Approved Recovery Plan
Lord Howe Placostylus Placostylus bivaricosus (Gaskoin, 1855) Recovery Plan
October 2001 © NSW National Parks and Wildlife Service, 2001. This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced without prior written permission from NPWS.
NSW National Parks and Wildlife Service 43 Bridge Street (PO Box 1967) Hurstville NSW 2220 Tel: 02 9585 6444 www.npws.nsw.gov.au
For further information contact Threatened Species Unit Conservation Programs and Planning Division, Northern Directorate NSW National Parks and Wildlife Service Locked Bag 914 Coffs Harbour NSW 2450 Tel 02 6651 5946
Cover illustration: Lord Howe Placostylus Placostylus bivaricosus Illustrator: Ann Sheppard
This plan should be cited as follows: NSW National Parks and Wildlife Service (2001). Lord Howe Placostylus Placostylus bivaricosus recovery plan. NPWS, Hurstville, NSW.
ISBN 0 7313 6129 6 National Parks and Wildlife Service Recovery Planning Program
Lord Howe Placostylus Placostylus bivaricosus Recovery Plan
Foreword
The conservation of threatened species, populations and ecological communities is crucial for the maintenance of this State’s unique biodiversity. In NSW, the Threatened Species Conservation Act 1995 (TSC Act) provides the framework to conserve and recover threatened species, populations and ecological communities through the preparation and implementation of recovery plans.
The preparation and implementation of recovery plans is identified by both the National Strategy for the Conservation of Australia’s Biological Diversity and the draft NSW Biodiversity Strategy as a key strategy for the conservation of threatened flora and fauna. The object of a recovery plan is to document the research and management actions required to promote the recovery of a threatened species, population or ecological community and to ensure its ongoing viability in nature.
The TSC Act requires that the Director-General of National Parks and Wildlife prepare recovery plans for all species, populations and ecological communities listed as endangered or vulnerable on the TSC Act schedules. The TSC Act includes specific requirements for both the matters to be addressed by recovery plans and the process for preparing recovery plans. This plan satisfies these provisions.
This plan describes our current understanding of the threatened Lord Howe Placostylus Placostylus bivaricosus, documents the research and management actions undertaken to date, and identifies the actions required and parties responsible to maximise the opportunity for the species’ ongoing viability in the wild.
Michael Wright Bob Debus MP A/Director-General Minister for the Environment National Parks and Wildlife Service Recovery Planning Program
Table of Contents
1.0 INTRODUCTION...... 1
2.0 DESCRIPTION AND DISTRIBUTION...... 1
3.0 CURRENT CONSERVATION STATUS ...... 1
4.0 HABITAT AND ECOLOGY...... 1
5.0 RELEVANT LEGISLATION...... 2
6.0 RECOVERY PLAN IMPLEMENTATION...... 2
6.1 CRITICAL HABITAT ...... 2 6.2 ENVIRONMENTAL ASSESSMENT ...... 2 7.0 MANAGEMENT ISSUES ...... 3
7.1 THREATS AND REASONS FOR DECLINE ...... 3 7.2 SOCIAL AND ECONOMIC CONSEQUENCES...... 4 7.3 BIODIVERSITY BENEFITS...... 4 8.0 PREVIOUS ACTIONS UNDERTAKEN...... 4
8.1 LISTING UNDER TSC ACT ...... 4 8.2 SURVEY AND RESEARCH ...... 4 8.3 RAT CONTROL...... 4 8.4 PIG AND GOAT CONTROL...... 5 8.5 HABITAT PROTECTION...... 5 8.6 COMMUNITY AWARENESS...... 5 9.0 SPECIES’ ABILITY TO RECOVER ...... 5
10.0 RECOVERY OBJECTIVES ...... 5
11.0 RECOVERY PERFORMANCE CRITERIA...... 5
12.0 RECOVERY ACTIONS...... 6
12.1 SURVEY AND RESEARCH...... 6 12.2 PROTECTION OF EXTANT POPULATIONS AND HABITAT ...... 6 12.3 COMMONWEALTH LISTING...... 6 12.4 COMMUNITY AWARENESS AND INVOLVEMENT ...... 7 12.5 EX SITU CONSERVATION MEASURES...... 7 12.6 RECOVERY TEAM...... 7 13.0 IMPLEMENTATION ...... 7
14.0 PREPARATION DETAILS...... 8
15.0 REVIEW DATE...... 8
16.0 REFERENCES ...... 8
17.0 ACRONYMS USED IN THIS DOCUMENT...... 9
18.0 IMPLEMENTATION TABLES ...... 10
APPENDIX 1 PRIORITY RAT BAITING AREAS FOR THE LORD HOWE PLACOSTYLUS ...... 15
APPENDIX 2 ENVIRONMENTAL IMPACT ASSESSMENT GUIDELINES...... 16
APPENDIX 3 GUIDELINES FOR COLLECTION ...... 19 National Parks and Wildlife Service Recovery Planning Program
TABLES
TABLE 1: RESPONSIBILITY FOR IMPLEMENTATION, TIMING AND PRIORITY OF RECOVERY ACTIONS. PRIORITY IS CATEGORISED AS 1 (ESSENTIAL), 2 (HIGHLY DESIRABLE) OR 3 (DESIRABLE)...... 10 TABLE 2: ESTIMATED COSTS OF IMPLEMENTING RECOVERY ACTIONS. COSTED ACTIONS ARE SUBJECT TO FUNDING AVAILABILITY UNLESS OTHERWISE NOTED. ESTIMATES DO NOT INCLUDE GOODS AND SERVICES TAX...... 11
FIGURES
FIGURE 1. RECORDS OF THE LORD HOWE PLACOSTYLUS ON LORD HOWE ISLAND SINCE 1970 AND PRELIMINARY ASSESSMENT OF HIGH POTENTIAL HABITAT . IDENTIFICATION OF HIGH POTENTIAL HABITAT WAS BASED ON ASSESSMENT OF PREFERRED VEGETATION AND GEOLOGY AND AREAS UTILISED BY BURROW -NESTING SEABIRDS...... 12
FIGURE 2. RECORDS OF THE LORD HOWE PLACOSTYLUS IN THE SETTLEMENT AREA SINCE 1970...... 13
FIGURE 3. CURRENT RODENT CONTROL AREAS ON LORD HOWE ISLAND. CONTROL AREAS LISTED IN APPENDIX 1 AS HIGH PRIORITY OR RELEVANT FOR THE LORD HOWE PLACOSTYLUS ARE INDIVIDUALLY IDENTIFIED...... 14 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
1.0 Introduction et al. 1977; Sutherland and Ritchie 1977). The decline of the species was first noted in the 1940s (Iredale The Lord Howe Placostylus is a large terrestrial snail 1944), and the species is now listed as critically found only on Lord Howe Island. Its status has declined endangered (category CRB1+2abcde) on the 2000 from common to endangered. The aim of this recovery IUCN Red List of Threatened Species (IUCN Species plan is to protect the species in the wild in the long term Survival Commission 2000). and encourage community involvement in its conservation and recovery. P. bivaricosus cuniculinsulae is presumed extinct. The original forest cover on Blackburn Island is largely 2.0 Description and distribution cleared and no specimens have been collected there for over a century (Australian Museum 2001). The The genus Placostylus is a group of large ground- subspecies was not recorded during a targeted search of dwelling gastropods with a disjunct distribution in the Blackburn Island in 1999 (Ponder and Chapman 1999). south-west Pacific from the Solomon Islands, Fiji and P. bivaricosus etheridgei has declined in range and New Caledonia to Lord Howe Island and the northern abundance. It was considered likely to be extinct (NSW extremity of New Zealand (Abbott 1989; Parrish et al. Scientific Committee 1997; Australian Museum 2001), 1995; Ponder and Chapman 1999). This distribution but may survive as a number of small, isolated local reflects a probable Gondwanan origin (Stanisic 1981). populations, based on the recent identification of The Lord Howe Placostylus Placostylus bivaricosus hatchling snails from leaf litter collected from Little and (Gaskoin, 1855) (Family Bulimulidae) is endemic to Big Slopes in the 1970s (Ponder and Chapman 1999). Lord Howe Island, and is most closely related to New P. bivaricosus bivaricosus remains extant but is Zealand Placostylus species (P. ambagiosus, P. bollonsi endangered and has declined in range and abundance. and P. hongii) (Ponder and Chapman 1999). The Lord During a general invertebrate survey on the Island by Howe Placostylus has a pointed shell up to eight the Australian Museum in 1971 P. bivaricosus centimetres in length, medium to dark brown in colour bivaricosus was recorded at only three sites: Windy (weathering to white in older specimens) and with a Point, the east end of North Bay and the east end of thickened lip. The body colour is black. Neds Beach (Smithers et al. 1977; Australian Museum Three recent subspecies of the Lord Howe Placostylus 2001). These were the only known recent sites for the are recognised (Australian Museum 2001); P. species at the time it was listed under the TSC Act bivaricosus bivaricosus (Gaskoin, 1855), P. bivaricosus (NSW Scientific Committee 1997). cuniculinsulae (Cox, 1872) and P. bivaricosus A brief study of land snails on Lord Howe Island in etheridgei (Hedley, 1891). P. bivaricosus bivaricosus 1997 (Curtis 1998) recorded live P. bivaricosus was formerly common over the northern, lower end of bivaricosus at only two of 23 sites examined: one at Lord Howe Island from sea level to about 200 m (the North Bay and another at a new location at Blue Lagoon top of Malabar Hill). P. bivaricosus cuniculinsulae Apartments in the Settlement area. A targeted survey occurred on Blackburn (Rabbit) Island in the lagoon at funded by the NSW National Parks and Wildlife Service Lord Howe Island. P. bivaricosus etheridgei occurred in (NPWS) in 1999 (Ponder and Chapman 1999) recorded the mountains at the southern end of Lord Howe Island, live or freshly dead P. bivaricosus bivaricosus at 24 including the Erskine Valley, to an altitude of 350 m. A sites out of a total of 59 sites examined. Live P. fourth taxon, P. bivaricosus solidus (Brazier, 1889), is bivaricosus bivaricosus were also recorded in Stephens known from fossils from Pleistocene calcarenite Reserve in November 1998 (C. Haselden Lord Howe deposits on Lord Howe Island. Island Board pers. comm. 2001) and near Transit Hill in Considerable variation in shell morphology exists June 2000 (E. Brown Royal Botanic Gardens pers. within and between some extant populations of P. comm. 2001). bivaricosus bivaricosus (Ponder and Chapman 1999). The approximate locations of the sites where the Lord Similar variation in P. ambagiosus in New Zealand was Howe Placostylus has been recorded since 1970 are found to have a genetic basis (Triggs and Sherley 1993). shown in Figures 1 and 2. The majority of sites are in Preliminary examination of genetic variation in P. the Settlement area in the mid-Island lowlands. Local bivaricosus bivaricosus has indicated a likely distinction Island residents have reported that the Lord Howe between a more elongated shelled form found Placostylus was still very common in the Settlement predominantly in the northern part of the Island and a area during the 1970s (G. Wilson Lord Howe Island broader shelled form from the central part of the Island Board pers. comm. 2001), and this area is now a major (Colgan and Ponder 2001). stronghold for the species. 3.0 Current conservation status 4.0 Habitat and ecology
Historical accounts and fossil evidence indicate that the Brazier (1889) noted that the Lord Howe Placostylus Lord Howe Placostylus was formerly widespread and was abundant under cover in shady damp situations and abundant on Lord Howe Island (Brazier 1889; Smithers
NSW National Parks and Wildlife Service 1 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus on scrubby calcarenite hillsides, was sparingly The diet of the Lord Howe Placostylus is thought to be represented at higher altitudes, and appeared to avoid the fallen dead leaves of broadleaf trees (Ponder and open areas. Ponder and Chapman (1999) found live Chapman 1999). New Zealand Placostylus species feed Lord Howe Placostylus sheltering under well-developed on the fallen leaves of a range of native broadleaf tree moisture-retaining leaf litter in forest, often but not and shrub species (Parrish et al. 1995; Sherley et al. exclusively in the vicinity of Banyan trees Ficus 1998). columnaris, and mostly on calcarenite-derived soils and sandy soils. 5.0 Relevant legislation The vegetation at all recent Lord Howe Placostylus sites The Lord Howe Placostylus is listed as an endangered is either Kentia Palm Howea fosteriana evergreen species on Schedule 1, Part 1 of the Threatened Species closed forest or Greybark Drypetes australasica – Conservation Act 1995 (TSC Act). The species is not Blackbutt Cryptocarya triplinervis evergreen closed currently listed on the Commonwealth Environment forest, using the vegetation associations described and Protection and Biodiversity Conservation Act 1999 mapped by Pickard (1983), or in ecotones between these (EPBC Act). This plan proposes nomination of the two associations (Curtis 1998; Ponder and Chapman species for listing under the EPBC Act. 1999). Ponder and Chapman (1999) noted that Lord Howe Placostylus were generally sparse or absent in Lord Howe Island is administered by the Lord Howe areas developed as palm plantations, but mixed palms Island Board (LHIB) under the Lord Howe Island Act and broad-leaf forest provided good habitat. 1953 and is subject to NSW Government laws including the Environmental Planning and Assessment Act 1979 A preliminary assessment of high potential habitat for (EPA Act), TSC Act and National Parks and Wildlife the Lord Howe Placostylus is included in Figure 1. This Act 1974. recovery plan proposes further detailed assessment and identification of high potential habitat for the species. The Lord Howe Island group was listed as a World Heritage Property under the World Heritage Convention Placostylus species do not seal the shell opening in 1982. The existence of the Lord Howe Placostylus (aperture) with a mucous seal during dry conditions, as has been identified as contributing to the Island’s World does the introduced Garden Snail Cantareus aspersa Heritage values (LHIB 1999). An action will require (formerly Helix aspersa), and are therefore prone to approval from the Federal Environment Minister under desiccation (Sherley 1994). Large juveniles and adults the EPBC Act if the action has, will have, or is likely to may gain some protection from desiccation by pushing have a significant impact on the World Heritage values the front of their shell shallowly into the soil to cover of a declared World Heritage Property. the aperture (Sherley et al. 1998). Ponder and Chapman (1999) noted freshly dead shells in areas where the 6.0 Recovery plan implementation forest canopy had been damaged by drought or storms. The TSC Act requires that a government agency must The Lord Howe Placostylus lays small clutches of eggs not undertake actions inconsistent with a recovery plan. in the soil beneath leaf litter, probably during the The actions identified in this plan are primarily the warmer months, the eggs hatching into small-shelled responsibility of the LHIB and the NPWS. snails about 6.7 mm in length and 5 mm in width (Ponder and Chapman 1999). Hatchling and juvenile 6.1 Critical habitat mortality is high (Ponder and Chapman 1999). Growth rate and lifespan of the Lord Howe Placostylus are The TSC Act makes provision for the identification and unknown, but related Placostylus species in New declaration of critical habitat for species, populations Zealand reach maturity at three to five years and may and ecological communities listed as endangered. Once live for 20 years or more (Parrish et al. 1995). declared, it becomes an offence to damage critical habitat (unless the action is specifically exempted by the In areas of suitable habitat the Lord Howe Placostylus TSC Act) and a species impact statement is mandatory occurs at an average density of one live adult per 4.17 2 2 for all developments and activities proposed within m and one live juvenile per 3.03 m (Ponder and critical habitat. Identification and declaration of critical Chapman 1999), with localised densities of up to two habitat is not currently proposed for the Lord Howe live animals per square metre in appropriate Placostylus. microhabitat patches within these areas. These densities are comparable to those observed in New Zealand 6.2 Environmental assessment Placostylus species (Parrish et al. 1995). Accumulated shells of dead Lord Howe Placostylus can remain in the The TSC Act amendments to the environmental soil and leaf litter for many years and in some places assessment provisions of the EPA Act require that can occur at densities of up to 30 shells per square metre consent and determining authorities consider relevant (Ponder and Chapman 1999). recovery plans when exercising a decision-making function under Parts 4 & 5 of the EPA Act. Consent or determining authorities must consider the potential for
NSW National Parks and Wildlife Service 2 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus adverse impacts on the Lord Howe Placostylus or its now controlled (Lord Howe Island Board 1986) and has habitat when approving developments or activities, and largely ceased, although it may still be an issue at a require a species impact statement where application of smaller scale with respect to development and the Eight Part Test (s5A EPA Act) indicates a landscaping works in the Settlement area. significant effect is likely. The Ship Rat Rattus rattus was accidentally introduced The LHIB, as the primary consent authority on the to Lord Howe Island in 1918, and was prolific across Island, must consider the conservation strategy and the Island by 1930 (Billing 1999). Rats prey extensively information outlined in this plan when considering a on the Lord Howe Placostylus, particularly on juvenile proposed development or activity that may affect the snails, and are considered to be a major predator of the species. species and a significant threat to its survival (Ponder and Chapman 1999). Rats are also a major threat to This plan includes environmental impact assessment New Zealand Placostylus species. Research on rat guidelines to assist those required to prepare or review predation on P. ambagiosus in New Zealand has assessments of likely impacts on the Lord Howe demonstrated that control of rats by pulse baiting can Placostylus, including the LHIB (Appendix 2). significantly increase adult snail recruitment (Sherley et Any action not requiring approval under the EPA Act, al. 1998). Rats are not currently present on offshore and which may adversely affect the Lord Howe islands in the Lord Howe Island group, including Placostylus or its habitat, may be licensed under Part 6 Blackburn Island. of the TSC Act. New Zealand Placostylus species are preyed upon by As the Lord Howe Placostylus is listed as contributing the introduced Song Thrush Turdus philomelos and to the World Heritage values of Lord Howe Island Common Blackbird Turdus merula (Parrish et al. 1995; (LHIB 1999), any person proposing to undertake actions Sherley et al. 1998). Both of these bird species had likely to have a significant impact on the Lord Howe colonised Lord Howe Island by 1953 (Hutton 1991). Placostylus should refer the action to the Local Island residents have reported observations of Commonwealth Minister for the Environment for predation on the Lord Howe Placostylus by these bird consideration. The Minister will then decide whether the species (G. Wilson Lord Howe Island Board pers. action requires EPBC Act approval. This is in addition comm. 2001). The Common Blackbird and Song Thrush to any State or Local Government approval requirement may be significant predators of the Lord Howe specified above for the NSW EPA Act. Placostylus and this recovery plan proposes further assessment of this potential threat and the feasibility of 7.0 Management issues eradication or control of these species. Feral populations of the Pig Sus scrofa and Goat Capra 7.1 Threats and reasons for decline hircus were established on Lord Howe Island by 1851 Causes of the decline of the Lord Howe Placostylus are (Pickard 1983). Predation and habitat disturbance by likely to include habitat clearing and modification, pigs and habitat disturbance by goats were considered predation and habitat disturbance by exotic fauna serious threats to the Lord Howe Placostylus (Smithers species, and possibly herbicide and pesticide use et al. 1977). Pigs have been successfully eradicated (Iredale 1944; Smithers et al. 1977; Ponder 1997; NSW from the Island and eradication of goats is currently Scientific Committee 1997; NSW Scientific Committee underway. Following an extensive feral goat control 2000; Australian Museum 2001; Ponder and Chapman program conducted in 1999 feral goat numbers are 1999). currently at the lowest density since their introduction to the Island. Habitat clearing would have had a substantial effect on the Lord Howe Placostylus historically during Ponder and Chapman (1999) identified habitat establishment of the Settlement area, rural grazing areas disturbance and trampling of snails by Domestic Cattle and palm plantations (Ponder and Chapman 1999). P. Bos taurus and habitat disturbance and predation of bivaricosus cuniculinsulae, in particular, lost most of its eggs and hatchlings by Domestic Fowl Gallus habitat, the majority of the original Drypetes– domesticus as possible localised threats to the Lord Cryptocarya evergreen closed forest on Blackburn Howe Placostylus. Island (Pickard 1983) being replaced by grassland. The Disturbance of the leaf litter layer by nesting seabirds preliminary assessment of high potential habitat for the may adversely affect the Lord Howe Placostylus Lord Howe Placostylus (Fig. 1) indicated that 44% of (Ponder and Chapman 1999). Flesh-footed Shearwaters the previous 228.5 ha of high potential habitat for the Puffinus carneipes breed in coastal areas of Howea and species has been cleared since settlement of the Island, Drypetes-Cryptocarya evergreen closed forest on leaving 128 ha. Removal of the forest canopy results in calcarenite in the north-east of the Island, nesting in loss of leaf litter habitat and exposure of snails to burrows excavated in the sandy soil. Ponder and desiccation (Sherley et al. 1998, Ponder and Chapman Chapman (1999) noted many dead Lord Howe 1999). Clearing of native forest on Lord Howe Island is
NSW National Parks and Wildlife Service 3 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
Placostylus shells but few fresh specimens and no live threatening process under Schedule 3 of the TSC Act in specimens in active nesting areas. September 2001 (NSW Scientific Committee 2001).
Introduced weed and ornamental flora species, such as 8.2 Survey and research exotic grasses, asparagus fern, guava and crofton weed, are invading some areas of Lord Howe Placostylus Surveys for the Lord Howe Placostylus between 1970 habitat (Ponder and Chapman 1999). The potential and 1997 recorded populations at only four sites (Curtis effect of these species on habitat suitability for the Lord 1998; Australian Museum 2001). A survey in 1999 Howe Placostylus is unknown but is likely to be targeting the above four sites and additional areas of adverse. potential habitat (Ponder and Chapman 1999), together with analysis of leaf litter material collected from the Herbicides are currently used for the control of weeds in southern mountains in the 1970s and observations some areas on Lord Howe Island. The potential effect of reported by Island residents and visitors, has brought the these chemicals on the Lord Howe Placostylus is number of recent (post 1970) records of the Lord Howe unknown. Pesticides such as snail baits may be used by Placostylus to 29 known sites. landholders in some parts of the Settlement area for the control of the introduced Garden Snail. There is a strong A preliminary assessment of the genetics of extant likelihood these baits would be fatal to the Lord Howe populations of the Lord Howe Placostylus was Placostylus. undertaken in 2001 with joint funding provided by the NPWS and Australian Museum (Colgan and Ponder Actions for the management of threats to the Lord 2001). The results of the study suggested two genetic Howe Placostylus are detailed in this plan. clades with distinctive shell morphology in the northern 7.2 Social and economic consequences and central parts of the Island. The study recommended that conservation measures such as rat control Costs of implementing the actions identified in this encompass populations from each of the four main areas recovery plan can be located in Table 2. Implementation of extant populations (behind North Beach, the eastern has been costed at $148 500 (priority 1), $163 000 part of the Settlement area, western part of the (priorities 1 and 2) and $177 000 (priorities 1, 2 and 3). Settlement area, and the area south-east of the airport) in order to conserve maximum genetic diversity of the This recovery plan requires consideration of potential species (Colgan and Ponder 2001). impacts on the Lord Howe Placostylus by consent and determining authorities considering activities in areas of 8.3 Rat control known or potential habitat of the species. Control of rats on the Island has been undertaken Implementation of this recovery plan is anticipated to periodically over the last 70 years, beginning in the late have a positive flow-on with economic benefits to the 1920s with a bounty on rat tails. A regular control community through local acquisition of materials and program using the anticoagulant poison warfarin has labour and by contributing to an increased public been running since 1986 (Harden and Leary 1992). awareness of the Island’s significant natural heritage values. A review of the rodent control program for the LHIB by Billing (1999) made recommendations designed to 7.3 Biodiversity benefits increase the effectiveness of the program, including expansion of rat baiting grids to encompass 4 ha areas. The conservation of threatened invertebrate species is a A revised rodent control program incorporating these relatively new issue in NSW. Through awareness of the recommendations was commenced by the LHIB in status of the Lord Howe Placostylus the profile of other September 2000, with a number of baiting areas invertebrate species will be raised in the general expanded to 4 ha in size. In each of these areas bait community. This in turn will lead to greater stations are set in grids of 6 stations x 6 stations at 40 m opportunities for the conservation of threatened species intervals, and baiting occurs 4 times per year. The LHIB and increased protection of biodiversity. is also continuing baiting at a number of existing baiting 8.0 Previous actions undertaken sites which remain at less than 4 ha in area. The location and extent of current rat baiting areas in the rodent control program on Lord Howe Island are shown in 8.1 Listing under TSC Act Figure 3. The current total cost of rodent control on The Lord Howe Placostylus was listed as an endangered Lord Howe Island is approximately $50 000 per annum. species under Schedule 1 Part 1 of the TSC Act in April In 2001 the LHIB contracted the Endangered Species 1997 (NSW Scientific Committee 1997). Predation Recovery Council to prepare a feasibility study for the from the Ship Rat on Lord Howe Island was listed as a total eradication of rodents on Lord Howe Island. key threatening process under Schedule 3 of the TSC Act in May 2000 (NSW Scientific Committee 2000). This recovery plan proposes continuation of targeted rat Clearing of native vegetation was listed as a key control at key sites to protect Lord Howe Placostylus
NSW National Parks and Wildlife Service 4 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
populations (identified in Appendix 1) and supports in · Objective 1: to assist identification of habitat for the principle the eradication of rodents from the Island. This Lord Howe Placostylus. plan also proposes monitoring the status of both · Objective 2: to assist identification of additional protected and unprotected Lord Howe Placostylus populations of the Lord Howe Placostylus. populations to provide further information concerning the significance of rat predation as a threat to the species · Objective 3: to improve the protection and and the effectiveness of rat control measures. management of the Lord Howe Placostylus and its habitat. 8.4 Pig and goat control · Objective 4: to identify and conserve the maximum Eradication of feral pigs on Lord Howe Island was level of genetic diversity in the species. undertaken by the LHIB in the late 1970s and early · Objective 5: to identify and ameliorate current 1980s. Eradication of feral goats commenced in 1999. threats to the Lord Howe Placostylus. The LHIB is continuing to monitor and eradicate feral goats in the Southern Mountains area of the Island. · Objective 6: to support and coordinate research into the Lord Howe Placostylus relevant to its recovery. 8.5 Habitat protection · Objective 7: to encourage community awareness of Areas providing habitat for P. bivaricosus bivaricosus the status of the Lord Howe Placostylus and threats and P. bivaricosus etheridgei on Lord Howe Island, and to its survival, and support community involvement areas previously providing habitat for P. bivaricosus in its recovery. cuniculinsulae on Blackburn Island, are protected in the · Objective 8: to reassess recovery program priorities Permanent Park Preserve (zone 3(a)) and Environment based upon information generated during the life of Protection areas (zone 3(d)) (LHIB 1986). These areas the plan. of habitat include sites with recent records of P. bivaricosus bivaricosus at North Bay, Old Settlement 11.0 Recovery performance criteria Beach and Neds Beach, and Big Slope and Little Slope where P. bivaricosus etheridgei was collected in the Recovery performance criteria are listed below. 1970s (Ponder and Chapman 1999). · Criterion 1: areas of high potential habitat for the The Lord Howe Island Regional Environmental Plan Lord Howe Placostylus are identified. 1986 (LHIB 1986) and Lord Howe Island Group World Heritage Property draft Strategic Plan for Management · Criterion 2: the identification of additional (LHIB 1999) also provide a level of protection for areas populations of the Lord Howe Placostylus through of habitat through planning controls and management scientific survey and community awareness is strategies and actions. supported. · Criterion 3: known and potential habitat of the Lord 8.6 Community awareness Howe Placostylus is appropriately managed and the The Australian Museum provides information on the protection and management of populations of the Lord Howe Placostylus and other threatened land snails species are improved. to the general public on its invertebrate zoology internet · Criterion 4: the level of genetic variation within and web site (Australian Museum 2001). The NPWS and between extant populations is assessed and this LHIB raised community awareness of the Lord Howe information is used in determining management Placostylus through local and state media during public priorities for extant populations. exhibition of the draft recovery plan. · Criterion 5: actions are successfully undertaken to 9.0 Species’ ability to recover control or manage identified threats.
Given the current information base, including · Criterion 6: appropriate research is initiated and coordinated. experience with related species in New Zealand, the Lord Howe Placostylus can be expected to recover if · Criterion 7: community awareness of the status of identified threats can be controlled. the Lord Howe Placostylus and threats to its survival, and community participation in its 10.0 Recovery objectives conservation and recovery, are increased. The overall objective of this recovery plan is to protect · Criterion 8: recovery program priorities are and recover the Lord Howe Placostylus in the wild in reviewed annually during the life of the plan. the long term. Specific objectives for the first five years of this recovery plan are listed below.
NSW National Parks and Wildlife Service 5 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
12.0 Recovery actions Outcome
Recovery actions to be undertaken over the next five Increased knowledge of current distribution of habitat and populations, determination of the extent of any years to achieve the identified specific recovery objectives are listed below. Linkages with specific impact of rats on the species’ status, and collection of objectives and performance criteria are identified for additional information to assist in the conservation and recovery of the species. Note: Actions 1 to 5 may be each action. undertaken in coordination as a single project. 12.1 Survey and research 12.2 Protection of extant populations and habitat 1. Scientific identification and survey of areas of high 8. Rat baiting program to continue at the 11 high potential habitat in the southern mountains area of Lord Howe Island, including Big Slope and Little priority rat baiting areas identified in Appendix 1 of Slope, to identify any extant populations of P. this plan as a minimum for the protection of key Lord Howe Placostylus populations. Continued rat bivaricosus etheridgei. (Objectives 1 and 2/Performance criteria 1 and 2). control in additional baiting areas relevant to the Lord Howe Placostylus (Appendix 1) should also 2. Long-term monitoring established at selected Lord be supported. (Objectives 3-5/Performance criteria Howe Placostylus sites to identify any changes in 3-5). the status of the species. A minimum of eight sites to be monitored: four sites within areas where rat 9. Details concerning recent and historic sites of the Lord Howe Placostylus from museum records and control is undertaken (experimental group) and four sites with no rat control (control group). This will other sources to be entered on the NPWS Wildlife enable assessment of the extent of any impact of Atlas database and provided to the LHIB. (Objective 1 and 3/Performance criteria 1 and 3). rats on the status of the Lord Howe Placostylus. (Objectives 3 and 5/Performance criteria 3 and 5). 10. Maps of high potential habitat for the Lord Howe 3. Initiate a study of the impact of the Common Placostylus to be prepared and provided to the LHIB to assist with land management and Blackbird and Song Thrush on the Lord Howe Placostylus and the feasibility of eradicating these environmental planning and assessment matters. bird species from Lord Howe Island. (Objectives 5 Map derivation to include occurrence of calcarenite-derived and sandy soils, occurrence of and 6/Performance criteria 5 and 6). H. fosteriana evergreen closed forest and Drypetes- 4. Support for research concerning threats to the Lord Cryptocarya evergreen closed forest, and Howe Placostylus and actions to control these distribution of recent and historical Lord Howe agents, with particular reference to predation by Placostylus records. (Objectives 1-3/Performance introduced bird species and rats, habitat degradation criteria 1-3). by exotic weeds, and impacts of herbicide and 11. The LHIB and other approval authorities pesticide usage. (Objectives 5 and 6/Performance criteria 5 and 6). undertaking Eight Part Tests (s 5A EPA Act) for proposed developments and activities in or near 5. Support for and coordination of research into the areas of known or potential habitat for the Lord ecology and lifecycle of the Lord Howe Placostylus Howe Placostylus are to include consideration of relevant to the conservation and recovery of the potential impacts on the species and its habitat. species. (Objective 6/Performance criterion 6). Environmental Impact Assessment Guidelines have been prepared to assist consideration (Appendix 2). 6. Support for further genetics research to investigate (Objective 3/Performance criterion 3). the relationship between shell shape and genetic differentiation in the Lord Howe Placostylus and to Outcome provide clearer delineation of the distribution of different clades. (Objectives 4 and 6/Performance Increased awareness and protection of the Lord Howe criteria 4 and 6). Placostylus and its habitat. 7. Research and field survey projects involving the 12.3 Commonwealth listing Lord Howe Placostylus requiring licensing under the TSC Act will be required to observe the 12. Nomination of the Lord Howe Placostylus as an guidelines provided in Appendix 3, to ensure that endangered species under the Commonwealth the work undertaken does not further threaten the EPBC Act. (Objectives 3 and 7/Performance survival of the species or a population of the criteria 3 and 7). species. (Objective 3/Performance criterion 3). Outcome Recognition at national level of the conservation status of the species.
NSW National Parks and Wildlife Service 6 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
12.4 Community awareness and involvement Outcome
13. Preparation and distribution of a brochure Increased community awareness of the Lord Howe concerning the Lord Howe Placostylus to residents Placostylus and encouragement of community and tourists on Lord Howe Island. The brochure involvement in its conservation and recovery. will be designed to include the following 12.5 Ex situ conservation measures components: · provide information on the status and 17. Establishment of a captive breeding program for the identification of the Lord Howe Placostylus Lord Howe Placostylus as outlined by Ponder and and the habitat requirements of the species; Chapman (1999). This will involve construction of a number of 2 m x 2 m rat-proof pens provided with · promote the Lord Howe Placostylus as a shade and appropriate leaf litter in which breeding flagship species for invertebrate and populations of Lord Howe Placostylus can be biodiversity conservation on Lord Howe established and maintained. Maintenance Island; requirements will involve replenishment of leaf · encourage the identification and reporting of litter and monitoring of size of reared snails. Adult additional populations of the Lord Howe snails reared in the program are to be released back Placostylus by the community; into original natural populations to maintain genetic integrity. (Objectives 3-5/Performance criteria 3- · provide information concerning threats or 5). potential threats to the Lord Howe Placostylus including removal or modification of habitat, 18. Regeneration of an area of approximately one spread of weed and ornamental plant species hectare of Drypetes-Cryptocarya evergreen closed into native forest, use of herbicides and forest on the northern side of Blackburn Island pesticides, and uncontrolled access to native (incorporating existing remnant native vegetation). forest by domestic stock and fowl; and (Objectives 3 and 5/Performance criteria 3 and 5). · provide information to encourage protection of Outcome the species and its habitat. (Objectives 1-3, 5 Augmentation of natural populations by protecting and 7/Performance criteria 1-3, 5 and 7). snails from rat predation during vulnerable juvenile 14. Preparation of a permanent display in the Lord stage, and creation of a rat-free area of habitat to be Howe Island Visitors Centre/Museum to promote used as a release site in the event that translocation of awareness of the status of the Lord Howe Lord Howe Placostylus is considered necessary at a Placostylus, to provide information regarding future date. (A broader outcome of action 18 will be the threats to the species and the protection and provision of rat-free closed forest habitat for a range of management of the species and its habitat, and to additional threatened and protected species on Lord raise the general profile of invertebrate Howe Island.) conservation issues. Components of the display 12.6 Recovery team should include examples of fresh and old shells, a life cycle chart, information on preferred habitat, 19. Formation of a Lord Howe Island recovery team why the species is considered endangered and with representatives from the LHIB, Lord Howe current threats, and a brief outline of other land Island community, NPWS and Australian Museum snails on the Island and their general function in the to oversee and coordinate implementation of this ecosystem. (Objectives 1-3, 5 and 7/Performance and other recovery plans on the Island. Recovery criteria 1-3, 5 and 7). team to convene on a six monthly basis. (Objectives 15. High profile media publicity concerning the Lord 1-7/Performance criteria 1-7). Howe Placostylus and its conservation and 20. Annual review of recovery plan priorities based on recovery will be sought over the life of the recovery information generated through survey and research. plan. (Objectives 2, 3, 5 and 7/Performance criteria (Objective 8/Performance criterion 8). 2, 3, 5 and 7). Outcome 16. The NPWS will liaise with the Australian Museum on a maximum six monthly basis to assist the Coordination and ongoing evaluation of implementation Museum in maintaining up to date information of the Lord Howe Placostylus recovery plan and other concerning the Lord Howe Placostylus on the recovery plans on Lord Howe Island. Museum’s invertebrate zoology internet web site. 13.0 Implementation (Objectives 1-3, 5 and 7/Performance criteria 1-3, 5 and 7). Table 1 allocates responsibility for the implementation of recovery actions specified in this
NSW National Parks and Wildlife Service 7 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus plan to relevant government agencies for a period of Red List of Threatened Species. IUCN Species five years from the time this recovery plan is Survival Commission, Gland, Switzerland. adopted. Iredale, T. (1944). The land Mollusca of Lord Howe 14.0 Preparation details Island. Australian Zoologist 10(3): 299-334.
This recovery plan was prepared by Michael Lord Howe Island Board (1986). Lord Howe Island Murphy, NPWS Threatened Species Officer, Regional Environmental Plan 1986. Conservation Programs and Planning Division, NPWS Northern Directorate, in consultation with Lord Howe Island Board (1999). Lord Howe Island the LHIB. Background information and assistance World Heritage Property Strategic Plan for was provided by Dr Winston Ponder (Australian Management. Museum) and Dr John Stanisic (Queensland NSW Scientific Committee (1997). Final determination Museum). Figures in the plan were prepared with the to list Placostylus bivaricosus as an endangered species assistance of Katrina McKay, Jill Smith and Aleks on Schedule 1, Part 1 of the Threatened Species Maric. Conservation Act 1995. Gazettal date 4/4/97. 15.0 Review date NSW Scientific Committee (2000). Final determination to list predation from the Ship Rat Rattus rattus on Lord This recovery plan will be reviewed within five Howe Island as a key threatening process on Schedule 3 years of the date of publication. of the Threatened Species Conservation Act 1995. 16.0 References Gazettal date 12/5/00. NSW Scientific Committee (2001). Final determination Abbott, R. T. (1989). Compendium of Landshells. to list clearing of native vegetation as a key threatening American Malacologists Inc., Burlington MA. process on Schedule 3 of the Threatened Species Australian Museum (2001). Threatened and Conservation Act 1995. Gazettal date 21/9/01. Endangered Landsnail species. Australian Museum Parrish, R., Sherley, G. and Aviss, M. (1995). Giant Invertebrate Zoology Internet site Land Snail Recovery Plan Placostylus spp., Paryphanta
NSW National Parks and Wildlife Service 8 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
Smithers, C. McAlpine, D., Colman, P. and Gray, M. 17.0 Acronyms used in this document (1977). Island Invertebrates. Pages 23-26 in Lord Howe Island. Published by the Australian Museum, Sydney. EPA Act Environmental Planning and Assessment Act 1979 Stanisic, J. (1981). Land Mollusca in Lord Howe Island. A summary of current and projected scientific and EPBC Act Environment Protection and environmental activities. Occasional Reports of the Biodiversity Conservation Act 1999 Australian Museum No. 1. Australian Museum, Sydney IUCN International Union for the NSW. Conservation of Nature Sutherland, L. and Ritchie , A. (1977). Defunct LHIB Lord Howe Island Board volcanoes and extinct horned turtles. Pages 7-12 in Lord NPWS National Parks and Wildlife Service Howe Island. Published by the Australian Museum, Sydney. NSW New South Wales
Triggs, S. and Sherley, G. (1993). Allozyme genetic TSC Act Threatened Species Conservation Act diversity in Placostylus land snails and implications for 1995 conservation. New Zealand Journal of Zoology 20: 19- 33.
NSW National Parks and Wildlife Service 9 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
18.0 Implementation Tables
Table 1: Responsibility for implementation, timing and priority of recovery actions. Priority is categorised as 1 (essential), 2 (highly desirable) or 3 (desirable).
Description Responsibility for Timeframe Priority implementation 1
Survey and research Action 1: survey southern mountains NPWS and LHIB Year 1 1 Action 2: monitoring NPWS and LHIB Years 2 and 4 1 Action 3: study of bird predation NPWS and LHIB Years 1 and 2 1 Action 4: support research into threats NPWS and LHIB Years 2 and 3 1 Action 5: ecological research NPWS and LHIB Years 2 and 3 2 Action 6: genetics research NPWS and LHIB Year 3 3 Action 7: research guidelines NPWS Life of plan 2 Protection of populations and habitat Action 8: rat control at key sites LHIB Life of plan 1 Action 9: record management NPWS and Australian Life of plan 1 Museum Action 10: map potential habitat NPWS Year 1 1 Action 11: environmental planning LHIB and other approval Life of plan 1 authorities Commonwealth listing Action 12: EPBC Act nomination NPWS Year 1 1 Community involvement Action 13: community brochure NPWS and LHIB Year 1 1 Action 14: museum display NPWS and LHIB Year 1 2 Action 15: media NPWS and LHIB Life of plan 2 Action 16: Museum internet web site NPWS and Australian Life of plan 2 Museum Ex situ conservation measures Action 17: captive breeding LHIB and NPWS Years 2 to 5 2 Action 18: Blackburn Is. Regeneration LHIB and NPWS Years 1 to 5 3 Recovery team Action 19: recovery team NPWS and LHIB Life of plan 1 Action 20: annual review Recovery team Life of plan 1
1 Organisation with primary responsibility for action listed first.
NSW National Parks and Wildlife Service 10 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
Table 2: Estimated costs of implementing recovery actions. Costed actions are subject to funding availability unless otherwise noted. Estimates do not include Goods and Services Tax.
Recovery action Year of implementation Funding responsibility 1 2 3 4 5 Total NPWS LHIB Survey and research Action 1: survey southern Mts 10 000 - - - - $10 000 · 10 000 # Action 2: monitoring - 5000 - 5000 - $10 000 · 10 000 # Action 3: study of bird predation 5000 5000 - - - $10 000 · 10 000 # Action 4: research into threats - 5000 3000 - - $8000 · 8000 # Action 5: ecological research - 5000 3000 - - $8000 · 8000 # Action 6: genetics research - - 7000 - - $7000 · 7000 - Action 7: research guidelines Ö Ö Ö Ö Ö - - - Protection of populations & habitat Action 8: rat control at key sites 20 000 20 000 20 000 20 000 20 000 100 000 - 100 000
Action 9: record management y y y y y - - - Action 10: map potential habitat 4000 - - - - $4000 4000 - Action 11: environmental Ö Ö Ö Ö Ö - - - planning Commonwealth listing Action 12: EPBC Act nomination y ------Community involvement Action 13: community brochure 1500 - - - - $1500 1500 - Action 14: museum display 2000 - - - - $2000 2000 - Action 15: media y y y y y - - - Action 16: Museum internet web y y y y y - - - site Ex situ conservation measures Action 17: captive breeding - 3000 500 500 500 $4500 · 2000 · 2500 Action 18: Blackburn Is. 3000 2000 1000 500 500 $7000 3500 3500 Regeneration Recovery team Action 19: recovery team 1 1000 1000 1000 1000 1000 $5000 5000 # Action 20: annual review Ö Ö Ö Ö Ö - - - Total cost of 46 500 46 000 35 500 27 000 22 000 177 000 71 000 106 000 implementing plan Ö No direct cost; however, action must be considered by relevant public authority. y Costs covered by NPWS core duties. # LHIB to assist with transport and accommodation costs and to provide staff assistance. · NPWS and LHIB to seek to undertake action as cooperative project with research institution with appropriate expertise, such as the Australian Museum. 1 Estimated as component contribution to multi-species Lord Howe Island recovery team.
NSW National Parks and Wildlife Service 11 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
LEGEND
# Lord Howe Placostylus (recent records) Malabar High potential habitat f or $T Hill Lord Howe Placostylus (preliminary identification) # # # # Permanent Park Preserve # # # # # # # North # # ### Bay # Settlement ## # # Area # # # #
Blackburn T$ Transit Hill Island
# Airport
Intermediate $T Hill
Mount Lidgbird $T (777 m)
Erskine Valley Little Slope
Big # $T # Slope
N Mt Gower
W E (875m)
S
0 0.5 1 1.5 2 Kilometres
Figure 1. Records of the Lord Howe Placostylus on Lord Howe Island since 1970 and preliminary assessment of high potential habitat. Identification of high potential habitat was based on assessment of preferred vegetation and geology and areas utilised by burrow-nesting seabirds.
NSW National Parks and Wildlife Service 12 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
# # # # # # # # # #
### # # # # # # # # #
#
LEGEND
# Lord Howe Placostylus (recent records) Cadastre
Permanent Park Preserve
N
W E
S
0 0.25 0.5 0.75 1 Kilometres
Figure 2. Records of the Lord Howe Placostylus in the Settlement area since 1970.
NSW National Parks and Wildlife Service 13 Approved Recovery Plan Lord Howe Placostylus Placostylus bivaricosus
LEGEND
Permanent Park Preserve
Rat baiting areas 3 High priority Relevant 4 2 Other 5 1 8 9 11
6 10
7 12 13
14 Id Name No. 1 North Bay 1 2 North Bay 2 3 Battern Flats 15 4 Neds Beach 5 Old Settlement 6 Lagoon Foreshore North 7 Lagoon Foreshore South 8 Stevens Reserve 9 Stevens Loop 10 Bowker Ave 11 Middle Beach 12 Transit Hill 13 Blinky Beach 14 Dump 15 Mully Drive 16 Big Slope 1 17 Big Slope 2 18 Little Slope
18
17 16 N
W E
S
0 0.5 1 1.5 2 Kilometres
Figure 3. Current rodent control areas on Lord Howe Island. Control areas listed in Appendix 1 as high priority or relevant for the Lord Howe Placostylus are individually identified.
NSW National Parks and Wildlife Service 14 Appendix 1: Priority rat baiting areas for the Lord Howe Placostylus
Note: An assessment of the spatial relationship between current rat baiting areas, known recent Lord Howe Placostylus sites and preliminarily identified high potential habitat for the Lord Howe Placostylus was undertaken to identify priority baiting areas for the conservation and recovery of the Lord Howe Placostylus. The recommendations of Colgan and Ponder (2001) concerning protection of maximum genetic diversity of the species were also considered. The following 11 rodent control areas have been identified as high priority for the conservation and recovery of the Lord Howe Placostylus. They include sites from each of the four main areas in the mid to north of the Island identified by Colgan and Ponder (2001), as well as one of the sites where the species was most recently recorded in the Southern Mountains area (Ponder and Chapman 1999). Additional rat baiting areas relevant to the Lord Howe Placostylus are also identified.
Baiting area Area of Island Grid Recent record High potential size of live or fresh snail habitat (ha) snails (preliminarily identification) High priority areas North Bay 1 Northern hills 6.73 X X North Bay 2 Northern hills 6.51 X X Neds Beach Eastern Settlement 5.02 X X area Middle Beach Eastern Settlement 3.31 X X area Stevens Loop Eastern Settlement 4.92 X X area Transit Hill Eastern Settlement 5.83 (nearby) X area Stevens Reserve Western Settlement 4.04 X X area Lagoon Foreshore North Western Settlement 2.01 X X area Bowker Avenue Western Settlement 4.89 X X area Dump South-east of 1.81 X X airport Big Slope 2 Southern 5.27 ? X Mountains Additional relevant areas Batten Flats Northern hills 5.73 X - Old Settlement Northern hills 0.68 X X Blinky Beach Eastern Settlement 4.26 - X area Mully Drive South-east of 2.67 - X airport Lagoon Foreshore South Western Settlement 0.49 - X area Little Slope Southern 4.49 ? X Mountains Big Slope 1 Southern 2.54 ? X Mountains
NSW National Parks and Wildlife Service 15 Appendix 2: Environmental Impact Assessment Guidelines
Lord Howe Placostylus Placostylus bivaricosus (Gaskoin, 1855) Status: Endangered species
These guidelines have been prepared to assist persons (Cryptocarya triplinervis) evergreen required to prepare or review assessments of likely closed forest, typically but not exclusively on impacts on the Lord Howe Placostylus. The calcarenite-derived soils or sandy soils. Live snails guidelines will assist in the following: shelter under or within leaf litter on the ground. Areas in the vicinity of Banyan trees (Ficus columnaris) · preparation of environmental impact appear to be particularly favoured habitat. assessment reports, Statements of Environmental Effects and Species Impact It is recommended that any area supporting evergreen Statements by proponents of developments or closed forest on calcarenite-derived soils or sandy activities pursuant to the Environmental soils be considered as potentially harbouring the Lord Planning and Assessment Act 1979; Howe Placostylus no matter how small or degraded it might appear, especially if there is any sort of leaf · review of environmental reports by consent and litter layer present. determining authorities; and The shell of the Lord Howe Placostylus can remain in · preparation of licence applications under the the leaf litter for extended periods following the death Threatened Species Conservation Act 1995 of the animal, and in some areas can be found at (TSC Act). densities of over 30 shells per square metre. Live animals are less common, occurring at average The guidelines should be read in conjunction with the densities of about one adult per four square metres in NPWS Information Circular No. 2: Threatened suitable habitat. Likely presence of the species at a Species Assessment under the EP&A Act: The ‘8 Part site can most easily be determined by searching for Test’ of Significance (November 1996). empty shells or shell fragments. Survey Searches for shell material can be undertaken year Field survey and habitat assessment for the Lord round. However, surveys to locate active live animals Howe Placostylus should be undertaken by persons are best undertaken at night during warm, wet with suitable demonstrated experience in land snail weather. Live animals can also be found by day by surveys and land snail identification. searching in the leaf litter. The minimum time required to search for fresh shell material or live Field surveys and collection of specimens for animals will depend on the size and amount of identification purposes may result in harm to the Lord potential habitat present within the site being Howe Placostylus or damage to its habitat, and assessed. However, it is suggested that for small sites accordingly should be licensed under the TSC Act. (less than 0.5 ha) at least three hours be spent The Lord Howe Placostylus recovery plan (October searching and then scaled up appropriately for larger 2001) includes collection guidelines for threatened areas. land snail surveys (Appendix 3). These guidelines have been designed to facilitate the timely licensing It should be noted that the presence of one or more of land snail survey and research licence applications individuals would generally indicate the presence of under the TSC Act, whilst ensuring that licensed further individuals within the site. In addition the activities will not further threaten the survival of presence of empty shells, particularly fresh shells threatened land snail species or populations of these with an intact periostracum (colouring), should be species. treated as indicating the likely presence of living individuals. Live animals are often retracted well Current knowledge indicates that extant populations inside the shell but can usually be distinguished from of the Lord Howe Placostylus are restricted to the old empty shells by the less worn periostracum, northern, lower end of Lord Howe Island, from smooth reddish lining inside the shell aperture immediately south-east of the airport to North Bay, (opening) and heavier weight. although small populations may survive in the southern Mountains. All recent records of the Lord Once Lord Howe Placostylus shells or live animals Howe Placostylus have been from either Kentia Palm have been recorded on a site, or when habitat (Howea fosteriana) evergreen closed forest or assessment suggests suitable potential habitat is Greybark (Drypetes australasica) – Blackbutt present, further assessment of the distribution and
NSW National Parks and Wildlife Service 16 Appendix 2: Environmental Impact Assessment Guidelines extent of habitat on the site (and adjacent to the site if of habitat should include consideration of the access is possible) should be undertaken. following: Adult Lord Howe Placostylus are readily identifiable, i) any area of habitat known to support the species; with a pointed shell up to 8 cm in length; however, ii) the size and extent of an area of potential habitat; juvenile snails may be easily confused with other species and generally require expert identification. iii) whether an area of potential habitat has vegetation communities largely unaffected by Life cycle of the species disturbances such as weed invasion; Part (a) of the eight part test asks whether the life iv) whether the area is at the edge of the species’ cycle of the species is likely to be disrupted such that range; or a viable local population of the species is likely to be placed at risk of extinction. Very little is currently v) the long term security of the area. known about the biology and life history of the Lord Where an area of potential habitat is assessed as Howe Placostylus. It lays small clutches of round being significant by one or more of the above criteria, eggs in the soil below leaf litter, probably during the warmer months, the eggs hatching into small snails either a targeted survey for the Lord Howe Placostylus at the site should be undertaken, or the measuring about 6.7 mm in length and 5 mm in area may be assumed to be known habitat for the width. Hatchling and juvenile mortality is high. The species is herbivorous and is thought to feed on leaf purposes of the assessment. litter. It is generally active at night, particularly Regional distribution of the habitat during or following rain. Nothing is currently known about rates of fecundity, length of life span, dispersal The Lord Howe Placostylus is restricted to Lord patterns and over what distances individuals can Howe Island. move. Related species in New Zealand reach maturity Isolation/fragmentation at three to five years and may live for 20 years or more. Part (d) of the eight part test asks whether a development or activity might isolate populations The life cycle of the Lord Howe Placostylus is such such that they become no longer viable (such as that if the proposed development or activity causes through inbreeding depression). Thus the the destruction of all the available habitat present development need not directly impact on a within the site then the local population will most population, but merely separate it from others by likely be lost as there is little potential to recolonise. preventing movement of animals. However, if sections of the site are to be left as habitat, then the impacts of factors such as changes to The Lord Howe Placostylus was formerly widespread microclimate, increased risk of weed invasion, fire over Lord Howe Island but is now apparently and introduced predators will have to be addressed. restricted to the northern, lower end of the Island, with the majority of records in the Settlement area. Viable local population of the species Many of the populations of this species may already It is currently not known what number of individuals be effectively isolated from others, except where they constitutes a viable population for the Lord Howe exist within the same forest remnant or similar Placostylus but it is not considered to be large. It is immediately adjacent locations. recommended that, in accordance with the As dispersal behaviour and ability are presently precautionary principle, populations are considered poorly known, it is difficult to determine what type of viable unless proven otherwise. development may isolate populations that are Endangered populations currently interacting with others. As a precautionary approach, developments which will result in the Part (b) of the eight part test asks whether the fragmentation of evergreen closed forest habitat areas viability of an endangered population is likely to be should be considered as likely to isolate Lord Howe significantly compromised. This question relates to Placostylus populations. populations listed under schedule 1 part 2 of the TSC Act, and does not apply to the Lord Howe Critical habitat Placostylus. Part (e) of the eight part test asks whether critical A significant area of habitat habitat will be affected. There is presently no critical habitat listed for the Lord Howe Placostylus. The Part (c) of the eight part test asks whether a NPWS Register of critical habitat should be significant area of known habitat is to be modified or consulted to obtain information on the current status removed. Based on the current understanding of the of critical habitat for the species. distribution and abundance of the Lord Howe Placostylus, assessment of the significance of an area
NSW National Parks and Wildlife Service 17 Appendix 2: Environmental Impact Assessment Guidelines
Adequacy of representation in conservation The TSC Act currently lists “clearing of native reserves or other similar protected areas vegetation” as a key threatening process. The Lord Howe Placostylus recovery plan identifies loss of Part (f) of the eight part test asks whether the species habitat as another threat to the recovery of the or its habitat is adequately conserved in the region. species, particularly in the Settlement area. Recently recorded extant populations of the Lord Consideration should be given to whether a Howe Placostylus occur in the Permanent Park development or activity proposal may require Preserve in the north of the Island at North Bay and clearing of native vegetation providing habitat for the Old Settlement Beach. Records of the species dating Lord Howe Placostylus. from the 1970s from the Big Slope and Little Slope areas in the southern Mountains are also within the Schedule 3 of the TSC Act should be consulted to Permanent Park Preserve. The majority of recent determine whether other relevant key threatening records, however, are outside the Island’s formal processes are listed. reserve system, with many occurring in the Processes that are generally considered by the Settlement area where they may be at risk from scientific community as being detrimental to a development. Given the distribution and likely species or its habitat, and which are relevant to the genetic diversity within the Lord Howe Placostylus, Lord Howe Placostylus, include habitat clearance the current reserve system does not represent an and/or modification, fire, weed invasion and adequate coverage of the species, particularly in the introduction of feral predators such as rats and birds. mid-Island lowlands which is now the species’ stronghold. The NPWS Atlas of NSW Wildlife and Limit of known distribution Museum records should be consulted for current Part (h) of the eight part test asks whether the species information on records of the species in conservation is at the limit of its known distribution. The Lord reserves or other similar protected areas. Howe Placostylus occurs only on Lord Howe Island. Threatening processes The most northerly recent record of the species is at North Bay and the most southerly immediately south- Part (g) of the eight part test asks the development or east of the airport. Small populations may also activity is a threatening process. The TSC Act survive in the southern Mountains area. The NPWS currently lists “predation from the Ship Rat on Lord Atlas of NSW Wildlife and Museum records should Howe Island” as a key threatening process. The Lord be consulted for current information on the Howe Placostylus recovery plan identifies rat distribution of records. predation as a key threat to the species. Consideration should be given to whether a development or activity proposal may increase the risk of predation by rats.
For Further Information contact National Parks and Wildlife Service Northern Directorate Threatened Species Unit, Locked Bag 914 Coffs Harbour NSW 2450. Phone (02) 66515 946.
REFERENCES National Parks and Wildlife Service (2001). Lord Howe Placostylus Placostylus bivaricosus recovery plan. NPWS, Hurstville, NSW. Australian Museum (2001). Threatened and Endangered Landsnail species – Placostylus bivaricosus. http://www.austmus.gov.au/science/division/invert/mal/endangered/placostylus.htm
IMPORTANT DISCLAIMER The NSW National Parks and Wildlife Service and the editor expressly disclaim all liability and responsibility to any person, whether a purchaser or reader of this document or not, in respect of anything done or omitted to be done by any person in reliance upon the contents of this document although every effort has been made to ensure that the information presented in this document is accurate and up to date.
NSW National Parks and Wildlife Service 18 Appendix 3: Guidelines for the Collection of Land Snails for identification and Research Purposes
General Guidelines
· Any unnecessary damage to sites is to be avoided. Beyond any existing formed roads, access to sites will be by foot. No repeat collections from populations sampled within five years will be conducted, unless it is part of a specific program approved by NPWS. · Rocks, logs and other potential refuge sites are to be returned to their original position immediately after searching. · When collecting genetic material, a tissue sample shall be taken rather than a whole animal, unless the collection of the animal is part of a program approved by NPWS. When taking a tissue sample, it must be collected in a manner that does not compromise the survival of the specimen. · For the purposes of live study and/or photography, one live individual from any discrete population may be held in captivity for up to five days, after which time the individual must be released at the point of capture. · Any empty shells may be collected as voucher material, and are to be used wherever possible in preference to vouchering of live animals. · For the purposes of collecting live specimens to be permanently retained as vouchers or for research purposes, the following prescriptions will apply:
- Where less than 1% of the available potential habitat at a site is surveyed, a minimum of three live animals or recent shells/fragmented shells must be located before one specimen can be taken.
- Where between 1 and 25% of the available potential habitat at a site is surveyed, a minimum of five live animals or recent shells/fragmented shells must be located before one specimen can be taken.
- Where between 25 and 75% of the available potential habitat at a site is surveyed, a minimum of ten live animals or recent shells/fragmented shells must be located before one specimen can be taken.
- Where more than 75% of the available potential habitat at a site is surveyed, a minimum of 15 live animals or recent shells/fragmented shells must be located before one specimen can be taken. · Juvenile animals are to be vouchered in preference to adult animals. · No more than two live individuals from any discrete population will be collected for voucher purposes, unless the collection of additional specimens has been specifically approved by NPWS. · Prior to commencing any collecting on lands controlled by the NPWS, permission will be obtained from the relevant NPWS Regional or Area Office. · Prior to commencing any collecting on other lands permission should be obtained from the relevant owner or land manager.
Data Records
· Once identification has been confirmed, any records of threatened species will be provided to the NPWS in a format appropriate for entry into the NPWS Atlas of NSW Wildlife. · Any person who becomes aware of first species records for NSW or of populations considered likely to extend the known range of any species is to provide such information to the NPWS within three months of becoming aware of the new information. · Within twelve months from the date of collection of a voucher specimen or specimens, the Licensee must lodge the specimen(s) with a recognised collection.
Note
· If special collections, eg. additional voucher specimens, are required, the collector must consult with the relevant NPWS Office prior to collection and obtain a written variation to the licence or certificate. · NPWS may prohibit, condition or limit collecting for some species at some sites if the collecting would affect research plots. Other conditions or prohibitions may apply after consideration of population estimates, age structure and viability. Where any doubt exists as to the advisability of permitting the collection or the level of collection to be permitted, a precautionary approach shall be enforced.
NSW National Parks and Wildlife Service 19 43 Bridge Street Hurstville 2220 (02) 9585 6444