New Zealand Parrot and Parakeet Reintroductions
Kakapo (Strigops habroptilus)
The kakapo (photo D.Merton) is a large nocturnal flightless parrot. Kakapo originally found throughout the three main islands (North, South and Stewart Islands) of New Zealand, but declined due to predation by humans and introduced mammals. By the mid twentieth century, they were restricted to Fiordland (SW portion of the South Island) and Stewart Island. The first attempt to establish kakapo on a predator-free island was by Richard Henry, who translocated 350-400 birds to Resolution Island (Fiordland) in the 1890s and early 1900s. The population was subsequently exterminated by stoats that colonised Resolution Island soon after. Other early unsuccessful translocations included the release of 3 birds on Little Barrier Island in 1903 and 3 birds on Kapiti Island in 1912. Six kakapo were taken into captivity in the National Wildlife Centre in the early 1960s, but all turned out to be males and died in captivity. Kakapo were discovered to be lek breeders in the 1970s, and captive breeding was then deemed unlikely to succeed. The focus of the recovery program has therefore been to establish populations on predator-free islands. The translocations conducted are considered to be "conservation introductions" -- i.e., kakapo probably never occupied any of the islands historically but establishment on a predator-free island is now essential to save the species. It was further decided that all the Stewart Island population would be translocated, following research in the early 1980s showing rapid decline due to cat predation. The Fiordland population consisted of only a few old males by then and is now believed extinct. In addition to absence of predators, islands are selected on the basis of size (kakapo have large home ranges) and habitat quality.
Kakapo were initially translocated to Maud Island. Five birds from Fiordland (all male) and 4 birds from Stewart Island (3 female, 1 male) were translocated from 1974-1981. Little Barrier Island and Codfish Island then became the focus of the programme after predators were eradicated from these islands in the early 1980s (the only potential predator remaining was the kiore, or Polynesian rat). 18 birds (11 male, 7 female) were translocated from Stewart Island to Little Barrier in 1982. The 4 surviving Maud birds (2 male, 2 female) were translocated to Little Barrier the same year following stoats arriving on Maud (at 900 m offshore, it is marginally within swimming range of stoats). Translocations since the late 1980s are shown below.
Codfish Island/Whenua Hou (1396 ha, off NW Stewart Island). 30 birds (20 males, 10 females) were translocated from Stewart Island from 1987-92. One further female was discovered on Stewart Island in 1997, and she was also translocated to Codfish. Three males were bred on the island in 1997, and 3 females were translocated from Maud in 1997. Two males were moved to Pearl in 1997. The 30 remaining transmitterised birds were moved to Pearl, Anchorage and Maud Islands in April/May 1998 to prevent any poisoning during the August 1998 poison drop to eradicate kiore from the island (one male remained). All known females had been translocated to Codfish by 2001, so Codfish is now the only kakapo breeding site. Kakapo normally attempt breeding every 2-5 years, correlated with rimu masting, and a major mast year in 2001/02 resulted in a major breeding year with 26 chicks produced. While kakapo have had high survival on all predator-free islands (ca. 98% per annum), there has been little breeding until now and the 2001/02 breeding season has caused a major increase in the population.
Little Barrier Island/Hauturu (3083 ha, Hauraki Gulf east of Auckland). No further birds were translocated to Little Barrier, and in 1998 the Kakapo Management Group and Kakapo Scientific and Technical Advisory Committee decided to remove all kakapo from the island. 16 of the 22 birds released in 1982 were still alive, giving an average survival rate over 98% per annum. However, there had been little breeding (two males raised on the island in 16 years), and successful breeding has only occurred when supplementary food was provided. The size and ruggedness of Little Barrier means that intensive management of kakapo is not practical there. Two were moved to Maud Island and 2 to Pearl Island in 1996, 2 to Codfish Island in 1997, and 6 to Maud and Nukuwaiata Islands in 1998. The last 6 birds (5 males, 1 female) were moved to Codfish Island in May 1999.
Maud Island (309 ha, in Marlborough Sounds off NE South Island). 6 birds (4 males, 2 females) were translocated from Stewart Island, 1989-91. The stoats that invaded in 1982 had been eradicated. All these birds have survived to 1999. The higher mortality following the 1974-81 translocations may have been due to extreme old age of the Fiordland males (4 of the 5 died within 3 years) and very poor condition of one Stewart Island female at the time of translocation (she died soon after release). 2 birds (1 female, 1 male) were translocated from Little Barrier in 1996, 4 birds (1 male, 3 female) from Little Barrier in 1998, and 2 birds (1 male, 1 female) from Codfish in 1998. One male was moved to Nukuwaiata in 1998. Three young (2 male, 1 female) were bred on Maud in 1998. All females were moved back to Codfish by July 2001.
Mana Island (217 ha, off SW of North Island). 2 males were translocated from Stewart Island in 1992. Mana is mammal-free, and has rank grassland and regenerating forest. Both males died, suggesting that Mana may currently be unsuitable habitat for kakapo. However, both birds were in very poor condition (about 1.5kg) when translocated.
Nukuwaiata/Inner Chetwode Island (195ha, in the Marlborough Sounds). Two males were translocated from Little Barrier and one male from Maud in 1998. The fertility/breeding fitness of these males is in question, so they are being used to test habitat suitability on Nukuwaiata.
Pearl Island (500 ha in Port Pegasus, Stewart Island). 2 males were translocated from Little Barrier and two males were translocated from Codfish in 1997. In 1998, these 4 were moved to Anchorage Island, and 26 birds (13 females, 13 males) were translocated to Pearl from Codfish Island. 5 of the 12 adult females on Pearl bred in early 1999. All were returned to Codfish in mid 1999.
Anchorage Island (160 ha in Port Pegasus, Stewart Island). 2 males were translocated from Codfish Island and 4 males (of dubious fertility) were translocated from Pearl Island in April-May 1998.
Contact Don Merton.
Kaka (Nestor meridionalis)
The kaka (photo R.Morris) is an endemic forest-dwelling parrot. Kaka were once widespread throughout the North and South Islands and offshore islands, but numbers have dwindled on the mainland. The main reasons for the decline of kaka on the mainland are habitat loss through deforestation, and introduced predators such as stoats. Kaka are cavity nesters, and research has shown that females are frequently killed at nest sites by predators as well as the nests being destroyed.
Mt Bruce Reserve (mainland forest reserve adjacent to National Wildlife Centre, Wairarapa). Reintroduction. 5 wild-caught juveniles from Kapiti and 4 captive-bred juveniles (hand reared at Mt Bruce) were release June 1996. 5 captive-bred birds (parent reared) were released in June 1997. 4 adult (3-11 years) captive birds (from other captive holders) were released in September 1999. Kaka were previously locally extinct in Mt Bruce reserve, presumably due to predation. The management at Mt Bruce involves supplementary feeding (feed stations at the National Wildlife Centre) and protection of nest sites. The released birds have generally had a high survival rate and have stayed within the reserve, probably drawn by the supplementary food. The initial release showed different behaviour between wild and captive-bred birds, captive-bred birds initially staying near the release site and using feeding stations, and wild birds dispersing more widely and initially mainly using natural foods (Berry 1998). The kaka started breeding in 1998/99, which was unexpected since normally do not breed until 4 years old. The first 3 nests were all attacked by predators, resulting in 2 females being killed and the other injured. Females were subsequently closely monitored to detect nests, and nests protedted by clearing the surrounding vegetation, attaching smooth metal sheets to the nest tree and placing fenn traps around nest sites. This resulted in 6 young being fledged (from 2 nests), 2 of which survived to the end of the breeding season and 4 which had died (3 killed by predators). There was no breeding in 1999/00, a year in which few kaka attempted breeding over the whole North Island. Kaka are breeding again in 2000/01, with nesting attempts being carefully monitored and artifical nest sites provided that should protect females from predators. The plan is to continue intensive nest site management until the population reaches 10 pairs, then attempt predator control over the main 50 hectare breeding area. Contact Raylene Berry.
Northwest Nelson. Supplementation. Birds from Codfish Island released January 1999. Contact Ron Moorhouse.
Karori Wildlife Sanctuary (225 ha mainland restoration area surrounded by a mammal-proof fence), central Wellington, North Island. Reintroduction. Eleven captive-reared kaka (4 unrelated clutches) have been released into the Sanctuary between 2002 and 2004. The reintroduction is part of the restoration program in the sanctuary following eradication of mammals inside the fence (see http://www.sanctuary.org.nz). All carried transmitters on release to monitor survival and dispersal and some locally bred juveniles have also had transmitters attached. Supplementary feeding has been undertaken to encourage birds to stay within the Sanctuary and to be more easily observed. One pair bred in the first season (2002/3), and have bred every year since then. The breeding population has slowly increased, with breeding apparently limited by breeding age males - females have bred at one year old but the males have not bred until they are 2 years old, which is exciting given that kaka were originally thought to only breed at 3-4 years of age. In January 2003 an unbanded male arrived at the Sanctuary but didn’t breed until 2004/5 – he is the only known natural immigrant to the population. Breeding has occurred every year (8/9 pairs bred successfully in 2005/6) and successful double clutching has also occurred each year since 2002/3. Kaka have been increasingly seen in various parts of Wellington with some birds apparently ranging out of the Sanctuary to feed, and some deaths have been documented as a result, but at least 48 birds are known to have been in the Sanctuary in August/September 2006. Contact Raewyn Empson.
Maungatautari (3400 ha mainland restoration area surrounded by a mammal-proof fence), Waikato, North Island. Reintroduction.Seven kaka had been released as of December 2007. Captive-bred young birds are held in an on-site aviary for a period, then given access to the outside where outdoor feeders are deployed with the aim of keeping them from dispersing. The 4 females in the first group of 7 were radio-tagged, and those birds have gone further afield than expected following release and have not shown much interest in the feeders. Contact Chris Smuts-Kennedy.
Orokonui Ecosanctuary (307 ha predator-fenced mainland site 20 km north of Dunedin). Six captive-bred kaka were released in November 2008. Exotic mammals were eradicated from the sanctuary in July 2007. Contact Chris Baillie.
Red-crowned Parakeet (Cyanoramphus novaezeelandiae)
Matiu/Somes Island (25 ha, Wellington Harbour). 11 birds from Kapiti Island translocated February 2003, and additional 19 birds 21 April 2003. Breeding was detected in the 2003 cohort in October 2003, breeding began in the second cohort in July 2004. 15 birds were regularly seen in July 2004. Contact Lynn Adams.
Yellow-crowned Parakeet (Cyanoramphus auriceps)
Long Island (142 ha scenic reserve, Marlborough Sounds). Reintroduction. 20 birds from Te Kakaho (Outer Chetwode Island) released February 2001. This species would have been present on the island before it was cleared of forest for farming. They were formerly very abundant on the adjacent mainland, and are still occasionally encountered in mature forest surrounding Queen Charlotte Sound. The island is now thought to have renerated sufficiently to support the species, and the reintroduction was part of the Nelson/Marlbourough island management plan (Millar & Gaze. 1997. DoC Occasional Publication 31). Birds were caught in mistnets set by artificial water supplies, held in aviaries up to 48 h, then transported in small boxes by boat, road, and boat to the release site (max 4.5 h in transit). All birds were individually colour banded, and 6 had blood samples taken for haematological assessment. They were very common on the island by 2007 when the population was harvested for reintroduction to Motuara Island (see below). Contact Peter Gaze.
Mana Island (217 ha, off SW North Island). Reintroduction. 26 birds translocated from Te kakaho Island (outer Chetwoods) 12 April 2004. 10 were female, 12 male and 4 sex unknown. 12 birds are regularly seen in Sept 2004. Contact Lynn Adams.
Motuara Island (59 ha, Marlborough Sounds, off NE South Island). 45 birds of mixed sex were translocated from Long Island (see above) in January 07. Birds were caught in mist nets and released immediately after the 30 minute boat ride between islands. They bred within the first year and appear to have increased as of December 2008.Contact Bill Cash.
Orange-fronted Parakeet (Cyanoramphus malherbi)
Orange-fronted parakeets were reintroduced to Chalky Island (Te Kakahu o Tamatea), Fiordland, when 31 captive-reared birds were released in December 2005 and February 2006. The birds were captive-bred juveniles from the Isaac Wildlife Trust’s Peacock Springs site. They were flown by plane to Invercarbill, then by helicopter to Chalky Island. Most birds were still alive when transmitters expired (six weeks after release?) and four pairs were found nesting in late March 2006. A more research search of the island found about 16 unbanded birds from the previous year's breeding. From Forest & Bird 320: 5 and Forest & Bird 323: 15.