Serious Cause for Concern - New Zealand’s Parrots in the 21st Century
Photographs © Rosemary Low
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I was on the island of Tiritiri Matangi in the Hauraki Gulf, not far off the coast of Auckland. My heart soared as I watched them flying, perching and preening. They seemed to me larger and more solid-looking than the captive birds we know. They looked so beautiful with their ruby-red eyes!
The story of this population is an interesting one. The 220 hectares of Tiri (as the island is often known) were originally covered with forests of native trees. After centuries of Maori occupation and farming by Europeans, hardly any forest had survived and most native birds, including the Kakariki, had gone, their disappearance assisted by introduced cats, stoats and rats.
Then the Department of Conservation (DOC) took over the island to try to return it to its native state as an open sanctuary. Hundreds of thousands of trees were planted, mainly by visiting groups, including schools, who volunteered their time. Some of the rarest bird species, including Kakariki and Little Spotted Kiwi, were introduced as the vegetation regenerated. Today there is much forest and abundant native birdlife — often endearingly fearless in a landscape whose birds once knew no fear because there were no mammalian predators.
The Kakarikis on Tiri Tiri Matangi thrived and currently the population is estimated at about 800 birds. I was shown a site where parakeets roosted low down in a hole in a bank. Perhaps their favourite food is the seeds of the giant flax that are such a prominent feature of the island’s flora.
The parakeets have been studied since 2004 by Mexican biologist, Luis Ortiz-Catedral, as part of his Master’s degree. Using infra-red video cameras, he obtained information on how often the chicks were fed by their parents, for example. On May 17 2009, Ortiz-Catedral took part in the translocation of Red-fronted Kakarikis from the island of Little Barrier (visible from Tiri and much larger) to the 179-hectare island of Motuihe, also in the Hauraki Gulf. More than 200 conservationists witnessed the release of 31 birds, 16 males and 15 females. They were flown in by helicopter, carried in cardboard boxes and released into a glade of native pohutukawa trees, famous for their abundant red blossoms like pom-poms. Some of the Kakarikis had been fitted with tiny transmitters so that their progress could be followed. Sadly, nine others had died in holding aviaries en route.
Motuihe had been cleared of predators and this release was part of a three-year project to translocate Red-fronted Kakarikis from Little Barrier. Twenty more will go to Motuihe, at a time that avoids the October to February breeding season. The next location to receive them will be Rakino Island followed by Tawharanui Regional Park near Auckland.
During the translocation from Little Barrier, 54 parakeets were caught and feather samples were collected for molecular screening. In 15 individuals the virus for PBFD (psittacine beak and feather disease) was detected, but only two birds showed external signs of the disease — abnormal feather formation and/or coloration, loss of feathers and feathers with blood in the quill (haemorrhagic). This was the first positive identification of PBFD in wild endemic New Zealand parrots. It confirms the risk of the spread of the disease between wild populations. The report was published in Emu on August 25 2009.
Kakapo
Both the first two issues of this magazine carried updates on the exciting events of the 2008/09 breeding season. It was the long-awaited most successful breeding season since Kakapo have been under human management. An incredible 29 of the 38 breeding-age females nested; 27 females produced 28 clutches, resulting in 71 eggs! Of these 50 were fertile. This represented about 70% of eggs laid, an increase on the two previous breeding seasons, aided with the use of artificial insemination.
Thirty-six chicks hatched and 33 survived — 20 males and 13 females. For the first time the human-managed population exceeded one hundred Kakapo! Seven were parent-reared in natural nests and the rest were hand-reared away from Codfish Island where they hatched. The chicks could not have survived without intervention, as most of the rimu fruit, on which Kakapo depend for rearing, failed to ripen.
The large, flightless Kakapo (Strigops habroptilus) is the most unique of all parrots - probably the most unique bird to have existed in historical times due to its extraordinary breeding biology and physical attributes. It is perhaps also the most charismatic, even the most endearing. It is also one of the most critically endangered.
Because they are nocturnal and flightless, Kakapo were almost wiped out by introduced predators such as cats, stoats and rats. These trusting parrots were killed in their thousands two or three centuries ago, for skins, for food and even to feed dogs. Then, from the early 1980s, the threat from mammalian predators was the reason for the removal of the few surviving birds to offshore island reserves that had been cleared of predators by the Department of Conservation. Eight different islands have been used. Kakapo are officially declared extinct in the wild, although, of course, they live at complete freedom on the island reserves.
Codfish (Maori name Whenua Hou) is a small island just off the south coast of South Island. Nearly 4km (2 ½ miles) of turbulent ocean separates it from Stewart Island to the east. It was on Stewart that the last wild population of Kakapo was discovered in 1977. Before that, the species was believed to be effectively extinct, as only males were known to survive. Females were especially vulnerable to predation as they tended their nests on the ground. Kakapo breed approximately every three years, being stimulated by the fruiting of the rimu shrub.
Synonymous with the story of the Kakapo’s last-minute reprieve from extinction is the name of Don Merton. His involvement with Kakapo commenced in 1958, as a trainee with the Wildlife Service. He was part of the team that searched for this species on the mainland when it was almost extinct there. Until the day he retired in 2005, his contribution to the Kakapo Recovery Programme (especially as leader) was enormous. His understanding of this parrot and its biology, his intuition and his determination were major factors that prevented its extinction. His career was remarkable and recognised worldwide and in New Zealand with awards such as the Queen’s Service Medal 1989 (conservation of endangered species) and “one of One Hundred Great New Zealander’s of the 20th Century” (1999).
This century started with only 62 Kakapo in existence, every one monitored. Then in 2002 occurred the most productive breeding season since intensive management began (in 1989). It went on to become a year of quite extraordinary success with twenty-four chicks reared! By the first week in February, 19 of the 21 females had either mated or laid. A team of volunteers watched the nests every night to ensure the chicks came to no harm while the female was out foraging, and heat pads were used to ensure the eggs did not chill.
Kakapo nested again in 2005, adding another four young to the population. For the first time ever, members of the public had the opportunity to see Kakapo on June 18 2005. The four young were put on display in a glass enclosure before being moved from the rearing unit in Nelson to Codfish Island. Several thousand people queued in the rain to see them.
In 2006 the paying public had the opportunity to see a hand-reared male Kakapo called “Sirocco”. Uniquely, he proved to be too imprinted for breeding purposes. DOC decided to display him for several weeks on Ulva Island. Taking a boat trip to the island, thirty people were able to view him in a night. These included three visitors who had flown in from the USA especially for the purpose.
In 2008, eight chicks were hatched. One died shortly afterwards due to septicaemia. Probably due to a shortage of food, females were spending long periods off the nest, so the other seven eggs were artificially incubated. All hatched and six were reared, three males and three females. This brought the total Kakapo population to 91 - 44 females and 47 males.