parakeet.[4] Others suggest it might be the result of hybridisation.[3] Overall, at present, the Forbes’ parakeet is still considered a distinct species.
• Macquarie parakeet, C. erythrotis †: New DNA analysis is required to determine the correct status of the Macquarie parakeets, as the specimens used in Boon, Kearvell et al. (2001) were not correctly authenticated.[6]

Red-crowned parakeet are green parrots with large tails. They are easiest to identify by their bright yellow-green plumage, and crimson forehead, lores, eye-stripes and front of the crown. They also have red patches on either sides of the rump. While they are flying, their dark blue outerwing can be visible. Red-crowned parakeets have grey or pale brown legs and feet. Their bills are white to grey with a black tip.[7][8]

Females are slightly smaller with a yellow stripe on the underwing. Their bill is also smaller and narrower.[7][8]

Juvenile red-crowned parakeets look similar to adults. However, their bill has a slight pinkish tinge. Moreover, the iris of young parakeets starts off as dull black or brown, and becomes increasingly red as they age. Juvenile males also sport a stripe under the wing like the females.[7]

[2]

We can recognise red-crowned parakeets by their soft musical chattering calls. Those vocalisations are stronger and lower-pitched than the yellow-crowned parakeet's. During flight and take off, they also emit a ki-ki-ki-ki-ki or kek-kik-kek sound.[2]

Red-crowned parakeets can live in a wide variety of habitats including dense temperate rainforests, coastal forests, scrubland, forest edges and open areas.[8] When their range overlaps with Yellow-crowned parakeets, red-crowned parakeets favour forest edges and open areas.[9]

Red-crowned parakeets were once widespread across the North and South Island of New Zealand. Nowadays, however, most of those mainland populations have disappeared due to predation by introduced species.

On the mainland, this species occurs in large forest blocks in Northland, Coromandel and central North Island. In the South Island, there has been records of them along the West, South and South-East coasts. Nevertheless, those mainland populations remain extremely scarce. The rest of the species is confined to Stewart Island/Rakiura and a number of offshore islands (such as Kapiti Island, Tiritiri Matangi Island[10] and Matiu/Somes Island) as well as the Auckland Islands to the south. The other subspecies live on their respective islands, namely the Kermadec Islands and the Chatham Islands.[2]

Red-crowned parakeets are highly generalised and diverse when it comes to feeding. They consume flowers, fruits, seeds, leaves and buds from a variety of plants. They also complement their diet with a few invertebrates such as small aphids and can be fed mealworms. Their feeding habits vary throughout the year depending on the seasonal availability of food. In winter and spring, the birds mostly eat flowers. In summer and autumn, their main food items consist of seeds.[9]

Red-crowned parakeets form monogamous pair bonds. Couples may or may not stay together after a breeding season, possibly depending on the success of their nesting success.

Courtship feeding and other pair bond behaviours begin to take place about two months before laying the eggs, in mid-October. In the beginning of October, males begin to escort their companion to inspect potential nest sites. While he stands guard in front a hole, the female cautiously explores it. She communicates that she found a suitable one by repeatedly entering and exiting the hole. The female then proceeds to excavate a hole up to 10–12 cm deep and 15 cm wide in the floor of the nest chamber with her upper mandible and feet. Wood chips from the walls are chewed and used as substrate. Throughout the whole nest-building process, the male remains nearby, feeding himself and his mate as well as chasing other parakeets away. Successful breeding pairs have been seen coming back to the same nesting location the next year.

Nests are mostly found in the holes of large healthy trees, although cavities of other kinds are not excluded. These include holes in cliffs, cavities amongst the roots of plants, abandoned seabird burrows and manmade structures. It has also been noticed that a majority of nest entrances face north.

Egg laying takes place from November to January, peaking in December. On average, clutches count 7 eggs, yet can range from 4 to 9. Eggs look oval and white with a slight gloss which fades during incubation. In red-crowned parakeets, only the female incubates. While in the nest, they are seen turning their eggs regularly. Otherwise, they spend their time sleeping, preening or digging. This period last from 23 to 25 days. Again, males visit the nest regularly to feed their companion by regurgitation.

The eggs do not hatch all at the same time. Some chicks can emerge several days after the first one. The hatchlings are born sparsely covered by light grey down and weigh on average 4.6g. They can already produce strong, high-pitched sounds. However, the young are altricial, born completely dependent on their parents to fulfill their basic needs. The first couple of days, the chicks are fed a clear viscous liquid brought by the mother. They are later able to eat solid ground particles. Around day 9, when the nestlings can open their eyes, the male is invited back into the nest. From thereon, both parents take care of feeding their offspring. 30 days after hatching, the chicks have developed feather on most of their body and have grown up to about 83g. They then begin leaving the nest, but remain perched or living on the ground in the vicinity of their nest. The parents still visit their young to provide them with food. It is only 10 days after fledging that the young birds begin to feed on their own. They finally acquire complete independence 4 to 5 weeks after leaving the nest.[11]

Note that differences timing and clutch size might be observed between different subspecies of red-crowned parakeets considering they live in regions with different environmental conditions.

Various reintroduction attempts have been studied. Between 1976 and 1986, seventeen red-crowned parakeets were released in the Waitākere Ranges near Auckland. The project was not monitored very meticulously and it apparently failed.[12]

More recent attempts on Tiritiri Matangi Island, New Zealand from 2004 to 2006 concluded that reintroduction can succeed in areas free of introduced predators.[13]

Recent research conducted on Little Barrier Island, New Zealand, has confirmed the presence of the psittacine beak and feather disease (PBFD) amongst the local red-crowned parakeet population.[14]

In the Māori language, noisy chattering or gossiping is likened to kākāriki chicks calling in the nest via the phrase "Ko te rua porete hai whakariki" (just like a nest of kākāriki).[15]