Environment Protection and Biodiversity Conservation (Norfolk Island Region Threatened Species Recovery Plan) Instrument 2025

I, Tanya Plibersek, the Minister for the Environment and Water, make the Norfolk Island Region Threatened Species Recovery Plan in the following instrument.

Dated 13.2.25

Tanya Plibersek

Minister for the Environment and Water

1  Name

  This instrument is the Environment Protection and Biodiversity Conservation (Norfolk Island Region Threatened Species Recovery Plan) Instrument 2025.

2  Commencement

  This instrument commences on the day after it is registered.

3  Authority

  This instrument is made under subsection 269A(2) of the Environment Protection and Biodiversity Conservation Act 1999.

© Commonwealth of Australia 2025

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Cataloguing data

Citation details: Commonwealth of Australia (2025) Norfolk Island Region Threatened Species Recovery Plan. Department of Climate Change, Energy, the Environment and Water, Canberra.

This publication is available at SPRAT EPBC Act Recovery Plans.

Department of Climate Change, Energy, the Environment and Water

GPO Box 3090 Canberra ACT 2601

Telephone 1800 803 772

Web dcceew.gov.au

Disclaimer

The Australian Government acting through the Department of Climate Change, Energy, the Environment and Water has exercised due care and skill in preparing and compiling the information and data in this publication. Notwithstanding, the Department of Climate Change, Energy, the Environment and Water, its employees and advisers disclaim all liability, including liability for negligence and for any loss, damage, injury, expense or cost incurred by any person as a result of accessing, using or relying on any of the information or data in this publication to the maximum extent permitted by law.

This Recovery Plan has been developed with the involvement and cooperation of a range of stakeholders, but individual stakeholders have not necessarily committed to undertaking specific actions. The achievement of targets and the provision of funds may be subject to budgetary and other constraints and may also be constrained by the need to address other conservation priorities. Approved recovery actions may be subject to modification due to changes in knowledge and changes in conservation status.

Acknowledgement of Country

We acknowledge the Traditional Custodians of Australia and their continuing connection to land and sea, waters, environment and community. We pay our respects to the Traditional Custodians of the lands we live and work on, their culture, and their Elders past and present.

Contributions

Lead authors and editors: Nicholas Macgregor, Margarita Goumas, Jess Williams, Erik Doerr, Samuel Merson, Carla Miles, Alyssa Roggero, Lil Blake, Melinda Wilson, Allie Andersen, Grace Wall, Lydia Ayto.

Contributors: Keith Broome, Rhonda Butcher, Nicholas Carlile, James Castles, Joel Christian, Margaret Christian, Rohan Clarke, Department of Infrastructure, Transport, Regional Development, Communications and the Arts, Eloise Dowd, Daniel Gautschi, Simon Gorta, Nigel Greenup, Frances Greeshaw, Luke Halpin, Marc Hockings, Ben Hoffman, Isabel Hyman, Salit Kark, Lilli King, Peter Latch, Juliana Lazzari, Glynn Maynard, Kevin Mills, Penny Olsen, Luis Ortiz-Catedral, Tara Patel, Julie Quinn, Philip Reid, Libby Rumpff, Bec Rush, Mitch Ryan, Mark Scott, Flossy Sperring, Hannah Taylor, James Tweed, Gillian Walker, James Watson, Chuanji Yong, Heidi Zimmer.

We also acknowledge the members of Threatened Species Scientific Committee who provided insightful and valuable feedback during the preparation of this plan, and we thank them for their contributions.

This plan represents the combined efforts of many people, including those who have directly contributed to the content of the plan and those who have built the knowledge and understanding on which the plan relies.

Image credits

Cover: Kermadec petrel (credit: Stuart Cohen); White oak flowers (credit: Parks Australia); Phillip Island aerial image (credit: Norfolk Island Tourism); Norfolk Island green parrot (credit: Parks Australia).

Page iv: Norfolk Island landscape (credit: Norfolk Island Tourism).

Contents

Summary...................................................................1

Purpose................................................................1

Summary of targets........................................................1

Summary of recommended management and monitoring............................6

Summary of the costing framework............................................7

Part 1—Context..............................................................9

1.1 Introduction.......................................................9

1.2 The Norfolk Island Group.............................................17

Part 2—Pressures and risks....................................................66

2.1 Pressures.........................................................66

2.2 Risk assessment....................................................79

Part 3—Review of past planning and management...................................85

3.1 Review of implementation of the previous recovery plan......................85

3.2 Analysis of the adequacy of current management...........................96

Part 4—Management planning..................................................99

4.1 Conceptual framework for management planning...........................99

4.2 Ten-year species targets.............................................103

4.3 Ten-year management targets........................................107

4.4 Direct management programs.........................................109

4.5 Supporting management actions.......................................119

4.6 Adaptive management..............................................122

4.7 Research........................................................127

Part 5—Implementation......................................................130

5.1 Governance and responsibilities.......................................130

5.2 Interaction with other plans, policies, and strategies........................142

5.3 Costs of implementation.............................................144

5.4 Implementation timeframe...........................................151

Part 6—Species profiles......................................................152

6.1 Invertebrates.....................................................155

6.2 Reptiles.........................................................172

6.3 Land birds.......................................................180

6.4 Seabirds........................................................202

6.5 Flora...........................................................239

Part 7—Appendices.........................................................389

Appendix A: Conceptual models.............................................390

Glossary..............................................................395

References............................................................397

Tables

Table 1 Ten-year targets for animal species..........................................2

Table 2 Ten-year targets for plant species...........................................3

Table 3 Ten-year management targets.............................................5

Table 4 Listed threatened species covered by the recovery plan..........................11

Table 5 Soils of Norfolk Island...................................................20

Table 6 EPBC listed threatened molluscs of the Norfolk Island Group.......................24

Table 7 EPBC listed threatened reptiles of the Norfolk Island Group.......................27

Table 8 Endemic and/or EPBC listed avian fauna of the Norfolk Island Group.................29

Table 9 Distribution of EPBC listed threatened fauna (excluding species presumed to be extinct) on the Norfolk Island Group across tenure types......42

Table 10 Threatened and/or endemic plants of the Norfolk Island Group....................43

Table 11 Distribution of EPBC listed plant species of the Norfolk Island Group across tenure types.47

Table 12 Description of the native plant communities found on Norfolk Island and a summary of the threatened plant species that may occur within them......52

Table 13 Plant communities of Phillip Island.........................................54

Table 14 Area of native plant communities (remnant and non-remnant) on Norfolk Island predicted for 1750 and estimated for 2020, and percentage remaining in 2020......58

Table 15 Distribution of remnant plant communities present in 2020 on Norfolk Island across tenure types......59

Table 16 Sites of significant native vegetation in the Norfolk Island Group, including in the national park, public reserves and other locations......61

Table 17 Key threatening processes listed under the EPBC Act relevant to Norfolk Island Group...76

Table 18 Potential weed species of concern in the Norfolk Island Group....................77

Table 19 Risk matrix used to assess risks to species...................................80

Table 20 Summary of severity of risk posed by each pressure to each species................81

Table 21 Species population estimates and trends from 2010 to 2023......................90

Table 22 Summary of actions completed...........................................94

Table 23 Management programs assessed..........................................96

Table 24 IUCN status definitions.................................................97

Table 25 IUCN rules for assigning status............................................97

Table 26 Listed threatened fauna species and their 2034 targets.........................103

Table 27 Listed threatened plant species and their 2034 targets.........................105

Table 28 Management targets and the pressures they address..........................107

Table 29 Management programs and associated targets and actions to achieve 2034 targets for threatened species......110

Table 30 The importance of each management program for each species..................115

Table 31 Summary of roles in delivering the plan—direct management....................140

Table 32 Summary of roles in delivering the plan—supporting management, research and monitoring141

Table 33 Core and contingent management programs, and their locations of implementation, for which costs have been estimated......146

Table 34 Estimated cost of management programs over five years for Norfolk Island National Park, public reserves and other land......148

Table 35 Five-year present value cost of management programs by activity category and area...150

Figures

Figure 1 Sequence of management programs and targets over the life of the plan..............2

Figure 2 Photos of the native plant communities on Norfolk Island........................51

Figure 3 Predicted response after 10 years under 2021 management levels..................98

Figure 4 Simplified conceptual model of the pressures, drivers, and management that influence the state of threatened species on the Norfolk Island Group......99

Figure 5 The hierarchy of outcomes relevant to this ten-year plan........................102

Figure 6 Illustration of the major steps of the adaptive management cycle and its links to the Norfolk Island Region Threatened Species Recovery Plan......122

Figure 7 An example of a chain of linked indicators, representing the monitoring of a sequence of results towards a final target for a threatened species......123

Figure 8 Schematic overview of a possible integrated monitoring program to comprehensively track results across major management programs......124

Figure 9 A conceptual overview of evaluation across sets of linked resource, management, pressure and value indicators, and some of the management decisions that might be considered under different scenarios......125

Figure 10 Conceptual model of factors and interactions influencing forest birds on Norfolk Island..390

Figure 11 Conceptual model of factors and interactions influencing native plant communities and threatened plant species on Norfolk Island......391

Figure 12 Conceptual model of factors and interactions influencing threatened snails on Norfolk Island......392

Figure 13 Conceptual model of factors and interactions influencing native plant communities and threatened plant species on Phillip Island......393

Figure 14 Conceptual model of factors and interactions influencing threatened animals on Phillip Island......394

Maps

Map 1 Terrestrial areas of the Norfolk Island Group covered in the plan, including location of protected areas......10

Map 2 Soil map of Norfolk Island.................................................19

Map 3 A Map showing the known locations of threatened molluscs on the Norfolk Island Group..35

Map 4 A map showing the distribution of threatened reptiles on the Norfolk Island Group.......36

Map 5 Primary distribution of the Norfolk Island green parrot...........................37

Map 6 Range movements of the Norfolk Island morepork on Norfolk Island.................38

Map 7 Distribution of the Norfolk Island golden whistler...............................39

Map 8 Distribution of the Norfolk Island robin.......................................40

Map 9 Distribution of the Kermadec petrel in the Norfolk Island Group.....................41

Map 10 Number of threatened plant species in each park and reserve in the Norfolk Island Group.46

Map 11 Norfolk Island native plant communities present in 1750.........................56

Map 12 Norfolk Island native plant communities present in 2020.........................57

Summary

Purpose

The purpose of the Norfolk Island Region Threatened Species Recovery Plan (‘the plan’) is to provide the management and supporting actions necessary to stop the decline and support the recovery of terrestrial threatened species in the Norfolk Island Group. By taking a regional approach, this plan seeks to identify and support integrated solutions for the threatened species in the Norfolk Island Group and contribute to conservation of overall biodiversity on the islands. The plan covers all land tenures across the Norfolk Island Group including Norfolk Island, Phillip Island, Nepean Island and surrounding rock stacks (Map 1) but does not address the Norfolk Marine Park, which is managed under the Temperate East Marine Parks Network Management Plan 2018 (Director of National Parks 2018). The plan replaces the previous Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks 2010).

The plan serves as a formal recovery plan for a specific subset of the threatened species in the Norfolk Island Group, comprising 46 plant species, five bird species and two reptile species (Table 1). It also includes actions for five endemic snails that are listed under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), but which do not require a recovery plan.

Successful implementation of the plan requires coordination by a recovery team made up of agencies with responsibility for land management and other stakeholders, with strong participation by the Norfolk Island community.

Summary of targets

The plan contains a detailed conceptual framework for management planning based on a hierarchy of outcomes. A long-term vision and goals provide a direction of travel, recognising that the plan is one part of an ongoing process to restore the Norfolk Island Group’s biodiversity and ecosystems. Within that context, the plan focuses on a sequence of specific aims for the next ten years, based on delivery of management actions (grouped into management programs), leading to achievement of management targets, in turn leading to achievement of recovery targets for the species (Figure 1). Targets have been set to be sufficiently ambitious to support achieving the vision for 2050 while being achievable within a decade if sufficient resources are available.

Details of each of those three levels of targets are summarised below (with full details in Part 4—Management planning). They are presented in the reverse of the order in Figure 1, on the basis that planning starts with defining desired outcomes and works back to identify relevant intermediate targets and required actions.

Figure 1 Sequence of management programs and targets over the life of the plan

Ten-year species targets

Summary tables of animal and plant species targets are below. For full details, see Table 26 and Table 27.

Table 1 Ten-year targets for animal species

Table 2 Ten-year targets for plant species

a Target figures refer to number of individuals, unless otherwise stated.

Ten-year management targets

A summary table of management targets is below. For full details, see Table 28.

Table 3 Ten-year management targets

a See risk assessment at Section 2.2

Summary of recommended management and monitoring

A coordinated suite of management programs will be required to achieve the objectives of the plan, including:

• biosecurity
• integrated invasive animal control:
• control of rodents
• control of feral chickens
• control of free-roaming cats
• control of crimson rosellas
• control of swamphens
• eradication of Argentine ants
• control of Phytophthora cinnamomi
• restoration of native vegetation
• fire management
• provision of nest sites for native threatened birds
• population management.

See Table 3 for a summary and Table 29 for full details of these management programs.

Direct management must be supported by a range of supporting actions, including coordination, policy and legislation, and community engagement and communication.

It is essential that management is informed by a comprehensive and integrated program of monitoring and evaluation. Section 4.6 (Adaptive management) provides a framework for developing a monitoring plan with the ability to track results across chains of linked indicators, representing a sequence of results towards a final goal, specifically regarding: (1) investment of resources, (2) delivered management actions, (3) state of pressures (relating to management targets) and (4) populations of threatened species (relating to species targets). Regular evaluation across these chains of indicators will enable progress to be tracked and appropriate adaptive adjustments to be made to management, ecological monitoring, and research elements of the recovery plan.

Summary of the costing framework

The plan applies a systematic costing framework to estimate the budget that would be required to achieve the targets of the plan and help secure the long-term future of the unique biodiversity of the Norfolk Island Group. Costs were estimated for all core and contingency management programs. For each program, the underlying activities required to achieve the management target over a five-year period were identified, using a standardised framework of categories of activity and different cost components. Structured models were used to estimate the costs of each management program, including simulating a range of cost estimates to account for uncertain variables such as travel and labour costs. Contingency costs for eradicating invasive species from Phillip Island if those species arrived on the island from Norfolk Island were estimated by considering the per eradication event cost and the probability of occurrence over the five years.

Costs were estimated separately for three management areas: Norfolk Island National Park, public reserves, and other land. Table 33 summarises the management programs and locations to which they apply.

Estimates of total costs over five years (best estimates with ranges to incorporate uncertainty in cost predictions) are:

• Norfolk Island National Park: $54,217,963 (range: $39,235,600 to $82,376,763)
• public reserves: $16,551,581 (range: $11,922,670 to $25,470,962)
• other land: $13,884,341 (range: $9,534,594 to $21,314,373).

Approximately 64% of costs would be associated with management in the national park, 20% with management in public reserves and 16% with management on other land (Table 34). This reflects the size of the park relative to public reserves, and the wider ranging and/or more ambitious management targets that have been set for the park in comparison with other types of land.

Of the different programs, restoration of native vegetation was estimated to be the most resource intensive, representing over 50% of the total budget. Rodent control was the next most expensive ongoing program, at 15% of the total.

The bulk of costs identified are for on-ground management (78.5% of the total), but resources will also be required for other actions, including planning and coordination, monitoring, research, education and training.

The cost figures are estimates of what it would cost to fully implement the plan. They do not indicate the budget that will be available; nor do they represent a commitment by any organisation to provide any element of the budget. Relevant organisations should use this plan to prioritise actions to protect species and enhance their recovery.

Structure of the plan

This plan is presented in seven parts.

Part 1 presents the purpose and scope, the legislative context, and a description of the Norfolk Island Group, including an introduction to the threatened species addressed in this plan.

Part 2 outlines the past, current and likely future pressures on threatened species and biodiversity in the Norfolk Island Group and presents an assessment of risks associated with those pressures.

Part 3 presents the results of a review of the previous recovery plan and an analysis of the adequacy of management that was being undertaken in 2021 when development of the new plan began.

Part 4 covers the logic and conceptual underpinning of the plan, management planning, including the species and management targets for the next ten years, and the management programs and actions to be implemented to achieve those targets.

Part 5 covers implementation, including governance, and a summary of the methods and results of an analysis to estimate the costs of delivering the plan.

Part 6 contains detailed species profiles for each of the threatened species, including a summary of the actions outlined in this plan to guide their management. Profiles are also included for some of the region’s most significant seabirds, some of which are listed as marine and/or migratory under the EPBC Act.

Part 7 provides additional information in Appendices.

Part 1—Context

1.1         Introduction

1.1.1        Purpose and scope

The Norfolk Island Group contains many threatened species in a relatively small and isolated geographic area. Many of the threatened species in the Norfolk Island Group are affected by common pressures and have overlapping requirements. To take a more strategic and integrated approach to threatened species recovery and threat abatement for the Norfolk Island Group, a regional recovery plan is more appropriate than separate plans for individual species. This allows for more integration of regional scale threat abatement activities, and many of the management actions proposed have been devised to deliver benefit to multiple species.

The recovery plan replaces the previous Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks 2010). The overall objective of the previous recovery plan was to secure and improve the conservation status of Norfolk Island threatened species through an integrated program of habitat protection and improvement, threat abatement, and public awareness and involvement. The previous plan covered 58 threatened species, serving as a formal recovery plan for 53 of these. The plan also provided conservation actions for five endemic snails that are listed under the EPBC Act, but which do not require a recovery plan (there is an additional conservation advice in place for each of the five species).

The purpose of this recovery plan is to outline the management and recovery actions necessary to stop the decline and support the recovery of terrestrial threatened species on Norfolk Island. This plan aims to maximise the likelihood of threatened species surviving long term in the wild and is intended as the next phase of a longer pathway towards the conservation of biodiversity on Norfolk Island. By taking a regional approach, this plan seeks to identify and support integrated solutions for the group of threatened species, ecosystems, and general biodiversity in the Norfolk Island Group. However, within that broad scope it is essential to identify and address the management and recovery requirements of the individual species and to identify the priority actions to be delivered in different places. This balance is reflected in the targets that have been established.

The plan covers all land tenures across the Norfolk Island Group including Norfolk Island, Phillip Island, Nepean Island and surrounding rock stacks (Map 1) but does not address the Norfolk Marine Park (which is managed under the Temperate East Marine Parks Network Management Plan 2018 (Director of National Parks 2018). However, there are important ecological interactions between seabirds and other primarily land-dwelling species with the surrounding marine environment. Where necessary, these interactions are acknowledged, and the Norfolk Marine Park is discussed briefly in section 5.1.

Map 1 Terrestrial areas of the Norfolk Island Group covered in the plan, including location of protected areas

The plan covers all land tenures across the Norfolk Island Group including Norfolk Island, Phillip Island, Nepean Island and surrounding rock stacks, but does not address the Norfolk Marine Park.

The plan is formally made for 53 threatened species in the Norfolk Island Group that are listed under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), but more broadly addresses the full suite of threatened species, comprising 46 plant species, five species of land snails, five bird species and two reptile species (Table 4). This plan is consistent with, or will not conflict with, any other recovery plans for species that are in force under the EPBC Act. This plan will serve as a formal recovery plan under the EPBC Act for all species listed in Table 4 with the exception of the five molluscs, which do not formally require a recovery plan under the EPBC Act and have a conservation advice in place. The five snail species all occur in areas currently managed as national parks or public reserves, and the approved conservation advices are considered sufficient for providing direction to implement priority actions and manage key threats.

Note that for taxonomic names of the threatened species covered by this plan, all scientific names used are those for the species as they are currently accepted by the Australian Plant Census (APC) for flora and the Australian Faunal Directory (AFD) for fauna. Where species have been listed under the EPBC Act under previous names, the listed name appears first in tables, with the APC/AFD name in brackets, and any further information provided in table notes.

Table 4 Listed threatened species covered by the recovery plan

a Hyman et al. (2023) have completed a revised taxonomy of the Norfolk Island microcystid snails and concluded that the three genera, Advena, Mathewsoconcha and Quintalia, should be combined into the single genus Advena. However, these recommendations are yet to be adopted by the Australian Faunal Directory.

b Listed under the EPBC Act as Lastreopsis calantha. The Australian Plant Census (APC) accepts Lastreopsis calantha and recognises Parapolystichum calanthum as a synonym.

c Listed under the EPBC Act as Marattia salicina. The APC accepts the name Ptisana salicina and recognises Marattia salicina as a synonym.

d Considered endemic at time of listing; however, it has been recorded in New Zealand. The New Zealand Plant Conservation Network describes its status as “Non-resident Native—Vagrant”, which is defined as “Taxa whose occurrences, though natural, are sporadic and typically transitory, or migrants with fewer than 15 individuals visiting New Zealand per annum.”

e Considered endemic at time of listing, but also now reported from New Zealand (Renner & Beadel 2011).

Except where they are also listed as threatened, recovery plans are not required for species listed as migratory or marine under the EPBC Act. A Wildlife Conservation Plan for Seabirds (Commonwealth of Australia 2022) has been prepared to guide the management actions necessary to support listed marine and migratory seabirds. Section 1.2.6 provides an overview of the region’s seabirds and identifies those which are listed as migratory and/or marine. Section 6.4 also contains profiles for these species (including details of actions to guide their management).

The plan does not fully address some locally significant species such as the white-necked petrel (Pterodroma cervicalis), the providence petrel (P. solandri) and slender-billed white-eye (Zosterops tenuirostris) that are not currently listed under the EPBC Act. However, some information on these species is included, and recovery actions identified in the plan (such as managing predators and restoring native vegetation) are likely to benefit non-listed species irrespective of conservation status.

The plan is intended to work in a complementary way with other existing plans to support the management of common pressures and the conservation of species, their habitats and the wider ecosystems of Norfolk Island. Such plans include the Norfolk Island Marine Park Plan, the Norfolk Island National Park and Norfolk Island Botanic Garden Management Plan, and the Wildlife Conservation Plan for Seabirds, among others. Interactions with other plans are discussed in more detail in Section 5.2.

1.1.2        Legislative and administrative context

Norfolk Island is an external Territory of Australia administered by the Australian Government through the Department of Infrastructure, Transport, Regional Development, Communications and the Arts (DITRDCA). The Australian Government is responsible for the delivery of national and state‑type services to Norfolk Island. Norfolk Island Regional Council is responsible for local government functions on Norfolk Island and may deliver some state-type functions under agreements with DITRDCA.

The EPBC Act has been in force on Norfolk Island since 1999. The Act is the Australian Government’s central piece of environmental legislation. It provides a legal framework to protect and manage nationally and internationally important flora, fauna, ecological communities, and heritage places—defined in the EPBC Act as Matters of National Environmental Significance (MNES). MNES on Norfolk Island include:

• World Heritage properties
• nationally threatened species and ecological communities
• migratory species
• Commonwealth marine areas.

The EPBC Act requires that an action that will have, or is likely to have, a significant impact on MNES must be referred to the Minister for the Environment for a decision on whether assessment and approval is required under the EPBC Act. The EPBC act also requires that an approved Conservation Advice be in place for entities listed as threatened. The Minister for the Environment decides whether a Recovery Plan is also required for threatened species.

Management of threatened species on Norfolk Island requires the input, contribution and coordination of multiple organisations. The relevant organisations and their role and responsibilities in relation to terrestrial threatened species are described in Section 5.1.

The Australian Government’s Threatened Species Action Plan 2022–2032 sets targets and objectives for threatened species recovery and conservation over ten years (DCCEEW 2022b). Under the Action Plan, Norfolk Island has been identified as one of 20 priority places and the Norfolk Island green parrot (Cyanoramphus cookii) as one of 110 priority species.

1.1.3        International obligations

There are 32 bird species that occur in the Norfolk Island Group that are subject to one or more of the bilateral migratory bird agreements with Japan (Japan Australia Migratory Bird Agreement [JAMBA]), China (China Australia Migratory Bird Agreement [CAMBA]) and the Republic of Korea (Republic of Korea Migratory Bird Agreement [ROKMBA]). Of those species, two are listed threatened species (Table 8). This plan provides recovery guidance for those two species, which complements guidance for these species provided in the Wildlife Conservation Plan for Seabirds (Commonwealth of Australia 2022).

1.1.4        Preparation of the Norfolk Island Region Threatened Species Recovery Plan

The development of the Norfolk Island Region Threatened Species Recovery Plan (‘the plan’) has been coordinated by Parks Australia with assistance from many contributors. The Norfolk Island Region Recovery Plan Steering Committee (consisting of representatives from Parks Australia, Norfolk Island Regional Council and DITRDCA) reviewed the previous plan and guided development of the new plan.

This plan builds on the previous recovery plan but with substantial revision and additional material. A review of the previous plan (see Part 3) showed there had been progress in restoring native vegetation, reducing the impacts of introduced flora and fauna, and increasing some populations, with 53% of the listed threatened species recording increases in population size since the commencement of the 2010 recovery plan (see Table 21). Most of these increases can be attributed to recovery actions—for example, efforts to protect the Norfolk Island green parrot and Kermadec petrel (Pterodroma neglecta neglecta) from predation, and extensive propagation and planting of threatened plants.

Some recovery objectives of the previous recovery plan were not met due to limited progress in implementing the identified actions. Delivery was hampered by several factors, including ambitious objectives that required more than one decade to achieve. The review made a series of recommendations, including having measurable targets, comprehensive and robust estimates of costs, a clear and logical framework for monitoring and evaluation, and a clear outline of roles and responsibilities. Those recommendations have been addressed in this new plan which has benefited not only from the review but from new information produced by research on the islands in recent years, analyses conducted specifically to support development of the plan, and insights from experiences in other places in the south-west Pacific.

An expert workshop involving 32 specialists from Norfolk Island, Australia and New Zealand was held in July 2021 to determine targets and priority actions for the threatened species included in this plan. A decision support tool developed by Parks Australia and the National Environmental Research Program Environmental Decisions Hub (Di Fonzo et al. 2017) was used to help guide resource allocation for threatened species management. Many of the workshop participants, along with other experts, subsequently contributed to an assessment of risks to individual species and/or to development of the text of the plan.

Meetings were held with the Norfolk Island Flora & Fauna Society and the community in August 2021 and May 2023 and with the Norfolk Island National Park Advisory Committee in September 2021.

Further workshops were held in 2022 with Parks Australia and Norfolk Island Regional Council staff, focusing on indicators of management effectiveness and on estimating the costs of implementing the plan. More accurate and detailed costs of management programs were determined using a local and regional-scale conservation budgeting framework and tool previously used to develop cost estimates of threatened species recovery across Australia (Yong et al. 2023). That cost analysis was led by Chuanji Yong.

This plan was made available for public comment during 2023. Relevant comments in submissions received were considered and addressed in the final drafting phase.

1.2         The Norfolk Island Group

1.2.1        Regional overview

The Norfolk Island Group is founded on a seamount of volcanic origin in the South Pacific Ocean (29°02’S, 167°57’E), between New Caledonia, Lord Howe Island and New Zealand, at the intersection of tropical and temperate oceanic island environments. The Group consists of the main island of Norfolk Island, the small uninhabited Nepean and Phillip Islands, and numerous rocky islets dotted about the Norfolk Island coastline. The island is predominantly bounded by precipitous cliffs of basalt and tuff. The plateau averages around 100 m above sea level with two peaks in the north over 300 m. Norfolk Island is approximately 1,450 km from Brisbane and 1,100 km from Auckland. The nearest islands to Norfolk Island are New Caledonia (767 km to the north) and Lord Howe Island (896 km to the southwest). The islands of the Norfolk Group are truly oceanic. Few oceanic islands occur in the Pacific Ocean between latitude 25°S and 35°S, and the islands are an important link between tropical and temperate environments.

Norfolk Island has a land area of 3,455 hectares (ha) of which approximately 75% is held privately as freehold or leasehold. The remainder is a combination of Commonwealth Crown land or Council‑owned land, designated for a range of public uses, including conservation. Currently, 650 ha of the Island Group are managed as national park. This includes the Mt Pitt section of Norfolk Island, the Norfolk Island Botanic Garden and all of Phillip Island. An additional 237 ha are protected in a network of 18 public reserves, most of which are located along the coastline.

1.2.2        Geology and geomorphology

Norfolk and Phillip Islands are small remnants of a large volcano that developed on the Norfolk Ridge. The volcanic landmass of which they are a small part was created during several eruptions between 3.1 and 2.3 million years ago (Jones & McDougall 1973). Nepean Island, located between Norfolk and Phillip Islands, is not volcanic in origin and is composed of calcarenite (a form of limestone). It was formed from windblown sand dunes during the last two ice ages (Jones & McDougal 1973; NIP & FS 2003).

One of the two main volcanic vents was in the vicinity of Mt Bates (318 m above sea level) and Mt Pitt (316 m above sea level), which now stand as the two highest peaks on the main island. The other significant geological feature is the southern plateau, formed from horizontal sheets of basalt, which occupies most of the main island and is dissected by deep narrow valleys (Jones & McDougall 1973). There is a smaller plateau in the north-west near Duncombe Bay. The fourth physical region is the coastal lowland around Kingston, comprising the land formed by infilling behind the calcarenite barrier (Abell & Falkland 1991). Precipitous cliffs surround the island and most of the valleys hang over the cliffs, suggesting that wave action has been the most important force in shaping the features of the landscape.

Surface water is restricted on Norfolk Island, with no lakes and few wetlands. The three permanently flowing streams on the southern side of the island are relatively small compared to the valleys they occupy, suggesting that they were largely eroded during a wetter period. These three streams are the only creek lines that drain down to sea level. The northern portion of the island has only sparse and intermittent creek lines.

Groundwater flow systems are localised, following the major drainage basins, with vertical drainage through the weathered volcanics leaking into the underlying agglomerate and basalt aquifers, which are generally hydraulically interconnected (Petheram et al. 2020). Recharge occurs across the elevated portions of the island, including the southern and northern plateaus. A high-level water table with hydraulic potential occurs under the southern plateau at a height of over 100 m above sea level (Petheram et al. 2020).

On Phillip Island there are three (possibly four) volcanic vents. At 280 m, Jacky Jacky is the highest point on Phillip Island with steep cliffs fringing the perimeter. There are no permanent streams on the island. The tuff and ash beds are very friable and sensitive to erosion. There has been severe erosion on Phillip Island as a result of vegetation destruction by introduced goats (Capra aegagrus hircus), pigs (Sus scrofa) and rabbits (Oryctolagus cuniculus); in some places at least two metres of topsoil was lost (Melville 1969; see also section 1.2.7). Some of the valleys on Phillip Island have formed within living memory, and soil washed from the island colours the sea red following rain.

1.2.3        Soils

Clay-rich soils, produced by normal weathering of basalt rock, cover much of Norfolk Island (Abell & Taylor 1981). These soils are nutrient rich, well structured, friable and highly permeable. They do not hold moisture well, so native vegetation is susceptible to stress during long dry periods. The soils are also prone to mass movement such as soil creep, slumps and landslips in areas where vegetation cover has been reduced (Petheram et al. 2020).

CSIRO identified 11 soils on Norfolk Island during surveys in 1954 (Stephens and Hutton 1954). Petheram et al. (2020) also describe the Norfolk Island soils with additional hydrological context—see Map 2 and Table 5 for the soils mapped in these studies and their properties.

A digital soil attributes modelling exercise was undertaken as part of the Norfolk Island Water Resource Assessment (Petheram et al. 2020), mapping attributes relevant to ground and surface water such as permeability, water holding capacity, drainage, clay content, and soil thickness. These data are available from the CSIRO data access portal.

Map 2 Soil map of Norfolk Island

Source: Stephens and Hutton 1954.

Table 5 Soils of Norfolk Island

Sources: Stephens & Hutton 1954; Petheram et al. 2020.

1.2.4        Climate

The sub-tropical climate of Norfolk Island is moderated by the surrounding sea and is primarily affected by a belt of high-pressure systems that oscillate over the island. Annual and diurnal temperature ranges are small. The average daily minimum temperature ranges from 13°C to 15°C in winter and between 18°C and 20°C in summer. Average daily maximum temperatures range from 18°C to 19° C in winter and between 23°C and 25°C in summer. Annual average rainfall is 1,312 millimetres, peaking from May to August. Prevailing winds are primarily east to south-easterly during summer and autumn, swinging to the south or south-west in mid-winter, and returning to south in spring. Tropical cyclones occasionally have an influence in the early part of the year (Bureau of Meteorology 2021).

1.2.5        Human history

Excavations on Norfolk Island have revealed evidence of a small Polynesian village (Anderson 1996) which pre-dates European settlement. Two Polynesian adzes (stone axes) and stone flakes were discovered during a dig on Norfolk Island in 2022, which provide strong evidence for a Polynesian settlement on the island during the 13th and 15th centuries CE (Anderson & White 2001; Australian Museum 2022). The presence of Polynesians on Norfolk Island prior to European settlement is further supported by the presence of a banana grove, Polynesian rats (Rattus exulans) and stone axes found elsewhere on the island (Norfolk Island Conservation Society 1988; Gilmour & Helman 1989a, 1989b).

The island was first settled by Europeans in 1788, at which time it was uninhabited. The aim of the initial European settlement of the island was to clear land for the cultivation of native flax, as well as grains and vegetables to support the new colony at Port Jackson. The island had two periods of operation as a penal colony: firstly from 1788 until 1814, after which it remained uninhabited for 10 years, and again from 1825 until 1855.

At the time of settlement, Norfolk Island was covered with dense forest, which now largely remains only on the highest land (Green 1994), while Phillip Island was mostly covered with white oak (Lagunaria patersonia)/low forest (Mills 2009b). Since settlement, land use has had a very significant impact on vegetation. Accounts by early settlers describe the vegetation on Norfolk Island as very dense with complete canopy excluding light, very little growth on the forest floor and abundant towering emergent pines (Hoare 1969). The early penal colonies and free settlers progressively cleared much of the natural vegetation for agriculture and timber export during the first 75 years of settlement. They also stocked Phillip Island with pigs, goats and rabbits to provide a food source, and these animals were left behind when the settlements folded.

During its time as a penal colony, most of the island, apart from the two mountains and the land to the north, was cleared for crops or pasture (Benson 1980). Following the removal of convicts in 1855, the island supported a smaller agricultural community. Only about 100 ha were under cultivation, and much of the island was neglected and invaded by weeds (Gilmour & Helman 1989a, 1989b). In 1856, the inhabitants of Pitcairn Island were relocated to Norfolk Island. These settlers cultivated the land that had been cleared by the penal colony, and agriculture became the economic base of the island. Trade with Australia in several crops developed, with farmers transitioning from one crop to another as markets changed. Whaling was also an important commercial activity, carried out periodically for over a century from about 1850.

By the mid-1920s, previously cleared land again supported Norfolk Island pines, but dense stands occurred only in areas too steep to support grazing (Benson 1980). Introduced weeds invaded the remnant rainforest to the north of the mountains, and very little of the original vegetation was left in its virgin state (Benson 1980). Following wartime construction of the airfield, the economy of the island changed, and tourism became the dominant industry on Norfolk Island.

1.2.6        Native species

Norfolk Island has 58 threatened species listed under the EPBC Act comprising 46 plants, five birds, two reptiles and five endemic land snails (two of which are likely extinct). An additional six bird species are known to have become extinct in historical times, along with two endemic plant species. Alongside the threatened species are many other terrestrial species including birds, invertebrates and plants.

Fauna

Norfolk Island has 12 fauna species that are listed under the EPBC Act as threatened, comprising four land birds, one seabird, two reptiles and five endemic land snails (Table 4). Six species of land birds, endemic to the island, are listed as extinct under the EPBC Act, while another species that has become extinct since European settlement, the Norfolk Island ground dove (Gallicolumba norfolciensis), is not listed under the Act. There are a further 22 species of birds occurring on Norfolk Island that are listed as migratory or marine under the EPBC Act (Table 8). There are 32 species relevant to Norfolk Island National Park and Botanic Garden that relate to one or more of the bilateral migratory bird agreements with Japan (JAMBA), China (CAMBA) and the Republic of Korea (ROKAMBA). Of those species, two are listed threatened species and discussed in this plan.

Invertebrate fauna

Norfolk Island’s invertebrate fauna — like that of many islands around the world — is relatively depauperate, with many groups having few or no species present. However, it is richer than would be expected given the island group’s small size and isolation. The invertebrate fauna of Norfolk Island remains poorly understood.

Previous invertebrate work has primarily been in the form of taxonomic publications or biosecurity surveys. The Norfolk Island Quarantine Survey 2012–2014 focused on agricultural plant pests and parasites of domestic animals, significantly improving the understanding of these groups (Maynard et al. 2018). The report documented more than 1,190 species of invertebrates, many of which had not been recorded from the island previously.

Comparatively little is known about native invertebrate fauna on Norfolk Island, and it is likely many invertebrates remain undescribed. There is currently a significant volume of work underway to improve knowledge of the island’s native invertebrates, particularly the snails and insects, as well as additional work on agricultural and horticultural pests. The following section provides details on groups of invertebrates for which significant survey work has been conducted.

Land snails

A major component of the biota of Pacific islands is land snails, which are recognised for their high levels of diversity and endemism (Cowie 2001). Many of these snails are now threatened with extinction (Ponder 1997). The Norfolk Island Group once supported many species of land snails, some of which are only known from fossil deposits and many of which were endemic. The non‑marine molluscan fauna for Norfolk Island consists of 68 terrestrial species and one freshwater species and is almost entirely endemic (Smith 1992; Ponder 1997).

Currently, there are differences between the listing of Norfolk Island mollusc species under the EPBC Act and on the IUCN Red List. Five species are listed as Critically Endangered under the EPBC Act (Table 6): Campbell’s keeled glass-snail (Advena campbellii), Gray’s glass-snail (A. grayi), Phillip Island glass-snail (A. phillipii), Suter’s striped glass-snail (A. suteri) and Stoddart’s glass-snail (A. stoddartii). In comparison, twenty species appear on the IUCN Red List: six species are listed as extinct, including the only recorded freshwater mollusc (Posticobia norfolkensis), four species are considered Endangered, eight species are considered Vulnerable, and two species are data deficient. The same threats that have resulted in the extinction of several birds and plants—environmental degradation and the introduction of feral animals—have probably affected the terrestrial snail fauna as well (Ponder 1997). Surveys in 2020 resulted in the rediscovery of one species, Allenoconcha quintalia (previously known as Nancibella quintalia), which was last collected in 1889 and was listed as Extinct by the IUCN (Hyman & Köhler 2020). There is a need to reassess the listings of other endemic snail species and evaluate whether additional species should be listed under the EPBC Act.

Of the five EPBC listed threatened molluscs, only three are known to persist. Campbell’s keeled glass‑snail occurs within the Mt Pitt section of the Norfolk Island National Park, Gray’s glass‑snail occurs on Phillip Island, and Suter’s striped glass-snail is currently only found within Hundred Acres Reserve (Map 3). More detailed individual species information is included in Part 6.

Taxonomy of the species previously classified in the genera Advena, Mathewsoconcha and Quintalia was revised in 2023, bringing all five Critically Endangered species into the single genus, Advena (Hyman et al. 2023).

Table 6 EPBC listed threatened molluscs of the Norfolk Island Group

a Hyman et al. (2023) have completed a revised taxonomy of the Norfolk Island microcystid snails and concluded that the three genera, Advena, Mathewsoconcha and Quintalia, should be combined into the single genus Advena. As these species have been listed under the EPBC Act under previous names, the listed name appears first, with the revised names in brackets.

Orthoptera (grasshoppers, crickets and katydids)

A total of 20 orthopterans are known from the Norfolk Island Group, 11 of which are endemic. The cricket Nesitathra philipensis is believed to be endemic to Phillip Island where it lives among seabird colonies. Many of Norfolk Island’s orthopterans share close affinities with those of Lord Howe Island, with many species on both islands classified within the same genera. The crickets and katydids are among the largest and most abundant indigenous herbivores and several species can be commonly found feeding on the foliage of forest trees and shrubs at night. The chorus formed by the calls of many of the cricket and katydid species, particularly at dusk, is a distinct feature of Norfolk Island’s forest ecosystems (Rentz 1988).

Lepidoptera (moths and butterflies)

At least 263 species of lepidopterans from 29 families have been recorded on Norfolk and Phillip Islands. Of these, more than 40 are believed to be endemic, including Nesiotica cladara (which belongs to an endemic genus) and two endemic subspecies of butterfly both derived from New Caledonia (Holloway 1977). Numerous pest species are known to be present that have either been introduced or established naturally (Edwards 1985; Maynard et al. 2018).

Coleoptera (beetles)

The coleopteran fauna of Norfolk and Phillip Islands is depauperate, typical of oceanic islands. At least 304 species in 46 families have been identified, of which at least 65 species are considered endemic (Weir 1985). There have been 57 species found on Phillip Island including five endemic species (Weir 1985).

The ground beetles (Carabidae) are the most well-studied of all beetle families present on the island, though most endemic species remain poorly known. A total of 16 species are known from the island, seven of which are known to be endemic (Moore 1985; Giachino 2005).

The endemic stag beetle (Lamprima aenea) is listed as Vulnerable on the IUCN Redlist and is currently Norfolk Island’s only endemic insect species to have a threat status (IUCN 2022).

Hymenoptera (bees, wasps and ants)

The Norfolk Island Group contains a depauperate hymenopteran fauna. There are 219 species recorded from Norfolk Island or Phillip Island including nine endemic species (Naumann 1984, Smithers 1998). Many of the Hymenoptera are associated with low flowering herbs and annuals that are abundant in some parts of Phillip Island but excluded by introduced grasses on Norfolk Island (Naumann 1984).

Fifteen species of ants are known from Norfolk Island including the endemic species, Oligomyrmex norfolkensis, Tetramorium antipodum and Iridomyrmex phillipensis, the latter of which is currently only known from Phillip Island (Taylor & Brown 1985, Smithers 1998, Heterick & Shattuck, 2011). Several of the ant species are cosmopolitan or introduced and most of the others can be attributed to the Australian element of the Norfolk fauna, although some are found on Lord Howe Island or in New Zealand (Holloway 1977). The invasive Argentine ant (Linepithema humile) was first reported on Norfolk Island in 2005 (Davis 2008).

Other insects

Most groups of insects on Norfolk Island are poorly known, with substantial further work required to understand the full diversity. An order of insects that has received substantial recent attention is the thrips (order: Thysanoptera). When a catalogue of the island’s insects was compiled in 1998 (Smithers 1998), only three species of thrips were recorded from the island, two of which were endemic. Following extensive survey work from 2012–2014, Mound and Wells (2015) increased this total to 66 species, at least 12 of which are endemic. Significant work has also been undertaken on bark lice (order: Psocodea), with at least 11 known endemic species (Smithers et al. 1999).

The true flies (order: Diptera) have received relatively little attention, with future surveys likely to document many species as-yet unrecorded from the island, likely including numerous undescribed endemic species.

Myriapoda (centipedes and millipedes)

The endemic centipede, Cormocephalus coynei, was recorded on Phillip Island in 1792 but was not formally described until much later (Halpin et al. 2021a). It is restricted to Phillip and Nepean Islands, found in litter, soil and under bark (Koch 1984), and can grow to almost one foot (30.5cm; Halpin et al. 2021a). The species has a highly varied diet including crickets, seabird chicks, geckos and skinks, and even fish dropped by black noddies (Anous minuta; Halpin et al. 2021a).

Beyond the charismatic C. coynei, relatively little is known of Norfolk’s myriapod fauna. Only a handful of species have ever been documented from the island (Johns 1967).

Freshwater invertebrates

The small freshwater crab, Amarinus lacustris, is known to occur on Norfolk Island but it is not common or widespread (McCormack & Coughran 2009). Specimens of this elusive species have been collected at two locations on Norfolk Island—Bumboras Creek and Kingston. Anecdotal information suggests that land crabs (Geograpsus greyii) were well known in the past on Norfolk Island, but they were not detected in 2009 (McCormack & Coughran 2009). Local advice suggests the land crabs are in the order of 60–70mm carapace width with a hairy, purple appearance and that they live within 1km of the ocean under logs in the forests. In 2019, a sighting of this land crab was recorded on Philip Island.

The same 2009 study found one endemic species of shrimp (Paratya norfolkensis), and a population of freshwater amphipods. Paratya norfolkensis is listed as Critically Endangered on the IUCN Red List. Two species of freshwater snails were found to be plentiful in the streams. Although not identified to species level, it appears that representatives of both the families Planorbidae and Lymnaeidae were collected.

Reptiles

Two native land reptiles occur in the Norfolk Island Group: the Lord Howe Island gecko (Christinus guentheri) and the Lord Howe Island skink (Oligosoma lichenigerum), which are both listed as Vulnerable under the EPBC Act (Table 7). These species are restricted to the Norfolk and Lord Howe Island groups. Neither is now found on Norfolk Island, but both species occur on Phillip Island. The gecko also occurs on Nepean Island and the small rocky islets (Map 4)—Moo-oo Stone, Bird Rock and Green Pool Stone (Cogger 2004). See the individual species entries for the threatened reptiles in Part 6 for more detailed information.

The introduced Asian house gecko (Hemidactylus frenatus) has been recorded at three sites on Norfolk Island, primarily in the Burnt Pine township (in buildings). This species has been implicated in the decline of native gecko species in other parts of its introduced range (Hoskin 2011).

Table 7 EPBC listed threatened reptiles of the Norfolk Island Group

Birds

The fauna of the Norfolk Island Group is notable for its endemic land birds and large numbers of seabirds, which are the most visible and most well studied terrestrial fauna element. More than 150 species of birds have been recorded on Norfolk Island and adjacent islands (Hermes et al. 1986; Christian 2005; M Christian 2024, pers comm 12 January). Of these, 32 species are resident breeding land or freshwater birds, 13 are current regular breeding seabirds, and the remainder are non‑breeding migrants or vagrants (Schodde et al. 1983; Christian 2005; N Carlile 2024, pers comm 12 January). Many of the breeding land and freshwater birds were deliberately introduced or arrived on the island independently following European settlement.

Land birds

Of the 14 species and subspecies of land birds endemic to Norfolk Island, only seven are extant (Table 8). Seven are presumed extinct, though only six are listed as Extinct under the EPBC Act (the Norfolk Island ground dove is known to be extinct but is listed as migratory). Four of the seven extant species are listed under the EPBC Act.

The decline of the land birds occurred during two distinct periods. During the first period (between settlement and approximately 1900), the Norfolk Island subspecies of the New Zealand pigeon (Hemiphaga novaeseelandiae spadicea), the Norfolk Island ground dove (Gallicolumba norfolciensis), the Norfolk Island kaka (Nestor productus), and the Norfolk Island subspecies of the Tasman starling (Aplonis fusca fusca) became extinct (Schodde et al. 1983).

In the second period of decline (post-1940s), the long-tailed triller (Lalage leucopyga leucopyga) and the grey-headed blackbird or island thrush (Turdus poliocephalus poliocephalus) disappeared (Schodde et al. 1983; Dutson 2013). There were serious declines in the populations of the Norfolk Island morepork (Ninox novaeseelandiae undulata) (Olsen 1996; Olsen et al. 1989) and the Norfolk Island green parrot (Cyanoramphus cookii) (Hicks & Greenwood 1989; Hill 2002; Ortiz-Catedral et al. 2018). Populations of more common land birds such as the Norfolk Island robin (Petroica multicolor) and the slender-billed white-eye (Zosterops tenuirostris) also declined over this period.

The post-1940s period of species decline coincided with many changes to the Norfolk Island environment. These were: the introduction of the black rat (Rattus rattus) in the mid-1940s; modification to the environment through clearing, grazing and forestry activities (Smithers & Disney 1969); the replacement of native vegetation by introduced weed species such as guava, olive and lantana (Smithers & Disney 1969); the introduction or self-introduction of several non-native birds (Schodde et al. 1983); a rapid increase in the tourist population; and increasing use of agricultural poisons such as organochlorides and dieldrin (Olsen 1996). The most recent extinction of a land bird from Norfolk Island was the white-breasted white-eye (Zosterops albogularis), which was last seen in 2004.

Currently, the Mt Pitt section of Norfolk Island National Park is the stronghold for the Norfolk Island green parrot, but there is growing anecdotal evidence that its range has increased substantially, and the species is now regularly seen in areas well outside of the national park boundary (Map 5).

The Norfolk Island morepork is distributed across the national park with a higher density on the southern slopes of Mt Pitt and Mt Bates, and more sparsely distributed across the rest of Norfolk Island (Map 6).

The Norfolk Island golden whistler and the Norfolk Island robin are both endemic threatened forest birds whose ranges include the Mt Pitt section of the Norfolk Island National Park plus some adjacent and nearby forested areas (Map 7 and Map 8). The Norfolk Island golden whistler is more widespread across these areas than the Norfolk Island robin despite having specialised habitat requitements. See the individual species entries in Part 6 for more detailed information on each of the above-mentioned threatened bird species.

Seabirds

Of the 14 breeding seabirds, all are listed as marine species, four are listed as migratory species and one (the Kermadec petrel) is listed as Vulnerable under the EPBC Act (Table 8). There are two additional seabirds that may breed on the Norfolk Island Group, but this is unconfirmed: the Australasian gannet (Morus serrator; listed as Marine) and the Tasman white-bellied storm-petrel (Fregetta grallaria grallaria; listed as Marine and Vulnerable).

At the time of the first European settlement, Norfolk Island supported large populations of breeding seabirds, dominated by the wedge-tailed shearwater (Ardenna pacifica) nesting in the summer and the providence petrel (Pterodroma solandri) nesting in the winter. Food and supplies for the settlement were in short supply and thousands of birds from the large colony of providence petrels nesting around the peaks of Mt Pitt and Mt Bates were eaten, contributing (along with the activities of introduced feral pigs) to the elimination of the breeding colony. The species now breeds largely on Lord Howe Island and Phillip Island.

Today, ground nesting seabirds in the Norfolk Island Group are largely restricted to Phillip Island, Nepean Island and rock stacks surrounding Norfolk Island. This is due to predation by rats and feral and free-roaming cats (Felis catus), degradation of breeding sites through clearing and introduction of weeds, and disturbance by humans and domestic animals. The absence of mammalian predators and permanent inhabitants on these islands are critical for the survival of these colonies.

The Kermadec petrel breeds on islands across the Pacific Ocean as far east as Easter Island. In the Norfolk Island Group, a small population breeds on Phillip Island. See Map 5 and the Kermadec petrel species profile in Part 6 for more detailed information.

Table 8 Endemic and/or EPBC listed avian fauna of the Norfolk Island Group

EPBC listed threatened species that are still extant are in bold. Extinct species are noted as such in the EPBC Act status column. Range refers to the area of occurrence and not the breeding range of the species.

a Scientific names used are those that are currently accepted by the Australian Plant Census (APC) for flora and the Australian Faunal Directory (AFD) for fauna. Where species have been listed under the EPBC Act under previous names, the listed name appears first in tables, with the APC/AFD name in brackets.

b Excludes non-breeding visitors and vagrants.

c Known to be extinct but is only listed as Migratory, not extinct under the EPBC Act. The species name is not recognised by the AFD.

Mammals

The only native land mammals that have been recorded on Norfolk Island are the Eastern free-tail bat (Mormopterus norfolkensis) and Gould's wattled bat (Chalinolobus gouldii), although it is likely that the former was described from Norfolk Island in error and never occurred there (Hoye et al. 2008). Anecdotal sightings of the latter were reported around the time the last recovery plan was prepared (Director of National Parks 2010) and more recently, but scientific surveys are required to confirm the species’ potential presence.

As in many other island ecosystems, introduced mammals have been responsible for significant environmental degradation. The Polynesian rat was introduced by early Polynesian visitors prior to European arrival. The black rat was possibly introduced from a shipwreck in 1942, but it could have been introduced any time since European settlement. There is a strong likelihood that the house mouse (Mus musculus) and the feral cat were introduced during early settlement on the island (Wilson 2002).

Fish

In most creek systems, McCormack & Coughran (2009) found one species of eel (Anguilla sp.) and large numbers of small exotic pest fish species, mostly Gambusia holbrooki (Gambusia, mosquito fish) and Poecilia reticulata (guppies).

Distribution of threatened fauna

Map 3–9 present the known distribution of threatened fauna on the Norfolk Island Group. Table 9 summarises the distribution of threatened fauna by proportion across tenure types, dividing land into the Norfolk Island National Park, public reserves, and other land.

Map 3 Known locations of threatened molluscs on the Norfolk Island Group

Campbell’s keeled glass-snail (Advena campbellii) occurs in the Mt Pitt section of the national park, Suter’s striped glass‑snail (A. suteri) occurs in Hundred Acres Reserve, and Gray’s glass-snail (A. greyi) occurs on Phillip Island.

Source: Hyman & Kohler 2020; Tweed 2023.

Map 4 Distribution of threatened reptiles on the Norfolk Island Group

The Lord Howe Island skink (Oligosoma lichenigerum) occurs only on Phillip Island. The Lord Howe Island gecko (Christinus guentheri) has been found on Nepean and Phillip Islands and on three small rocky islets—Moo-oo Stone, Bird Rock and Green Pool Stone.

Source: Cogger et al. 2006.

Map 5 Primary distribution of the Norfolk Island green parrot

The stronghold for the Norfolk Island green parrot is within the shaded area. However, its range extends across Norfolk Island.

Source: Macgregor et al. 2021.

Map 6 Range movements of the Norfolk Island morepork on Norfolk Island

Source: Sperring et al. 2021a.

Map 7 Distribution of the Norfolk Island golden whistler

Source: Nance et al. 2021b.

Map 8 Distribution of the Norfolk Island robin

Source: Nance et al. 2021c.

Map 9 Distribution of the Kermadec petrel in the Norfolk Island Group

Source: Carlile and O’Dwyer 2023.

Table 9 Distribution of EPBC listed threatened fauna (excluding species presumed to be extinct) on the Norfolk Island Group across tenure types

Flora

There are 182 recognised native vascular plant species in the Norfolk Island Group (of which about 25% are endemic) and at least a further 430 naturalised species (Mills 2009a; Maynard et al. 2018). Two monotypic endemic genera occur: the rainforest tree Ungeria floribunda, which is listed as Vulnerable, and Streblorrhiza speciosa (Phillip Island glory pea) a presumed extinct but previously endemic vine on Phillip Island (Green 1994).

Forty-six plant species on Norfolk Island are listed as threatened species under the EPBC Act (Table 10). Of these, 30 species are endemic to Norfolk Island and Phillip Island, and two are endemic to Phillip Island only. An additional two species are endemic to the Norfolk Island and Lord Howe Island Groups, and another is found in north-east Queensland as well as on Norfolk Island. The remaining twelve species have their only Australian distribution on the Norfolk Island Group, but also occur in New Zealand or other Pacific islands. There are also 13 plant species that are endemic to Norfolk Island and Phillip Island that are not listed under the EPBC Act (Table 10). See Map 10 for an illustration of the number of threatened plant species occurring within each park and reserve in the Norfolk Island Group. For distribution of individual plant species see the species profiles in Part 6.

Norfolk Island has a relatively diverse and prolific lichen assemblage (Elix et al. 1992) with 190 taxa recorded (ABRS 2017). The areas of subtropical rainforest within the Norfolk Island National Park are the major habitat for lichens, and the higher, moister ridges support the greatest diversity of bryophytes on the island. Invasion of forested areas by woody weeds, particularly red guava (Psidium cattleyanum cattleyanum) and African olive (Olea europaea cuspidata), represents the major threat to lichen species; these two woody species and lantana (Lantana camara) are also a threat to the bryophytes (Elix & Streimann 1985).

Table 10 Threatened and/or endemic plants of the Norfolk Island Group

a Considered endemic at time of listing; however, it has been recorded in New Zealand. The New Zealand Plant Conservation Network describes its status as “Non-resident Native—Vagrant”, which is defined as “Taxa whose occurrences, though natural, are sporadic and typically transitory, or migrants with fewer than 15 individuals visiting New Zealand per annum.”

b Considered endemic at time of listing, but also now reported from New Zealand (Renner & Beadel 2011).

Distribution of threatened flora

Map 10 presents spatial data for known populations of threatened flora on the Norfolk Island Group, showing number of species occurring in the park and reserves.

Table 11 summarises the distribution of each threatened flora species by proportion across tenure types, dividing land into the Norfolk Island National Park, public reserves, and other land.

Map 10 Number of threatened plant species in each park and reserve in the Norfolk Island Group

Spatial data for threatened species locations outside of reserves is not available. For distribution of individual plant species, see Table 11 and Part 6.

Table 11 Distribution of EPBC listed plant species of the Norfolk Island Group across tenure types

Note: Proportion of the estimated population in each area is given for known populations in the national park and public reserves. Suitable habitat may exist in remnant plant communities outside of the parks and reserves for some species (as noted), but data on species occurrence and/or numbers in these areas is limited.

a All species noted as “common recent plantings” are ones that have been sold in significant numbers (hundreds of individual plants) by the Norfolk Island National Park Nursery for planting on private lands and gardens. Such plantings are unlikely to contribute to a species’ breeding population for some years.

bListed under the EPBC Act as Lastreopsis calantha. The Australian Plant Census (APC) accepts Lastreopsis calantha and recognises Parapolystichum calanthum as a synonym.

c Listed under the EPBC Act as Marattia salicina. The APC accepts the name Ptisana salicina and recognises Marattia salicina as a synonym.

d Considered endemic at time of listing, but also now reported from New Zealand (Renner & Beadel 2011).).

1.2.7        Plant communities

The distribution of plant species and communities on Norfolk Island is influenced by altitude, aspect, topography and proximity to the sea. Resulting patterns of precipitation (rainfall, fog and mist) influence plant distributions, and there is a significant difference between the mountains and the southern part of the island, which is drier.

A detailed study of the distribution of the natural vegetation on Norfolk Island—both as it is currently known and as it is best understood to have existed in 1750 (Figure 2) —identified 14 plant communities, each of which supports assemblages of threatened plant species (Table 12): eight forest communities and six non-tree communities (Invasive Species Council & TierraMar 2021). This work built upon previous investigations of the vegetation (Gilmour & Helman 1989a, 1989b; Mills 2007a). In 1750 the vegetation on the island was primarily dense subtropical rainforest, with the endemic Norfolk Island pine (Araucaria heterophylla) particularly abundant on the lower elevations and along the coast. The extent of all native plant communities has been substantially reduced since European settlement (Map 11 and Map 12).

The largest remnant of native forest today occurs in the Mt Pitt section of the national park, spreading down the slopes of the mountain and into the valleys between Mt Pitt and Mt Bates. There are also smaller remnant forest patches in lower areas on the island. Moist palm valley forest and moist upland hardwood forest occur largely in the national park, while most of the coastal non-tree communities occur in public reserves and on private land. Many parts of the island are now covered by non-remnant vegetation including large patches of woody weeds, pastures and exotic gardens. Some of this non-remnant vegetation may be significantly disturbed but still contain native plant assemblages. Such patches may have high conservation potential if restored.

At the time of European settlement, Phillip Island probably supported six plant communities including moo-oo (Cyperus lucidus) sedgeland, shrub thickets on exposed areas and forest in the valleys, with emergent pines throughout (Cogger 2004; Mills 2009b); however, there is no record of the exact communities that originally existed (see Table 13). Phillip Island was severely eroded by grazing by goats, pigs and rabbits, which were introduced by the early British colonists. These introduced mammals almost completely removed the native vegetation, which was followed by the loss of virtually all topsoil on the island. Pigs and goats were eradicated in the early 1900s, while the last rabbit was eradicated in 1986 (Mills 2009b). There has since been a significant regeneration of vegetation on the island, particularly in the gullies where accumulated eroded soil and runoff have provided suitable conditions for plant growth (Cogger 2004; Mills 2009b). Some native plant communities are developing well, such as the moo-oo sedgeland, although the forest community of the valleys is likely to take the longest to reach stability (Mills 2009b). Research in 2008 found that the vegetation on Phillip Island was a mixture of 42 native species and 60 exotic weed species (Mills 2009b).

Figure 2 Photos of the native plant communities on Norfolk Island

Table 12 Description of the native plant communities found on Norfolk Island and the threatened plant species that may occur within them

The native plant communities listed in Table 12 are all remnant communities in which the main native canopy is intact. Non-remnant vegetation may have been significantly disturbed (for example, by weed invasion and clearing), but may still resemble one of the native plant communities and potentially be suitable for restoration. Non-remnant vegetation also includes plantations of native species such as pine plantations.

Source: Invasive Species Council & TierraMar 2021.

Table 13 Plant communities of Phillip Island

The first six plant communities described have been postulated by Mills (2009b) for pre-European Phillip Island. Remnants and/or regrowth of these communities can be found on Phillip Island today.

Source: Mills 2009b.

Distribution of plant communities

The distribution of plant communities existing in 1750 and present in 2020 are shown in Map 11 and Map 12. Table 14 summarises the area of native plant communities (remnant and non-remnant) on Norfolk Island predicted for 1750 and estimated for 2020. Table 15 summarises the current distribution of remnant plant communities by proportion across tenure types, dividing land into the Norfolk Island National Park, public reserves, and other land.

Map 11 Norfolk Island native plant communities present in 1750

Source: Christian & Mills 2021.

Map 12 Norfolk Island native plant communities present in 2020

Source: Christian & Mills 2021.

Table 14 Area of native plant communities (remnant and non-remnant) on Norfolk Island predicted for 1750 and estimated for 2020, and percentage remaining in 2020

Source: Christian & Mills 2021.

a Non-remnant vegetation may have been significantly disturbed (for example by weed invasion and clearing) but may still resemble one of the native plant communities and potentially be suitable for restoration.

Table 15 Distribution of remnant plant communities present in 2020 on Norfolk Island across tenure types

1.2.8        Habitat critical to survival of threatened species

The EPBC Act specifies that a recovery plan must describe to the extent practicable, and with spatial information, areas of habitat that are critical to the survival of the species or ecological communities, and what must be done to stop the decline and support the survival of a threatened species or community, including actions to protect and restore habitat. Habitat is a species-specific concept; it refers to the resources and conditions present in an area and not to a specific vegetation type or land cover (Hall et al. 1997; Kirk et al. 2018). Habitat is the sum of the specific resources needed for a species to occupy an area, and to survive and reproduce there (Hall et al. 1997; Kirk et al. 2018).

All the native plant communities on Norfolk Island provide habitat for threatened plant species (Table 12). The remaining areas of moist palm valley forest, moist upland hardwood forest, pine‑hardwood ridge forest, viny hardwood forest and sheltered coastal forest in and around the Mt Pitt section of the national park support the core parts of the populations of the Norfolk Island green parrot, Norfolk Island golden whistler, Norfolk Island robin and Campbell’s keeled glass-snail, as well as the greatest density of Norfolk Island morepork territories (TSSC 2016a; TSSC 2016b). Pine/oak vegetation supports the remaining population of Suter’s striped glass-snail. Gray’s glass-snail has been found in flax on slopes on Phillip Island. Some species also occur in areas of non-native vegetation. For example, the Norfolk Island morepork, green parrot and robin are found in both native and weed-infested forests (Garnet & Crowley 2000; TSSC 2016a; TSSC 2016b). For more information on habitat requirements of individual species, see Part 6.

The extent of native vegetation on the islands has been greatly reduced since European settlement (Map 11 and Map 12; Table 13 and Table 14). The remaining fragments of natural or near-natural native vegetation are largely contained within the network of Australian Government and Norfolk Island Regional Council protected areas, together with small parcels of privately owned land (Table 16 and Map 12). All vegetation in these areas represents habitat critical for the survival of the taxa in areas covered by this plan.

In view of the restricted ranges of all listed species to which the plan applies (both in absolute terms and relative to their original ranges), all sites known to currently support any threatened species, or containing remnant native vegetation, should be viewed as critical for the group of threatened species collectively. However, these areas alone may not be sufficient. Areas of the island that have vegetation retaining some native elements, or which otherwise provide opportunities for restoration of vegetation, are likely to be important in supporting recovery (refer to the species profiles in Part 6 for more detailed information about the range and habitat requirements of individual species).

Table 16 Sites of significant native vegetation in the Norfolk Island Group, including in the national park, public reserves and other locations