James Dryburgh reports on how recent collaborative efforts to save the Critically Endangered Norfolk Island Green Parrot are proving to be a great success—and it’s not just the parrots that are benefitting.
Originally published in Australian Birdlife
Photo: Coral Rowston
Only two years ago, the Tasman Parakeet was in serious trouble (see “Parrots in Peril”, Australian Birdlife, September 2013). Having been rescued from the brink of extinction once before—when, in the late 1980s, the number of breeding-aged female parrots dropped to four—it was thought that the population had crashed again to less than 50 birds. This would make the Tasman Parakeet, or Green Parrot, as it is known by Norfolk Island locals, one of the rarest species in the world.
Dr. Luis Ortiz-Catedral from Massey University arrived on the Island in July 2013 to assess the situation. Invited by a team of representatives from Island Conservation, BirdLife Australia and The Nature Conservancy, he hoped to develop a reliable survey method to determine a population estimate. Even though the Island is only 8 by 5 kilometres, it took four days for Dr. Ortiz-Catedral to see his first parrot, and his final population estimate was between of 45-96 individual birds—of which only 12 females were confirmed.
The surveying revealed that one of the issues facing the Green Parrot was a lack of safe nesting sites. In previous conservation efforts, many artificial nest hollows had been constructed in the hopes of reducing the risk of predation by rats or cats. However, these nests were only maintained for a short period of time and subsequently became waterlogged, broken or dislodged. With the added pressure of stiff competition from introduced Crimson Rosellas, European Starlings and feral bees, very few natural or functional artificial nesting sites remained for the Green Parrot.
Having identified these challenges to the Green Parrot population, the Norfolk Island National Park team led an emergency nest restoration program, coupled with far more intense rat and cat control in and around the Norfolk Island National Park, where almost the entire the Green Parrot population survives. The impact of these actions has been clear and rapid. In early 2015, application of the same survey method used in July 2013 revealed a six-fold increase in the number of Norfolk Island Green Parrots, with a new population estimate of 200-400 birds and a more even ratio between the sexes.
Conservation: a collaborative effort
This dramatic increase in the population can be attributed to a holistic and integrated approach to conservation by a range of organisations operating in collaboration with the local community.
One of the major initiatives has been the significant expansion of measures to control introduced predators such as Black and Polynesian Rats within the Norfolk Island National Park. Led by Parks Australia, the project covers 5 square kilometres of hilly north-western Norfolk Island as well as approximately 2 square kilometres on the nearby Phillip Island. In tandem with this, the conservation organisation Wildmob have been implementing a co-ordinated rat control program in partnership with local landholders on key areas of private land adjacent to the National Park.
‘Voluntourism’ is providing a significant boost to these projects. During their stay on Norfolk Island, Wildmob’s volunteers undertake conservation work with help from expert guides for half of each day for a week, and are free to explore the Island for the remaining time. Working alongside local conservation groups, these volunteers have made a major contribution to conservation efforts through weed removal, native plant re-establishment and pest control, both within and extending beyond the National Park.
While the volunteers enjoy the opportunity to travel to such a unique destination, meet the locals and gain an intimate experience of the natural and cultural environment, their presence also helps to demonstrate the value of the Green Parrot both to Norfolk Islanders and the broader Australian community. There are 57 other threatened species on Norfolk Island—along with hundreds of thousands of breeding seabirds—and the conservation actions being put in place to support the parrot population are already producing positive outcomes for many other species.
Regular community talks are provided by the knowledgeable and passionate park rangers and advocates on the island, and updates on the Green Parrot conservation program are published in the local newspaper. Culturally, Norfolk Islanders see themselves as genuine caretakers of their land. This may be due in part because an interest and respect for environmental surroundings are heightened when your home is a tiny island in the middle of the vast Pacific Ocean. The bright future of this parrot is fast becoming a symbol of environmental success for the entire Norfolk community.
The Norfolk Island Green Parrot story is also a great example of the significance of islands in terms of their biodiversity: on the one hand, islands are particularly sensitive and their ecosystems can be impaired quickly but on the other hand, these constraints also mean environmental restoration can have a significant impact. Norfolk Island is demonstrating the power of a ‘restoration culture’ that can undoubtedly be applied elsewhere to help rejuvenate populations of precious endemic birds.
Translocation to Phillip Island
Past efforts to save the Green Parrot have shown that unless a permanent solution to address threats can be found, as soon as intensive management regimes are relaxed, a rapid decline in numbers soon follows. For this reason, the establishment of an insurance population on Phillip Island is critical to ensuring the long term survival of the species. Now free of feral cats, rats and rosellas—and uninhabited by humans—Phillip Island is ideally suited. However, as the parrots are still so rare, their population on Norfolk Island must grow before the translocation can be attempted. In preparation for this translocation, significant revegetation and weeding work has been carried out on Phillip Island and Parks Australia has also been investigating the dispersal and movement patterns of Green Parrot fledglings from their nests, to build on our understanding of their ecology.
A study of the parrot’s diet has also been conducted, with the analysis of 400 records revealing that they feed on 26 different species of plant and primarily seeds and fruit. Norfolk Pine seeds and Nikau Palm seeds made up 24 per cent and 18 per cent respectively of all observations, making them the major food sources for the parrot.
Experience from elsewhere, such as the islands off the coast of New Zealand, has shown that parrots in the Cyanoramphus genus (such as the Green Parrot) can establish populations in challenging environments. This is in part due to their generalist diet, as well as their willingness to nest on the ground in environments that are free of rodents and cats. In May this year, a study of the availability of the main food sources of the Green Parrot on Phillip Island was carried out. Considering the seriously degraded state of Phillip Island—where almost-barren terrain replaces the once dense vegetation—it was necessary to determine if there would be enough food for the parakeets to establish thhttp://jamesdryburgh.com/wp-admin/edit-comments.phpemselves.
The study found that while Nikau Palms are rare on Phillip Island, other potential food resources such as Norfolk Pine, White Oak and the exotic African Olive are abundant. Plants which have been recorded as part of the diet of the related New Zealand parakeets are also common. The presence of Norfolk Pine is particularly significant in light of a study that found that during the crucial winter period, Norfolk Pines seeds made up 60 per cent of observed diet of Green Parrots. Given this variety and abundance of plants, it was decided that food availability on Phillip Island should not pose a problem to their successful relocation.
Another critical factor in the long term viability of an insurance population is ensuring that pests don’t re-establish. A potential risk is that rats could be introduced via boats to Phillip Island, and so the Norfolk Island community have been working with Parks Australia to significantly improve biosecurity on Phillip Island, via improved management regimes and educational programs about the reintroduction of potential predators.
With endemic vegetation gradually reclaiming Phillip Island and the not-too-distant prospect of the Green Parrot arriving too, it is possible to imagine that with a few more years of good work, a flourishing ecosystem and travel destination can be achieved: something akin to the Galapagos, but where travellers visit less to witness Darwinism than to experience a unique environment that was miraculously brought back to life.