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105
12
Back from the brink –
again: the decline and
recovery of the Norfolk
Islandgreen parrot
Luis Ortiz-Catedral, Raymond Nias,
JamesFitzsimons, Samantha Vine
and MargaretChristian
Summary
The problem
1. Shortage of nest sites for Nor folk Island green parrots safe from cat and rat
predation or competition with introduced birds.
2. Lack of intensive management of nest sites or monitoring to understand parrot
trends.
3. Nest boxes and protection of natural nest sites had been effective before in
recovering parrot numbers but the ongoing implementation of such measures
was neglected once the parrot had recovered from near extinction in 1988.
Actions taken to manage the problem
1. Based on an Action Plan developed for the Norfolk Island National Park in early
2013, and the appointment of a Natural Resource Manager, predator control
was enhanced including increased trapping of cats near parrot nests, revised
rodent baiting practices and culling introduced avian nest-competitors.
2. A population survey in mid-2013 confirmed the very small size of the
population. The survey was commissioned by non-government organisations
(NGOs) following concerns about the population being raised by local
residents in 2012.
3. Following the release of the 2013 survey results, the Australian Government
implemented an action plan that included expert training for national park
rangers to ensure reproductive output was maximised and plans for
establishment of an insurance population on predator-free Phillip Island.
Markers of success
1. Increasing parrot numbers.
Recovering Australian Threatened Species : A Book of Hope, edited by Stephen Garnett, et al., CSIRO PUBLISHING, 2018.
Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
Recovering Australian Threatened Species106
2. Renewed and ongoing commitment to maintenance of nest site maintenance
and protection.
3. Creation of a partnership between Parks Australia, the local community and
the NGO sector.
4. A forward-looking plan that identifies a durable solution.
Reasons for success
1. Resources available to rapidly commission population surveys.
2. Strong community interest in the parrot that meant that declines were
identified despite a lack of formal monitoring.
3. Existing knowledge of the actions needed to manage the parrot, and the
parrot’s high fecundity once adequate protection was provided.
4. Effective action by Nor folk Island National Park staff once the problem was
identified, working in partnership with external organisations.
5. An inclusive approach and targeted capacity development that resulted in
national park staff believing in the outcomes, having the skills to implement
recovery actions and able to take pride in their achievements.
Introduction
The Norfolk Island green parrot (Cyanoramphus cookii), also known as the Tasman para-
keet, is endemic to Norfolk Island, off eastern Australia. There have been two waves of
decline, near extinction, and managed recovery for this species: (1) decline and near
extinction from an early loss of habitat after settlement, combined with predation and
competition from introduced species (Hicks and Greenwood 1989; Hill 2002); (2) recovery
after 1988 following predator control and nest-protection; (3) decline again during the
period before 2013; and (4) recovery again, in 2014, after emergency intervention including
the predator proofing of suitable nesting sites.
The Norfolk Island green parrot is listed as Endangered under the federal Environment
Protection and Biodiversity Conservation Act 1999 (EPBC Act). Garnett et al. (2 011)
reviewed the conservation status of the Norfolk Island green parrot and considered it to be
Critically Endangered. The Norfolk Island green parrot is one of 20 bird species identified
in the Australian Government’s Threatened Species Strategy for priority attention (Aus-
tralian Government 2015).
A recovery plan for the species was released in 2002 (Hill 2002). The overall objective of
that plan was to shift the conservation status of the species from Endangered to Conserva-
tion Dependent within 10 years (Director of National Parks 2010). The single species
recovery plan was superseded in 2010 by the Norfolk Island Region Threatened Species
Recovery Plan (Director of National Parks 2010).
Conservation efforts for the Norfolk Island green parrot (Fig. 12.1A) provide numerous
lessons for threatened species recovery, ranging from the engagement of community, the
importance of monitoring, the danger of shifting emphasis from actions that were success-
ful, and the benefits of targeted surveys. They also highlight the importance of building
capacity within conservation staff in a remote location and of clear governance arrange-
ments to ensure good decision making and accountability.
Conservation management
The Norfolk Island green parrot was a common forest bird at the time of the discovery of
Norfolk Island in the late 1700s, but by the late 1970s the species had declined to fewer than
Recovering Australian Threatened Species : A Book of Hope, edited by Stephen Garnett, et al., CSIRO PUBLISHING, 2018.
Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
12 – Back from the brink – again: the decline and recovery of the Nor folk Islandgreen parrot 107
50 individuals (Silva 1989; Forshaw 2002). The main causes of decline included shooting
by early settlers, egg and chick depredation by introduced rats and cats and shortage of
safe nesting sites (hollows and cavities) owing to felling of large trees since the early 1800s
(Hermes 1985; Hicks and Greenwood 1989). Further pressures on declining parrots
included competition for nesting sites by the introduced crimson rosella (Platycercus ele-
gans) and common starling (Sturnus vulgaris) (Forshaw 2002). Efforts to reverse the decline
of the species commenced in 1983 when the Government Conservator oversaw the con-
struction of a captive breeding aviary. The captive breeding program failed to fledge suf-
ficient chicks to aid in the recovery program, but succeeded in building local engagement
and nurturing a sense of stewardship in the local community.
In 1987–1988, the staff from Norfolk Island National Park officially began rat and cat
control operations on Mount Pitt (cat trapping occurred unofficially before the park was
declared) and provisioning of purpose-built nesting sites and regular monitoring (Hicks
and Greenwood 1989). The Norfolk Island green parrot nests in tree hollows and these can
be modified to prevent rats from gaining access to the nest. From 1987 to the early 2000s,
~250 chicks fledged successfully as a result of the nest-provisioning and predator-control
programs. Sightings of green parrots in the National Park and nearby orchards and gar-
dens became more common. However, after that time changes in the management of the
Fig. 12.1. (A) This male Nor folk Island green parrot fledged from the first active predator-proofed
nest located in July 2013 and had already paired with an adult female by the time of the photograph
4 months later. (B) The parrot s are well camouflaged while foraging in red guava (Psidium cattleianum),
highlighting the importance of targeted surveys (photos: Luis Ortiz-Catedral).
Recovering Australian Threatened Species : A Book of Hope, edited by Stephen Garnett, et al., CSIRO PUBLISHING, 2018.
Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
Recovering Australian Threatened Species108
Norfolk Island National Park resulted in a shift in emphasis away from specific manage-
ment of the parrot population to habitat rehabilitation activities that were stated to be of
benefit to all native species.
Concern over the status of the green parrot, was raised again in 2009–2012 by natural-
ists on the Island (e.g. in Garnett et al. 2011). A survey of forest birds in 2009, funded by
BirdLife International, detected parrots at a few survey locations and estimated a popula-
tion of ~240 birds (Dutson 2013). The study also highlighted the need for a targeted survey
of green parrots due to the challenge of estimating actual numbers with an acceptable
confidence interval (Fig. 12.1B). Despite these concerns and those of local naturalists, the
National Park Manager and Canberra-based officials at the time stated in late 2012 there
was no evidence for, nor any reason to suspect, a recent decline. In response, the Norfolk
Island Flora and Fauna Society, Island Conservation, BirdLife Australia and The Nature
Conservancy commissioned an expert in the Cyanoramphus genus (Luis Ortiz-Catedral
from Massey University) to undertake a targeted population survey (Fig. 12.2A).
A new Natural Resource Manager was appointed in April 2013 and this bought con-
siderable additional expertise to the National Park. An interim Action Plan was devel-
oped for the parrot and a small grant to re-construct some of the old nest sites was secured
in May 2013.
The first targeted survey for Norfolk Island green parrots since the 1990s was com-
pleted over 25 days in July–August 2013. Mapping of all visual and acoustic records
obtained during 220h of searches along 282km of transects by two observers with 5–10
years’ experience of Cyanoramphus parrots, revealed that only between 42 and 96 indi-
viduals survived, with only 10 confirmed adult females in ~300 ha of remnant forest
(Ortiz-Catedral 2013). Although it is unclear when population declines started, it appears
it was linked to nest deterioration and possibly a lack of intense rat and cat control around
active nesting sites and throughout the National Park. Out of the 72 nests available by the
late 1990s, only 12 were deemed suitable in late 2013. This prompted and enabled an emer-
gency program targeting the shortage of safe nesting sites.
In November 2013, the combined NGOs wrote to the Federal Minister for the Environ-
ment, the Hon. Greg Hunt MP, with the findings of this survey and a list of urgent recom-
mendations. This was followed by a series of meetings with ministerial staff and department
officials highlighting the urgency of the situation and the feasibility of solutions. In
December 2013, a response was received indicating that the Minister had accepted the
findings and agreed to implement a comprehensive recovery effort. Within 12 months, 78
rat and cat-proof nests were built and rat and cat control intensified in the immediate
vicinity of these nests. These actions resulted in 13 active nests, which successfully fledged
chicks by May 2014 (Mi l man 2014). Regular monitoring of the green parrot population
revealed an increase in sightings by June 2015, when the population had increased to ~220
individuals as estimated by DISTANCE surveys (Skirrow and Ortiz-Catedral unpub-
lished). This increase is better explained as pulses of juvenile birds resulting from the
assisted nesting program, rather than steady recruitment. In support of this view, periodic
declines in population estimates are still detected. For instance, in March 2015, a popula-
tion of 144 was estimated using the same methodology. The measurable increase in the
population of the species is supported by a significant six-fold increase in detection rates:
from 0.74 detections per hour in July 2013, to 4.22 detections per hour in June 2015. In
addition, mapping of records indicates the presence of breeding pairs in previously unoc-
cupied areas. However, the proportion of juveniles recruiting into the breeding population
is still under investigation (Ortiz-Catedral unpublished).
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12 – Back from the brink – again: the decline and recovery of the Nor folk Islandgreen parrot 10 9
On average, nest success (i.e. nests where at least one chick fledged; Fig. 12.2A) is 70% by
the 2016 breeding season. In contrast, during most of its management, green parrot nest
success has rarely exceeded 40%. Thus, with the current management, more nests are suc-
cessful and more chicks produced per nest and per year as a result of providing new or safer
nests (Fig. 12.2B) and improved ranger capacity to monitor nests without disturbance.
Research, biology and identification of key threats
The Norfolk Island green parrot, like other Cyanoramphus species, has high reproductive
potential, laying large clutches of up to eight eggs (Forshaw 2002). The species also reaches
sexual maturity at a relatively early age, making it possible for juveniles to begin nesting
within months of fledging. This makes the species a useful indicator of the effectiveness of
management actions, because a positive effect would be reflected in parrot numbers and
breeding activities in a relatively short time and over a small area: Norfolk Island green
parrots inhabit a core forest remnant of ~300ha (Fig. 12.3).
The key threats to the species are well known (predation and competition for nest hol-
lows). Thus providing safe nesting sites proved to be an effective way to boost the popula-
tion and resulted in a detectable increase in breeding pairs from 10 confirmed breeding
pairs in 2013 to ~22 pairs in 2014. At least four breeding pairs observed in 2014 involved
juvenile females, most likely hatched in the preceding 8months.
Fig. 12.2. (A) Luis Ortiz-Catedral measuring a fledgling Norfolk Island green parrot. Males and
females can be distinguished before fledging by the dimensions of their bills. (B) Joel Christian
inspecting a nest cavity protected from climbing rats and cats by the smooth cement surface
surrounding the cavity entrance (photos: A, Mark Delaney, B, Luis Ortiz-Catedral).
Recovering Australian Threatened Species : A Book of Hope, edited by Stephen Garnett, et al., CSIRO PUBLISHING, 2018.
Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
Recovering Australian Threatened Species11 0
Planning and policy
A Norfolk Island Green Parrot Recovery Plan was in place and resourced from 2002 (Hill
2002) but replaced in 2010 by the multispecies Norfolk Island Region Threatened Species
Recovery Plan (Director of National Parks 2010). Despite a new plan being in place, the
species’ population continued to decline and key components of the previous 2002 Recov-
ery Plan, which were known to be successful, including maintenance of ‘rodent-proof’
nesting sites had ceased by 2013. When the recovery efforts re-commenced in earnest in
2014, it again focused on these proven successful strategies.
People, agencies, governance, and accountability
Before the Australian Government’s involvement in Norfolk Island’s environmental issues
from 1979, the late Owen Evans monitored a range of bird species, the island’s flora and
other terrestrial biota, raising the alarm and taking remedial action. The island’s early Gov-
ernment Conservators took ecological advice from Evans and he influenced the direction
for management plans. Neil Hermes, the second Conservator, instigated the actions that
began recovery of several bird species, including the green parrot. Locally appointed staff
carried a strong sense of responsibility and ownership, with the community remaining
involved and interested, as they had been encouraged to be over the years by Evans. Despite
changes in the Norfolk Island National Park managers, with their differing approaches, the
consistency that local staff and a strong, passionate, hands-on Advisory Committee brought,
provided continuity and purposeful, outcome-oriented management.
Policy changes saw a formal shift in emphasis from single species to multi-species
recovery approaches and broad-scale threatening processes. As good news stories had
been written about the success of the green parrot program, there seemed to be no need
to protect an already ‘saved’ species, and the budget became consumed by competing
priorities. Local naturalists raised concerns regarding the population size and trajectory
with the Australian Government in 2010 (reflected in Garnett et al. 2011) and with Aus-
tralian non-government conservation groups in 2012. By March 2013, in a meeting with
the concerned NGOs, the Department acknowledged the value of developing a robust,
Fig. 12.3. Distribution of Nor folk Island green parrots on Norfolk Island in Oct– Nov 2013 and
Aug–Sept 2016.
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Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
12 – Back from the brink – again: the decline and recovery of the Nor folk Islandgreen parrot 111
repeatable methodology for determining a reliable figure for the population of green
parrots in the Park.
The independently NGO-commissioned 2013 surveys allowed much flexibility with
how the findings could be communicated both to government and the general public. Arti-
cles in birding magazines on the dire state of the species alerted bird interest groups while
media was used by the partners to communicate the message to the general public. We also
ensured the results and straightforward solutions were rapidly communicated to the Aus-
tralian Government. Because the majority of the green parrot’s habitat occurred in Norfolk
Island National Park (a park managed by the Australian Government), there was a more
direct responsibility here for the Australian Government than for most other Australian
threatened species. We were conscious that the most recent vertebrate extinction to that
date (the Christmas Island pipistrelle) had occurred in another Australian Territory, and
that the imminent loss of another species from a Commonwealth-managed territory would
want to be avoided by the Australian Government.
Managing
Management actions were influenced through a combination of expertise, local knowl-
edge and public support and the ability to access money to commission new science rela-
tively quickly. In our discussion with the management agencies in early 2014, we came to
agreement that the management actions that had worked in the past were the ones again
that needed to be implemented immediately, or significantly enhanced (such as predator-
proofing of nest-sites; Fig. 12.2B). Other actions, such as translocating an insurance popu-
lation to nearby Phillip Island following methods developed in other Cyanoramphus
species in New Zealand (Ortiz-Catedral and Brunton 2010) could be undertaken once the
immediate extinction crisis had been averted. The historical range of green parrot most
likely included Phillip Island, because previous accounts of that site describe a similar
composition of plant species to areas near Mount Pitt (Coyne 2009) and because Phillip
Island is within the flying capabilities of Cyanoramphus parrots (Ortiz-Catedral 2010).
An outcome of this engagement, and a shared understanding of the issues and appropri-
ate management responses, has seen a strong and productive relationship formed between
various stakeholders. Not only do the recovery actions continue to proceed, an advisory
group has been formed with stakeholder representatives, new partners (e.g. WildMob) have
come to the scene with additional resources and new actions have been developed that may
not have otherwise been possible. One example of this has been the development by the
local community and Norfolk Island National Park of an integrated rodent-control pro-
gram covering private properties in the Anson Bay areas, the adjacent Forestry Zone and
the National Park. The aim is to increase the area of Norfolk Island under effective predator
control, creating additional safe habitat for the expanding green parrot population.
Monitoring
Surveys of Norfolk Island green parrots have continued every 4–6 months by volunteers
and staff from the Norfolk Island National Park to determine population trends. Over the
last 3 years, two monitoring approaches have been used: visual and acoustic detections
along visitor tracks and DISTANCE sampling on 60–80 random locations. The latter,
although more labour intensive, has yielded the most consistent results.
Infrastructure and technology
A key aspect of the recovery of the Norfolk Island green parrot has been provisioning of
safe nesting sites combined with intense rat and cat control around active nests. The
Recovering Australian Threatened Species : A Book of Hope, edited by Stephen Garnett, et al., CSIRO PUBLISHING, 2018.
Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
Recovering Australian Threatened Species112
development of a protocol for nest checking without disturbing nesting females (which
might lower hatching success and hence reproductive output) has also been important. To
prevent nest desertion or altering the duration of incubating stints, the contents of active
nests are checked weekly and only after males call females out of the nest to feed them.
These incubating or brooding ‘breaks’ occur roughly every 2–4h, and last for 10–25 min.
This behaviour is stereotypical of Cyanoramphus parrots and stops when chicks are ~2–3
weeks old (Ortiz-Catedral 2006).
Money
Seed funding for first surveys and diagnosis of the problem came from The Nature Con-
servancy’s Ecological Science Program (supported by The Thomas Foundation) and
through grants to Island Conservation from the Norman Wettenhall Foundation and
Packard Foundation, the Mohamed bin Zayed Species Conservation Fund, WildMob,
Massey University, The World Parrot Trust and Parrot Society UK. This equated to
~A$90000. Funding of A$50000 to the Norfolk Island Flora & Fauna Society from the
Australian Government’s Caring for our Country Program in 2013–2014 also allowed the
society to highlight several issues relating to the species during ‘Invasive Species Month’.
Grants of A$27500 to the Norfolk Island National Park from the Foundation for National
Parks and Wildlife and the Parrot Society of Australia allowed construction of 78 rat and cat-
safe nests and kick-start a pilot study on the movements and survival of fledglings.
In-kind support provided by volunteers from WildMob has an additional estimated
value of around A$50000 at late 2016.
The operating cost for the Norfolk Island National Park and Botanic Garden was
A$1.183million in 2014–2015 (Director of National Parks 2015), although it is not speci-
fied how much was allocated to actions that directly targeted to the Norfolk Island green
parrot. The Threatened Species Commissioner (2015) committed A$300000 of Australian
Government funding in 2015 for rodent control on Norfolk Island to benefit several spe-
cies, including the green parrot.
The future
Emergency actions started in 2013 have made it possible to increase the numbers of green
parrots within the Norfolk Island National Park and strengthen the capacity of the park
staff to manage the species. As long as rodents exist on Norfolk Island, there will be an
ongoing need to maintain a vigilant effort to control their numbers and to provide suffi-
cient predator-proof nest-sites for an expanding population of parrots. Maintaining ade-
quate and ongoing funding to essential management activities, such as rat and cat control
and nest hollow maintenance, will be critical into the future.
However, the species is still restricted to a single breeding population. Experience with
other Cyanoramphus parrots in New Zealand show that translocation to predator-free sites
is an effective measure to increase the number of populations and individuals (Ortiz-Cat-
edral and Brunton 2010). Thus, the next milestone in the conservation of the species is to
establish a population on rodent-free Phillip Island that should provide a valuable insur-
ance population in case of extreme events such as disease outbreaks or major habitat loss.
Significant resources will need to be sourced for this proposal and in 2017, more than A$86
000 was raised for the translocation through a crowdfunding campaign (Jeffery 2017).
No formal recovery team existed at the time of writing, but a recovery team with inde-
pendent representatives would provide an important governance structure that can
Recovering Australian Threatened Species : A Book of Hope, edited by Stephen Garnett, et al., CSIRO PUBLISHING, 2018.
Copyright © 2018. CSIRO PUBLISHING. All rights reserved.
12 – Back from the brink – again: the decline and recovery of the Nor folk Islandgreen parrot 113
weather the vagrancies of changing government priorities and provide a mechanism that
can respond to changes in the parrot’s status if necessary. The Recovery Plan is due for
review and revision to guide future recovery effort.
Conclusions
The ongoing success of recovery for the Norfolk Island green parrot will build upon and
rely on the ongoing collaboration between the key players and the management structures
established by the Norfolk Island National Park. The ultimate recovery of the Norfolk
Island green parrot will always remain at risk so long as invasive predators and competi-
tors remain in large numbers on Norfolk Island. For the foreseeable future, the fate of the
species will require careful monitoring and active management to reduce threats from
invasive species.
Acknowledgements
The success in the conservation of the Norfolk Island green parrot has been possible
thanks to the logistical and financial support of: Massey University; Mohamed bin Zayed
Species Conservation Fund; World Parrot Trust; The Parrot Society, UK; Norfolk Island
Flora & Fauna Society; WildMob; Island Conservation; The Packard Foundation; The
Nature Conservancy’s Ecological Science Program generously funded by The Thomas
Foundation; BirdLife Australia; Auckland Zoo Conservation Fund; Australian Govern-
ment’s Department of the Environment and Energy; Foundation for Parks and Wildlife
Australia; The Parrot Society of Australia. Alan Saunders, Guy Dutson and Derek Ball
provided expert input. Special thanks to the staff from the Norfolk Island National Park:
Craig Doolan, Joel Christian, Ken Christian, Dids Evans, Rossco Quintal, Abigail Smith,
Matt King and Cassandra Jones. Volunteers Liz Whitwell, Matt Upton, Daniel Waldmann,
Luke Martin, Emma Wells, Nat Sullivan, Tansy Bliss, Rebecca Hamner, John Steemson,
Amy Waldmann, Mike Skirrow and Jessica Barr provided assistance in the field. Derek
Greenwood, Beryl Evans, Dave South and Rob Ward shared their knowledge about green
parrots, and people of Norfolk Island have welcomed us in their community. Aaron
Harmer developed the basis for the map. Craig Doolan, Judy West, Peter Latch and Ste-
phen Garnett commented on an earlier draft of the chapter.
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