Guest post from Dr Ray Nias, Island Conservation Southwest Pacific Regional Director.
The ongoing decline of biodiversity on Norfolk Island dramatically exemplifies a central weakness in the current approach to threatened species conservation in Australia, as well as the potential benefits of an island eradication approach to invasive species.
The biodiversity of Australia’s Pacific Island territory is under serious threat from invasive species because of the chronic shortage of funds and expertise, major administrative barriers to accessing Australian government resources and neglect by mainland Australia.
Australia remains a world leader in restoring island biodiversity as demonstrated by the removal of rabbits and rodents from Macquarie Island, the proposed eradication of cats and subsequent reintroduction of endangered species to Dirk Hartog Island and the recent completion of the world’s largest island ant eradication on Melville Island. However major challenges remain for conserving Australia’s island biodiversity, as the situation on Norfolk Island clearly shows.
Invasive species and extinctions
The arrival of invasive alien species such as rats, cats, ants and weeds has had profound impacts on islands around the world. The majority of all recorded extinctions have taken place on islands and the bulk of these extinctions are directly attributable to the impacts of invasive vertebrate predators and competitors.
On Norfolk Island, the presence of invasive species may have been a major factor in the extinction of at least six bird species and the possible recent extinction of one more, the white-chested white-eye (Zosterops albogularis). The Tasman parakeet (Cyanoramphus cookii), or green parrot, as it is known on the island, is another bird species under major threat of extinction. Having been saved from the brink of extinction once already, the green parrot is back on the critically endangered list. A further 46 plant species, five species of land snails, five bird species and two reptiles are currently listed under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).
About Norfolk Island
Despite its history of extinctions, the biodiversity of Norfolk Island remains significant. According to Brooke et al. (2007), Norfolk Island is ranked as number 11 in the world’s ‘top 20’ islands, with areas less than 1000km2, ranked in terms of conservation benefit to threatened birds arising from the eradication of alien vertebrates from those islands.
Species conservation is possible
Although the conservation of many threatened species in Australia often seems an almost intractable problem, there are a number of factors that might lead one to the conclusion that this should not be the case on Norfolk Island.
A small area to manage
The area that must be managed to protect threatened species is not huge on Norfolk Island. Most of the vertebrate species on the island are highly dependent on the (460ha) Norfolk Island National Park. In fact the entire island is smaller than the combined area of Canberra Nature Park. Logistical challenges to threatened species conservation on the islands do not seem insurmountable.
A plan is in place
There is a comprehensive and recent threatened species recovery plan (2010) which outlines specific actions for 58 species listed under the EPBC Act. In addition, the main threats to the vertebrate biodiversity, specifically predation by rodents and cats, are well recognised in a number of threat abatement plans. Although Norfolk Island is not within any Natural Resource Management (NRM) region, there is an NRM plan that highlights threatened species actions and the potential for restoration of biodiversity.
A wealth of research and support is available for species recovery programs
There have been many decades of research and experience upon which threatened species recovery can be based. The rescue of the green parrot from near extinction and the last minute preservation of the local morepork genes through hybridisation with its close New Zealand relative are examples on Norfolk Island. The eradication of rabbits on Phillip Island, which led to the persistence of seabird colonies and gradual revegetation, is another.
There is also great opportunity to build on the efforts of islanders to become involved in restoration actions. Half of the endemic flora was on the verge of extinction in the 1980s: about 20 species were represented by populations of less than 20 individual plants. But as a result of education and encouragement, most species are now not only more common, but are used in local gardens and forest regeneration as the appreciation of their rarity has been understood by the community.
Low impact to industry
Finally, conservation of threatened species on Norfolk Island does not represent any major threat to commercial interests and in fact is likely to significantly benefit the main industry: tourism.
Virtually all of the conditions for successful recovery of threatened vertebrate species therefore seem to be in place and yet the decline of Norfolk Island species continues.
So why is Norfolk Island’s biodiversity still at such risk?
The Norfolk Island Natural Resource Management Plan (2009) offers a key insight: “the lack of cooperative and effective management of the environment”, a situation the authors noted had been evident since 2000.
Environmental management capacity on Norfolk Island, both within the Territory Government and Parks Australia, is extremely limited. As such, there is an inability to implement any more than a small fraction of the management actions as described in the Threatened Species Recovery Plan or NRM plan, including the protection of threatened species. Hopefully more focus on implementing these plans will occur as a result of the recent welcome news that the NRM ranger position on the island has now been filled, after being vacant for around a year.
“Basically, Norfolk Island’s biodiversity is just not on the radar,” -Dr Ray Nias
Almost no additional funding has been provided outside of the National Park operating budget for any threatened species conservation in recent years. In part this is a consequence of the limited capacity available to develop and submit proposals, but there are also significant administrative barriers that must be overcome.
Norfolk Island does not “fit” into the Australian NRM region system and therefore does not receive NRM baseline funding. The application process for Commonwealth environment funds is cumbersome and in most cases does not even recognise Norfolk Island as a region.
Perhaps worst of all is simple neglect. Norfolk Island, like the other Australian overseas territories, rarely if ever appears in Commonwealth Government environmental priorities, for example the recent ‘One Land – Many Stories: Prospectus of Investment or the Caring for our Country Target Area Grants.’
Basically, Norfolk Island’s biodiversity is just not on the radar. Until that is corrected, there will be no solution to the ongoing decline of biodiversity on Norfolk Island. Species such as the white-chested white-eye and the green parrot will simply disappear, unnoticed by the rest of Australia.
Brooke et al., 2007. Prioritizing the world’s islands for vertebrate-eradication programmes. Animal Conservation 10 (2007) 380–390.
About the author
Dr Ray Nias is the Director Southwest Pacific Region, Island Conservation. Island Conservation has received a grant from the Norman Wettenhall Foundation to continue the work of trying to overcome obstacles to biodiversity conservation and restoration on Norfolk Island.