Threatened species & ecological communities

National Recovery Plan for the Striped Legless Lizard (Delma impar) 1999-2003

Warwick J. S. Smith & Peter Robertson
NSW National Parks and Wildlife Service & Wildlife Profiles Pty Ltd, June 1999

Contents

Acknowledgments

This Recovery Plan has resulted from the combined efforts of many people who have contributed to the study and research of this species. In particular, the following people and groups are gratefully acknowledged:

Warwick Smith and Peter Robertson prepared the Plan, and included comments on various drafts from Recovery Team members. James Dawson and Chris Banks collated final comments and included these in the final draft.

All members of the National Recovery Team contributed to the contents of this Recovery Plan. Particular thanks to Chris Banks, David Shorthouse, Marjo Rauhala, Phil du Guesclin, Colin Hocking, Will Osborne, Graeme Coulson, Alan Webster, Sue Hadden, James Dawson and Wendy Harding for their input.

Thanks also to the Australian Museum, the Museum of Victoria, the Australian Wildlife Collection (CSIRO), the South Australian Museum, the Atlas of Victorian Wildlife (NRE), and many others who provided records of the species. Karl Bossard of Environment Australia produced the distribution maps.

This report has been prepared in accordance with guidelines and requirements under Commonwealth and State legislation, and is intended to complement regional plans produced in Victoria, the ACT and New South Wales.

Publication reference and availability details:

Smith, W.J.S. & P. Robertson (1999). National Recovery Plan for the Striped Legless Lizard (Delma impar): 1999-2003. Unpublished report to Environment Australia, Canberra.

1. Summary

Current species status

The Striped Legless Lizard, Delma impar, is listed as threatened under the following international, commonwealth, state and territory legislation and documentation: IUCN (1996); ANZECC (1991, 1995); Schedule 1, Part 2 of the Endangered Species Protection Act 1992 (Commonwealth); Action Plan for Australian Reptiles (Cogger et al. 1993); Section 21 of the Nature Conservation Act 1980 (ACT); Schedule 6 of the Nature Conservation Act 1980 (ACT); Schedule 2 of the Threatened Species Conservation Act 1995 (NSW); and Schedule 2 of the Flora and Fauna Guarantee Act 1988 (Vic.).

Habitat requirements and limiting factors

Delma impar is a grassland specialist, being found only in areas of native grassland and nearby grassy woodland and exotic pasture. Natural temperate grassland is one of Australia's most threatened ecological communities. It is the loss and degradation of native grassland, through a variety of processes, that is primarily responsible for the decline of D. impar.

Primary objective

The primary conservation goal is to ensure the long-term survival of D. impar and maintain its potential for evolutionary development in the wild across its natural geographic range.

Implicit is maintaining the species' ability to survive, flourish and maintain its potential for evolutionary development in the wild and throughout its natural geographic range. While down-listing of threatened status may be achieved in one or more jurisdictions, the nature of the known threats to the survival of D. impar are such that this may not be realistic across the species' entire range.

Primary recovery criterion

Viable populations or clusters of populations of D. impar are represented and maintained in reserves or appropriately managed sites across the known distribution of the species.

Specific objectives

  1. Establish and maintain national forums for the discussion and organisation of the conservation of D. impar across its natural distribution.
  2. Determine the distribution of potential D. impar habitat.
  3. Determine the current distribution and abundance of D. impar in Victoria, New South Wales, the Australian Capital Territory and South Australia.
  4. Establish a series of reserves and other managed areas such that viable populations are maintained across the known distribution of the species.
  5. Determine the habitat use and ecological requirements of D. impar.
  6. Identify the nature and extent of the threatening processes affecting D. impar.
  7. Undertake a program of research and monitoring to provide a basis for adaptive management of D. impar.
  8. Increase community awareness and involve the community in aspects of the recovery program.
  9. Assess the need for salvage and translocation, determine their feasibilities, develop protocols and undertake a trial translocation if appropriate.
  10. Ensure that captive population(s) are used to support education and research elements of the Recovery Plan.

Specific performance criteria

These criteria, 1 to 10, directly address objectives 1 to 10 above:

  1. All agencies, institutions, community groups and individuals which have an interest in the conservation of D. impar and its grassland habitats have opportunities to be involved in the regional working groups which are represented on the National Recovery Team. The working groups and the National Recovery Team continue to coordinate implementation of recovery and action plans, coordinate projects, organize workshops, and disseminate information at the high level which has been achieved to date. In particular, the National Recovery Team will:
    • Establish strategic objectives and research and management priorities for the conservation of the Striped Legless Lizard (SLL) throughout its distribution.
    • Facilitate preparation of the National Recovery Plan and the co-ordination of the National and State/Territory management strategies, oversee their implementation and participate in their review.
    • Monitor and evaluate success of research and management programs.
    • Assist with seeking resources for conservation programs and advise on their effective use.
    • Provide for exchange of information on the conservation of the SLL and provide authoritative advice as required.
    • Foster community awareness of, and involvement in, and the establishment of extension programs for the conservation of the SLL.
    • Integrate SLL research and management with wider grassland conservation efforts (and organisations).
  2. Key habitat requirements are known and are used to establish the extent and use of potential native and non-native habitat.
  3. Improved and more effective techniques for surveying, estimating population sizes and monitoring D. impar populations have been developed. Surveys of D. impar distribution in NSW, Victoria and South Australia have been completed.
  4. Viable populations are under secure management in reserves and other managed areas across the natural distribution of the species. All personnel involved in managing D. impar habitat have been adequately trained in the requirements of the species and in the implementation of actions from this Recovery Plan.
  5. A detailed understanding of the spatial and ecological requirements of D. impar is established and the consequences for management are understood.
  6. The nature and extent of threats to D. impar are well understood and a program for ameliorating the effects of critical threatening processes is established.
  7. A monitoring system which is efficient and causes minimal habitat disturbance is established across the distribution of the species. Results can be related to past survey and monitoring efforts. Optimum management of D. impar habitat has been determined and is being implemented with regard to fire, grazing, predators and conservation of other site attributes.
  8. Community is aware of, and involved in, recovery actions and management of D. impar. Landowners participate in off-reserve management.
  9. The need for salvage of individuals from doomed sites has been assessed and protocols developed. The need for translocation for both re-establishment of populations and for genetic exchange between populations has been examined and, if necessary, protocols developed and a trial(s) conducted.
  10. The roles of captive populations of D. impar have been defined and goals set. Animals are utilised in research programs. Public display established. Large outdoor enclosures established to simulate natural environmental conditions.

Specific actions

These actions, 1 to 10, directly address objectives 1 to 10 and performance criteria 1 to 10 above.

The figures in brackets indicate the numbering as in section 3 of the Recovery Plan.

  1. Maintain the National Recovery Team and regional working groups (3.1.1).
    • Review performance of Recovery Plan annually (3.1.2).
    • Establish coordinated databases for each State or Territory agency (3.1.3).
    • Encourage tertiary institutions to participate in a coordinated research effort for D. impar (3.1.4).
  2. Determine whether D. impar can persist in the long-term in exotic grassland isolated from native grasslands (3.2.1).
    • Undertake research to determine the relationship between the structure and floristics of grasslands and the abundance of D. impar (3.2.2).
    • Conduct vegetation surveys of grasslands (including soil types), particularly in New South Wales, to determine the extent of potential habitat for D. impar (3.2.3).
  3. Develop an improved detection technique (3.3.1).
    • Develop an improved marking technique (3.3.2).
    • Complete D. impar surveys within potential habitat in Victoria (3.3.3).
    • Commence surveys of potential habitat within NSW; survey the extent of the known populations (3.3.4).
    • Complete surveys of potential habitat in the ACT (3.3.5).
    • Survey remaining potential habitat in south-eastern South Australia (3.3.6).
  4. Undertake Population and Habitat Viability Assessments (3.4.1).
    • Undertake genetic studies of D. impar populations across the range of the species (3.4.2).
    • Develop a national system of managed sites which will ensure the survival of the species across its geographic range (3.4.3).
    • Formulate interim management guidelines for management of D. impar habitat. Implement interim management within reserve areas and, where possible, in other areas of habitat identified as most important in the cluster strategy (3.4.4).
    • Investigate the balanced management of grassland habitats, recognizing the potential for conflicting management requirements of other conservation values (3.4.5).
    • Investigate the need for active translocation between isolated populations to avoid inbreeding (3.4.6).
    • Provide training for personnel involved in activities which may affect D. impar and its habitat (3.4.7).
  5. Develop an effective method for tracking D. impar (3.5.1).
    • Determine the life history of D. impar (3.5.2).
    • Undertake studies of the demography of D. impar (3.5.3).
    • Determine the daily and seasonal habitat use of D. impar (3.5.4).
    • Undertake studies into the diet of D. impar and food availability in different grassland types (3.5.5).
  6. Identify threats to the habitat at known sites and determine the relative severity of these threats (3.6.1).
    • Undertake research on the impact of predators on D. impar (3.6.2).
    • Undertake research on the effects of fire and grazing on the demography of D. impar, particularly with respect to grassland types and season (3.6.3).
  7. Implement a minimum disturbance monitoring strategy at a representative series of sites (3.7.1).
    • Establish appropriate management strategies for sites supporting D. impar (3.7.2).
  8. Provide opportunities for interested community groups and individuals to participate in
    recovery actions (3.8.1).
    • Produce interpretative materials on grasslands and D. impar conservation and management for use with school and community groups, landholders, and private and government organisations (3.8.2).
    • Liaise with grassland managers and develop management guidelines for landholders responsible for off-reserve land which supports D. impar (3.8.3).
    • Seek sponsorship for community involvement in projects directed to the conservation of D. impar and native grasslands, and, where possible, provide support to community groups undertaking approved projects (3.8.4).
  9. Obtain agreement on circumstances under which D. impar may be salvaged from doomed sites, and develop agreed protocols for each State and Territory (3.9.1).
    • Determine the feasibility and appropriateness of translocation (3.9.2).
    • If translocation is appropriate, develop an agreed protocol (3.9.3).
    • Undertake a trial translocation using the agreed protocol (3.9.4)
  10. Use captive animals to heighten community understanding of the conservation of D. impar and its grassland habitat (3.10.1).
    • Use captive populations to conduct biological studies (3.10.2).
    • Undertake research leading to successful captive breeding (3.10.3).
    • Provide interim housing for any translocated animals if required (3.10.4).

Biodiversity benefits

The conservation of D. impar and its habitat will assist in the conservation of natural temperate grassland, which is one of Australia's most threatened ecological communities. Many other threatened flora and fauna species associated with natural temperate grasslands will benefit greatly from the protection and management of D. impar native habitat.

Estimated cost of recovery

The costs of implementing this Recovery Plan, based on 1999 estimates ($000s/year)

Estimated cost of Recovery

2. Species information

2.1 Description and taxonomy

Delma impar (Fischer 1882), the Striped Legless Lizard, is a member of the family Pygopodidae, the legless or flap-footed lizards (Cogger 1992). As with other members of the legless lizard family, D. impar lacks forelimbs and has only very reduced vestigial hind limbs. These hind limbs are apparent only as small flaps on either side of the vent. Delma impar has a long, thin body. The tail, when unbroken, is about twice the length of the body. The Striped Legless Lizard reaches a maximum total length of about 300 mm, with a maximum snout-vent length (SVL) of about 120mm and a weight of about 8 g. While it shows considerable variation in colour and pattern, D. impar is usually pale grey-brown above and cream on the ventral surface, with a series of lateral and dorso-lateral stripes along the length of the body, becoming diagonal bands on the tail (Wilson & Knowles 1988, Cogger 1992). However, in some individuals, particularly juveniles, these stripes may be very faint or absent. The head is generally darker than the body, tending to black in juveniles. A pale to bright yellow patch is present from the tympanum to the posterior infralabial scales (Coulson 1990).

Superficially, these animals resemble snakes, but can be readily distinguished from the latter by the presence of external ear openings, a fleshy undivided tongue and a tail which, when unbroken, is longer than the body. These are characters not exhibited by snakes (Cogger 1992). Delma impar can be readily distinguished from other pygopodids by body colouration, body size and head scalation. The species which most closely resembles D. impar, and which overlaps in distribution, is the Olive Legless Lizard, Delma inornata. The published morphological difference between these taxa is the fusion or partial fusion of the nasal and first supra-labial scale in D. impar, and the clear separation of these scales in D. inornata (Kluge 1974, Cogger 1992). However, this character has been found to be inconsistent, with some specimens of D. impar having clearly separated nasal and first supra-labial scales (Jenkins & Bartell 1980, Coulson 1990). Despite these difficulties, experienced workers can readily identify specimens of either species.

The sexes of D. impar appear very similar externally. However, adult males may be distinguished by the presence of a small rounded 'spur' under each hind limb flap (pers. obs., Rauhala 1998)

2.2 Taxonomic significance

Delma impar is a well-defined species within a well-defined genus containing 17 species (Cogger 1992). It is unique in being the only pygopodid which is a southern grassland specialist. While other legless lizards occur in temperate grasslands, they are not restricted to them.

2.3 Distribution

2.3.1 Geographical distribution

Delma impar is patchily distributed in grasslands of south-eastern NSW, the ACT, north-eastern, central and south-western Victoria, and, possibly, south-eastern South Australia. It is believed to have declined throughout its distribution and is known to have disappeared from many sites.

The distribution of D. impar is shown on Map 1, overlain on IBRA biogeographic regions (Thackway and Cresswell 1995). Proposed 'cluster' boundaries, as formulated during the population and habitat viability workshop (ARAZPA 1996), and explained briefly in Appendix B, are also shown on this map. The predicted distribution of D. impar according to BIOCLIM (Busby 1991) is shown on Map 2. (The maps fold out at the end of this plan).

2.3.2 Tenure of land supporting D. impar

Delma impar is currently known from only three conservation reserves across its entire distribution; the Derrimut Grasslands Reserve in southern Victoria, the Gungahlin Grasslands Reserve in the north of the ACT, and the newly-acquired, as Kuma Nature Reserve near Cooma in NSW. Of the seven sites currently known to support the species in NSW, two are on private land, one on private rural-residential land, one on council-owned land, two on land managed by the Rural Lands Protection Board (RLPB), and one on land owned by the NSW NPWS. The sites in Victoria outside Derrimut Grasslands Reserve are on a variety of government and private land, including many rural properties. The sites outside the Gungahlin Reserve in the ACT are on a mix of private leasehold, military, ACT government and Commonwealth government land.

2.4 Life history

The life history of D. impar is largely unknown. All information that has been gathered is from Victoria and the ACT.

Adult individuals have been recaptured in the wild almost seven years after first capture (Rauhala 1997). Adults have also been held in captivity for seven years (C. Banks pers. comm.). Estimates of lifespan by researchers (ARAZPA 1996) start at about 10 years, but individuals may live significantly longer. Age at first reproduction is thought to be 2-3 years for males and 3-4 years for females (ARAZPA 1996). However, this is based only on estimates of growth rates and expected life history patterns. Each female lays two eggs and it is believed most adult females are capable of breeding every year. Eggs are laid in December/January and hatch in January/February. Hatchlings measure about 40-45mm snout-vent length and weigh about 0.5-0.75g (Banks & Hawkes in prep.). During November and December, adults are more active than at any other time of the year. This activity is thought to be related to mating and egg laying requiring increased movements of both sexes.

Very little is known about the movements and micro-habitat use of D. impar, although some information has been gained from recapture data and from fluoro-dye tracking (Kutt 1993, Kukolic et al. 1994, Rauhala 1996). Animals have been recorded moving at least 20m in one day (Kutt 1993), and up to 50m over several weeks (K. Kukolic pers. comm.). This implies that these animals may be relatively wide-ranging, supporting the belief that they are active hunters, at least some of the time (Nunan 1995). Most of the movement records, apart from those reported by Kutt (1993), have been recorded during the November/December high activity period, and may be due to reproductive activity rather than normal home range movements.

Studies of the diet of D. impar indicate that the species feeds primarily on spiders, crickets, Lepidopteran larvae and cockroaches (Coulson 1990, Wainer 1992, Nunan 1995). Despite their availability, Isopoda (slaters), Hemiptera (true bugs) and Formicidae (ants) were not found to be part of the diet of D. impar, indicating some degree of specialisation (Nunan 1995). However, these relatively unpalatable arthropods are often avoided by reptiles (Greer 1989). Prey availability was not found to be a limiting factor in terms of the distribution of D. impar in native or non-native grasslands in the ACT (Nunan 1995). The diet of these lizards suggests that they are active foragers, although they may also catch prey using a sit-and-wait ambush style of feeding (Nunan 1995).

It is assumed that D. impar shelters mainly in grass tussocks and other thick ground cover. They are also known to utilise soil cracks in Victoria, shelter beneath rocks at numerous sites in Victoria and near Cooma in NSW, and one individual has been found in a spider burrow in the ACT. Other ground debris such as timber and asphalt is occasionally utilised (Coulson 1990, J. Dorrough pers. comm., Kukolic et al. 1994, M. Rauhala 1996).

Delma impar enters a state of torpor for the winter months, although the exact timing of this and the torpor sites are mostly unknown. It has been found that animals in Victoria overwinter mostly in soil cracks, under/beside rocks and in tussock bases. In the ACT, however, most sites have little or no rock cover or soil cracking, and it is therefore assumed that grass tussocks provide the primary overwinter refuges. Individuals have been found underground in cracks formed beside pitfall traps in the ACT, indicating that D. impar will shelter beneath the surface where opportunity allows. They have also been found in burrows in the ACT (M. Rauhala pers. comm.). Many of the sites where D. impar are found have poor drainage and are often waterlogged during the winter (pers. obs.). This would presumably prevent the use of subterranean overwintering sites, and again points to grass tussock bases as the most likely alternative.

2.5 Habitat

Until recently, D. impar was thought to inhabit only native grasslands dominated by species such as Stipa bigeniculata (Spear Grass) and Themeda triandra (Kangaroo Grass). In recent years, surveys have revealed D. impar in many sites dominated by exotic grasses such as Phalaris aquatica, Nasella trichotoma and Hypocharis radicata (Corrigan et al. 1996, O'Shea 1996, Kukolic et al. 1994, Rauhala et al. 1995, Rauhala 1996, Hadden 1995, Coulson 1990). They have also been found in several secondary grassland sites (i.e. sites which were not historically grassland, but which have been cleared for grazing or agriculture). The presence of a relatively dense and continuous structure, rather than the floristic composition of the grasslands, may be important in influencing the persistence of D. impar.

It appears that while D. impar are restricted to grasslands and may occur in woodland, they are not restricted to native or primary grassland. The key to their survival in rural areas may be the availability of shelter during disturbance events (such as heavy grazing or perhaps even ploughing), from which they may be able to recolonise disturbed sites after the cessation of the disturbance (Dorrough 1995). This shelter may take the form of plant species which are relatively unpalatable to stock, such as Serrated Tussock or Juncus sp., road easements, less disturbed neighbouring land or even soil cracks and arthropod burrows in the short-term. It is not known if grassland dominated by introduced species can support D. impar populations in the long-term, but there is evidence that they do reproduce in these habitats (Rauhala et al. 1995, Corrigan et al. 1996).

2.6 Current ex situ programs

At the time of writing (June, 1999) there are two captive groups of D. impar. One is at the Melbourne Zoo in Victoria, and the other is held at Tidbinbilla Nature Reserve in the ACT by Environment ACT. Both of these groups originated mostly from salvage operations performed prior to destruction of grassland sites for development. A third captive colony is proposed for the Animal House at VUT (Werribee), based on animals salvaged from the Albion grasslands (C. Hocking, pers. comm.).

Captive breeding of D. impar has been achieved at Melbourne Zoo in 1998, with three young being successfully raised from eggs resulting from captive matings (Banks & Hawkes, in prep.). Additional eggs laid in captivity by wild-caught gravid females have been hatched and the juveniles raised (Kukolic et al. 1994, C. Banks, M. Rauhala, H. Osmond pers. comm.).

2.7 Management issues

2.7.1 Threats

The main threat to D. impar across its entire range is habitat degradation and destruction. Approximately 99.5% of natural temperate grassland has been destroyed or drastically altered since the event of European settlement (Kirkpatrick et al. 1995). While D. impar may persist for some time in modified grasslands, it can be eliminated from an area by extended intense grazing, pasture improvement, ploughing, drought or other heavy disturbance. Such areas may be recolonised by the species, but this is probably dependent on the availability of nearby undisturbed refuge areas.

Fire has been recorded as causing mortality in the species (Coulson 1995, Walton 1995), but the extent to which populations are affected is unknown. Extensive fires over large areas are thought to cause direct mortality, as well as reducing cover for the species and its prey and exposing animals to increased predation. The behavioural reaction of D. impar to fire is unknown, although it seems likely that survivors would either move into unburnt areas or remain relatively inactive in the soil or under rocks until the vegetation recovers enough to provide shelter.

Predation as a threatening process is as yet unmeasured. It is assumed that a range of native predators including snakes, other lizards, raptors, magpies and other predatory birds, and possibly Dunnarts, will prey on D. impar, but the extent of this predation and its effect on populations is unknown. There has been speculation about the potential for an increase in raptor presence and thereby impact on D. impar resulting from the provision of perching sites such as telegraph poles in grasslands. Introduced predators may be more of a concern, as urban development surrounds many D. impar populations. There is some anecdotal evidence which suggests that foxes may prey upon D. impar (e.g. S. Walton pers. comm.), and domestic cats could have a large impact on local populations where suburban housing abuts grasslands. However, because D. impar are extremely cryptic and secretive animals, predation may not be a significant threat. This requires further investigation. There is some evidence from scats that foxes travel along pitfall trap lines and may in fact be feeding from the pits. This is yet to be demonstrated but, if it is occurring, it could have a significant impact on both the populations of D. impar and their study.

2.8 Social and economic consequences of the Recovery Plan

2.8.1 Economic considerations

There is a variety of conservation-based actions which may be appropriate and necessary in different land tenure situations. These actions have economic implications for both private individuals and various government organisations/agencies. These are summarised in Table 1.

Table 1. Recovery actions which will have economic impacts, and those parties which will be affected.
Action Affected parties
Altered stocking rates. Rural landowners/lessees.
Restriction on management practices, e.g. pasture improvement, controlled burning and slashing. All managers of land with D.  impar populations.
Land acquisition.

State/Territory and Commonwealth conservation agencies.

Rural landowners.
Rejection of, or alteration to, proposed developments.

Developers.

Land owners.

Any parties serviced by the proposed development.

Government or corporations, such as Telstra and RTA.

2.8.2 Social considerations

There are both positive and negative social consequences of implementing this Recovery Plan. The major positive consequence is fulfilment of a community expectation for maintenance of biodiversity, and the long-term protection of both D. impar and grassland habitat for the enjoyment of present and future Australians.

Because much of the remaining D. impar habitat is on privately owned land, the opportunity exists for landholders to make substantial contributions towards the conservation of this species. It will be important to develop management agreements with landholders which attempt to integrate conservation management practices with everyday rural land management, and to maintain a harmonious relationship between the various land managers responsible for D. impar populations.

The alteration or rejection of development proposals on land containing D. impar populations can have adverse social impacts. Where services are to be supplied by the development, the alteration or denial of these services may have a substantial social impact. The extent of this impact will vary from site to site and will depend upon the type of proposed development.

2.8.3 Practical considerations

Surveys for D. impar are expensive, time-consuming and may produce little useful data. The survey methods currently available for this species are often disruptive of the habitat and may adversely affect other grassland values. Therefore, it may not be practical to survey all known habitat within the time frame of this Recovery Plan. Conservation agencies should therefore use all other means at their disposal for obtaining this information. Many records of this and other threatened species come from non-targeted survey work, such as that undertaken by consultants and students. Conservation agencies should encourage consultants to undertake targeted surveys for D. impar whenever they are working in potential habitat, and a standard methodology should be developed. It is extremely important that these records are incorporated by conservation agencies into their databases. In this way, even without targeted surveys, increasing knowledge of distribution can be obtained.

2.9 Biodiversity benefits

In taking actions to conserve D. impar, there are considerable advantages for many other threatened species and communities. Natural temperate grasslands have been reduced to just 0.5% of their extent at the time of European settlement (Kirkpatrick et al. 1995). The broad habitat of D. impar is natural temperate grassland. Consequently, the conservation of D. impar involves conservation of such grassland areas and the suite of threatened species associated with them. Delma impar has in many instances acted as a 'flagship' species in the conservation of natural temperate grasslands, because extensive promotional activities have been able to attract considerable attention based upon the 'novelty' and 'public appeal' of the species. The promotion of grassland conservation, however, is problematic because grasslands do not have the broad public appreciation of forests, rivers or wetlands. Because of this, having a species such as D. impar as a well-known and well-liked 'flagship' can be invaluable in the overall conservation of natural temperate grasslands.

2.10 Previous actions undertaken

2.10.1 Coordination and communication of research and recovery actions

An Action Statement for D. impar has been prepared in Victoria (Webster et al. 1992), in accordance with the Flora and Fauna Guarantee Act 1988. This Action Statement documents the range of actions previously undertaken and lists actions required for the conservation of the species in that State. It is now due for review.

An Action Plan for D. impar in the ACT was finalised and adopted in 1997 (ACT Government 1997a), in accordance with section 23 of the Nature Conservation Act 1980.

A draft recovery plan for D. impar has been prepared in NSW and is soon to be released for public comment.

A National Recovery Team (NRT or SLLNRT) for D. impar was established in December 1995. This team has been coordinating national survey and research efforts since its establishment. Survey and research directions are planned and acted upon primarily by two regional working groups: the Victorian Striped Legless Lizard Working Group (VSLLWG), and the ACT and NSW Striped Legless Lizard Regional Working Group (SLLRWG). The VSLLWG was established in December 1990, and is the body recommended in the Action Statement to coordinate management actions in Victoria (Banks 1992, Kutt et al. 1995, Webster et al. 1992). These two regional working groups deal with the specific issues faced by their regions and report back to the NRT regarding progress on recovery actions. Regional and national groups are in constant communication with other relevant working groups and recovery teams, such as the Grassland Earless Dragon National Recovery Team and various grassland recovery groups. The work coordinated by the working groups has provided most of the current knowledge of D. impar distribution and biology.

Organisations represented on the three groups are as follows:

Striped Legless Lizard National Recovery Team (SLLNRT or NRT)

ACT and NSW Striped Legless Lizard Regional Working Group

Victorian Striped Legless Lizard Working Group (VSLLWG)

*advisory and observer role

The terms of reference of the Striped Legless Lizard National Recovery Team are:

2.10.2 Population and habitat viability analysis

A Population and Habitat Viability Analysis (PHVA) workshop was conducted in Canberra in July-August 1996 by the Conservation Breeding Specialist Group of the IUCN's Species Survival Commission, in collaboration with the National Recovery Team, the Australasian Regional Association of Zoological Parks and Aquaria Inc. (ARAZPA), and the ACT Parks & Conservation Service (ARAZPA 1996). Most members of the Recovery Team, as well as other interested groups and individuals, participated in this exercise. This workshop provided insight into the factors which are important in the population dynamics of D. impar and this information will be used to direct research and conservation efforts.

2.10.3 Surveys

Extensive survey programs have been conducted in both the ACT and Victoria. In the ACT there are no extensive areas of potential habitat remaining which have not been surveyed. In Victoria survey efforts have concentrated in the Melbourne region and some areas in the west of the State, but even there are not complete. Some broad surveys have been conducted within the range of D. impar in South Australia, but have not located the species (J. Foulkes, DEHAA, pers. comm.).

Few targeted surveys have been undertaken in NSW, the most recent successfully locating the species near Goulburn (J. Dawson pers. comm.). Recent surveys by ecological consultants have found D. impar at two sites in the Monaro region (Dorrough et al. 1996, Frankenberg & Frankenberg 1998). As the distribution of D. impar is poorly understood in NSW, extensive targeted reptile surveys are planned for areas of potential habitat, including the Yass region in 1999. Further vegetation surveys are planned in order to identify new areas of potential habitat for later targeted surveys.

2.10.4 Research

Research into various aspects of the biology of D. impar has been instigated and is continuing. Habitat relationships have been the focus of much attention, to attempt to identify management requirements (Dorrough 1995, Hadden 1995, O'Shea 1996, O'Shea & Hocking 1997), and the effects of fire (Walton 1995). Movements have been examined (Kutt 1993), and the diet has been determined (Wainer 1992, Nunan 1995). Recent studies have investigated alternative trapping or detection techniques for the species (Nielsen & Underwood 1997, O'Shea & Hocking undated) with little success to date. Basic demographic parameters, such as mortality, recruitment, growth and life-span remain largely unknown, as do the effects of various habitat disturbance factors (e.g. fire, grazing and weed invasion).

2.10.5 Reservation

Delma impar is present in three reserves, one in Victoria, one in the ACT and one in NSW. The Victorian reserve (Derrimut Grassland Reserve) is approximately 150 ha, and the ACT reserve (Gungahlin Grassland Reserve) is actually three separate, but abutting areas with a total of about 500 ha. The NSW reserve (Kuma Nature Reserve) near Cooma is 180 ha. Three additional grassland reserves have been proposed by the Victorian Government - the Terrick-Terrick National Park north of Bendigo, the Craigieburn Grasslands Flora & Fauna Reserve north of Melbourne, and the Cressy Grasslands Flora & Fauna Reserve west of Geelong (Victorian Government, 1996). Delivery of these commitments will significantly enhance the conservation of D. impar.

Similarly, the planned addition to the reserve system of Commonwealth land at Albion in Victoria is an extremely important conservation measure. ACT Action Plans Nos. 1 and 2 give details of current proposed reservation and agreement strategies for the ACT grasslands (ACT Government 1997). These few reserves, existing and proposed, provide the start of a core of essential areas for the conservation of D. impar, as will be identified by the 'cluster' planning approach detailed in Appendix B.

2.11 Species ability to recover

There is circumstantial evidence to suggest that D. impar may recover after certain short-term disturbances, for example grazing, fire and drought (Dorrough 1995, Rauhala et al.1995, Rauhala 1996, Kukolic 1994), but the frequency and duration of these threats are undoubtedly important in determining recovery. It is as yet unknown whether the species will persist in the long-term in reserved areas, or what active management will be required. Again, this will depend on the size of the reserves and on the threats present. The effect of introduced predators is not well understood, and may be significantly detrimental in grasslands adjacent to urban areas (such as the Gungahlin Grassland Reserve). When population sizes are reduced by catastrophes, the ability of the species to recover will be limited by its low fecundity.

When appropriate reservation and conservation management has been determined and implemented, it should be possible for conservation of the species to be secured.

2.12 Alternative management strategies

Management agreements with, and sympathetic land use by, non-government landholders will play a crucial role in the conservation of D. impar. It is clear that not all rural land uses have significant detrimental effects on D. impar populations, and that populations can persist in the long-term on rural land. Consequently, reserves are not the only solution to conserving the species, and should be viewed as only part of the management strategy for this species (see Appendix B - population cluster approach to D. impar management). ACT Action Plans Nos. 1 and 2 give details of current proposed reservation and agreement strategies for the ACT grasslands (ACT Government 1997a & b). A Public Authority Management Agreement has been established to conserve one area of D. impar habitat in central Victoria (P. Johnson, pers. comm.). Similar agreements may be appropriate for Travelling Stock Reserves in NSW.

2.13 Community involvement

There is great potential for community involvement in the conservation of D. impar and natural temperate grasslands, including the population cluster approach referred to above. For example, active support for and involvement in field studies by a farming family in western Victoria has provided valuable information about the species. Because many of the remaining patches of natural temperate grasslands are on private land or in close proximity to suburban areas, the involvement of the community will be critical to the successful recovery of both D. impar and its grassland habitat. There are already several community groups who have made great contributions to both grassland and D. impar conservation. In the ACT, the Friends of Grasslands community group is dedicated to the conservation and recovery of native grasslands and their associated fauna. The Friends of the Striped Legless Lizard is a Victorian community group which has been involved in several conservation-oriented programs, including salvage operations. These groups will be instrumental in the implementation of this Recovery Plan and will be included in many actions. Organising more groups like these, particularly in New South Wales, will be a high priority as the Recovery Plan is implemented.

2.14 Critical gaps in knowledge

Research to date has facilitated the identification of the broad distribution and habitat use of D. impar, and has provided some insights into the basic biology of the species. However, a better understanding of some important areas is required to enable informed management guidelines for the species and its habitat to be formulated. Further research is required into:

3. Recovery plan objectives, criteria and actions

Primary objective

The primary conservation goal is to ensure the long-term survival of D. impar throughout its distribution.

Implicit in this goal is maintaining the species' ability to survive, flourish and maintain its potential for evolutionary development in the wild and throughout its natural geographic range. While down-listing of threatened status may be achieved in one or more jurisdictions, the nature of the known threats to the survival of D. impar are such that this may not be realistic throughout its distribution.

This primary objective is broken down into ten specific conservation objectives aimed at focusing resources on achieving the primary objective.

Each of the actions required to achieve the 10 objectives has been allocated one of three priorities, with #1 being the highest priority and #3 the lowest.

Primary recovery criterion

Viable populations or clusters of populations of D. impar are represented and maintained in reserves or appropriately managed sites across the known distribution of the species.

3.1 Specific conservation objective 1

Establish and maintain national forums for the discussion and organisation of the conservation of D. impar across its natural distribution.

Performance criteria

All agencies, institutions, community groups and individuals which have an interest in the conservation of D. impar and its grassland habitats have opportunities to be involved in the regional working groups which are represented on the National Recovery Team (NRT).

The working groups and the National Recovery Team continue to coordinate implementation of recovery and action plans, coordinate projects, organize workshops, and disseminate information at the high level which has been achieved to date. In particular, the NRT will:

Establish strategic objectives and research and management priorities for the conservation of the SLL throughout its distribution.

Facilitate preparation of the National Recovery Plan and the co-ordination of the National and State/Territory management strategies, oversee their implementation, and participate in their review.

Actions required to achieve objective

3.1.1 Maintain the National Recovery Team and regional working groups

The National Recovery Team and regional working groups have been instrumental in the organising of work completed to date and in disseminating information. This high level of organisation and communication must continue if this Recovery Plan is to be implemented successfully. Landowner participation in the recovery process is to be encouraged, and supported if possible.

3.1.2 Review performance of Recovery Plan annually
3.1.3 Establish coordinated databases for each State or Territory agency

Some steps were taken toward achieving this aim during the PHVA workshop held in the ACT during August 1996. The Victorian and ACT databases are very comprehensive and reasonably compatible. There is very little data for NSW or South Australia, but as this is collected it must be done so in a way which is compatible with the existing ACT and Victorian data.

3.1.4 Encourage tertiary institutions to participate in a coordinated research effort for D. impar

The contributions made to D. impar conservation and research to date by tertiary institutions have been significant. There are several institutions which have shown a continuing interest in this field and these are encouraged and assisted by the working groups and National Recovery Team. These associations will continue and student research should continue to provide valuable contributions to the recovery of the species.

3.2 Specific conservation objective 2

Determine the distribution of potential D. impar habitat.

Performance criterion

Key habitat requirements are known and are used to establish the extent and use of potential native and non-native habitat.

Actions required to achieve objective

3.2.1 Determine whether D. impar can persist in the long-term in exotic grassland isolated from native grasslands

It is important to determine the extent of potential habitat for D. impar. It is known that D. impar is found in exotic grasslands, but it is still unclear whether these sites act only as temporary refuges, populations sinks, or are actually capable of sustaining populations. In the ACT, breeding populations of D. impar have been found in two exotic-dominated sites which had been isolated from other areas of grassland for over eight years (Corrigan et al. 1996, Kukolic et al. 1994). Unfortunately, one of these sites has since been destroyed and can provide no further information. The other site (Kaleen) should be monitored to determine the viability of the population. Similar sites in Victoria, such as the Albion Explosives Factory site, must also be monitored.

3.2.2 Undertake research to determine the relationship between the structure and floristics of grasslands and the abundance of D. impar

Focus on existing known populations of D. impar to determine what local vegetation characteristics affect abundance within sites.

3.2.3 Conduct vegetation surveys of grasslands, particularly in New South Wales, todetermine the extent of potential habitat for D. impar

Once the key habitat requirements of the species have been determined, this information must be used to conduct vegetation surveys with the aim of targeting areas for D. impar survey.

3.3 Specific conservation objective 3

Determine the current distribution and abundance of D. impar in Victoria, New South Wales, the Australian Capital Territory and South Australia.

Performance criteria

Actions required to achieve objective

3.3.1 Develop an improved detection technique

The current trapping technique is very labour intensive to install, may not be as effective and reliable as desired and causes significant disturbance to the grasslands in which it is used. Development of an improved technique which is less labour intensive, more effective and causes less habitat disturbance is a high priority. Preliminary investigations (Nielsen & Underwood 1997, O'Shea & Hocking 1998) have not yet provided a viable alternative to current methods.

3.3.2 Develop an improved marking technique

Research into the reliability of the current animal marking technique (heat branding) and an assessment of alternatives are required. Freeze branding is has been trialed by EACT on captive animals at Tidbinbilla Nature Reserve without success. The use of PIT tags will also be investigated.

3.3.3 Complete D. impar surveys within potential habitat in Victoria

Extensive surveys have already been conducted in the Melbourne region and the basalt plains to the west of Melbourne. These are still far from comprehensive and must be completed. Very little survey work has been conducted in central northern Victoria, the Wimmera and eastern Victoria, and more is still required. Sites which historically contained D. impar should be revisited in order to determine whether or not the species is still present.

3.3.4 Commence surveys of potential habitat within NSW and survey the extent of theknown populations

At this time, all of the known populations in NSW have been found during general survey and consultancy work. There have been few specific targeted surveys for D. impar in NSW aimed at establishing either the distribution or abundance of this species in the state, although an extensive targeted survey of the Yass region in 1999 will begin to address this lack of information. This work will enable a national perspective on the conservation of D. impar. Sites which historically supported D. impar should be revisited in order to determine if the species is still present.

3.3.5 Complete surveys of potential habitat in the ACT

This work has largely been completed by the Wildlife Research & Monitoring Unit of Environment ACT. It is believed that there are no significant areas of potential D. impar habitat remaining in the ACT which have not been surveyed.

3.3.6 Survey remaining potential habitat in south-eastern South Australia

A brief survey was conducted at the Bool Lagoon site in South Australia in 1995 (J. Foulkes, DEHAA, pers. comm.) but no D. impar were located. This was repeated in June 1998 by a member of the VSLLWG, for DEHAA, but no D. impar were found and the habitat appeared unsuitable for D. impar (Y. Ingeme, NRE, pers. comm.). It is likely that there is further potential habitat in this region, and vegetation assessments should be undertaken to direct survey work to determine the western extremity of the species distribution. Other grassland areas in south-eastern South Australia should be investigated.

3.4 Specific conservation objective 4

Establish a series of reserves and other managed areas such that viable populations are maintained across the known distribution of the species.

This is the most critical of the actions outlined in this Recovery Plan. Due to the nature of the threats to D. impar, the best way to conserve the species is to permanently protect its habitat and to manage these protected sites appropriately.

Performance criteria

Actions required to achieve objective

3.4.1 Undertake Population and Habitat Viability Assessments

A Population and Habitat Viability Assessment (PHVA) has been conducted as a combined exercise between the ACT Parks & Conservation Service, the Striped Legless Lizard National Recovery Team, the Australasian Regional Association of Zoological Parks and Aquaria Inc. (ARAZPA) and the Conservation Breeding Specialist Group (Species Survival Commission of IUCN) (ARAZPA 1996). While components of this PHVA focussed on the newly established Gungahlin Grassland Reserve in the ACT, the methodology can be applied to other populations throughout the species distribution, as population size, mortality and other biological information is determined for the species and for each site. There is insufficient information on demographics, behaviour and life history for these analyses to be very reliable at this time. As this information accumulates, further PHVA analyses will become more useful in directing management decisions.

3.4.2 Undertake genetic studies of D. impar populations across the range of the species

Detailed population genetics studies are important in identifying unique populations and assisting with the determination of conservation clusters (see Appendix B). A study of ACT and Victorian animals has been conducted using allozyme electrophoresis, which found low levels of allozyme variation even between the States for the systems examined (Osmond 1994). In order to obtain results of use to management, more detailed research is required (see also 3.4.5). Tissues will be collected opportunistically during other survey/research projects.

3.4.3 Develop a national system of managed sites which will ensure the survival of the species across its geographic range

A national strategy for a system of managed sites is being developed by members of the National Recovery Team. This system focuses on the concept of ecologically or geographically distinct clusters of populations being permanently protected (either within reserves or by secure long-term management agreements). Further research is required before the cluster approach is fully developed and all units are identified and accepted, but preliminary work suggests that about 17 clusters could be required across the range of the species through Victoria, NSW, the ACT and (if an extant population exists) in South Australia. These cluster boundaries are shown on Map 1. Further explanation of the cluster approach is contained in Appendix B.

As part of this system, as already noted, D. impar is present in three designated grassland reserves in Victoria (Derrimut Grassland Reserve), the ACT (Gungahlin Grassland Reserve) and NSW (Kuma Nature Reserve). Managing the species in these sites, as well as the proposed Albion site and the other three proposed grassland reserves in Victoria, will be vital to its long-term survival.

Most of the known sites which contain D. impar in Victoria and NSW are on private rural land. In the majority of cases the landowners have no obligation to manage the land sympathetically for D. impar, and they have the ability to exterminate D. impar populations through land-use practices which are inappropriate for the lizard. Land management agreements must be made with these landowners, or land must be acquired for reserves in order to adequately conserve the species across its current range. This is particularly important in regions where D. impar populations are not included in reserves. Landowners must be informed about D. impar conservation and assured that the presence of D. impar on their properties does not mean that they will lose their land, or incur significant loss in productivity. It is generally true that significant changes in land management practices are not required in areas that contain D. impar, because their very presence indicates at least a base level of appropriate land-use history. It should be noted that some landowners are very supportive of grassland and D. impar conservation. Voluntary Conservation Agreements (NSW), Public Authority Management Agreements (Vic.), Land for Wildlife (Vic.), and Conservation Covenants are other potential formal arrangements whereby cooperative conservation management may be achieved.

Several of the known sites which contain D. impar in the ACT are occupied by Commonwealth Government agencies and presently used for a variety of purposes. Other sites are on rural land or are in the Gunghalin Grassland Reserve. In the ACT, the Action Plans for Natural Temperate Grasslands (No. 1) and Delma impar (No. 2) give details of current proposed protection measures for D. impar (ACT Government 1997a & b). These measures include reservation of the most significant areas, Property Management Agreements for privately leased land and Memoranda of Agreement for land which is owned or occupied by the Commonwealth Government. Memoranda of Understanding between the Commonwealth and ACT Governments will set out conservation objectives for the land and the management practices required to maintain D. impar populations.

3.4.4 Formulate interim management guidelines for management of D. impar habitat. Implement interim management within reserves areas and, where possible, in other areas of habitat identified as most important in the cluster strategy

Information on the habitat requirements of D. impar, and on the optimal management of its habitat (including restoration of degraded habitat), is incomplete and requires substantial research. However, there is now an urgent need to manage areas of D. impar habitat with respect to fire, grazing, mowing, weed control, recreation, pest animals and other threats, such that further deterioration can be minimised (also see 3.6.1 and 3.7.2). Consequently, decisions must be made, based upon best available knowledge, on the interim management of many areas. Management requirements of other coincident conservation values will be considered. Guidelines for the restoration of degraded native grassland areas should also be considered. Interim management guidelines currently recommended by the NRT are included as Appendix C.

3.4.5 Investigate the balanced management of grassland habitats, recognizing the potential for conflicting management requirements of other conservation values

Other conservation values present within important native grassland areas may have conservation management requirements which differ from those of D. impar (e.g. with regard to burning regimes). The importance of these values and the extent to which they may be compromised by optimal D. impar management must be assessed, and the best possible balance of management strategies formulated.

3.4.6 Investigate the need for active translocation between isolated populations to avoid inbreeding

The first stage in determining the need for assisting genetic flow between populations is determining population sizes, mating system, genetic make-up of various populations, animal movements and natural genetic exchange between populations. The next step is to use this information to determine the likelihood of inbreeding having a negative impact on the survival of populations. If it is determined that inbreeding is a problem, then experiments with translocation must be conducted to discover whether or not it is an effective remedy and, if so, what rates of translocation are appropriate for what populations.

3.4.7 Provide training for personnel involved in activities which may affect D. impar and its habitat

All agency field staff and other personnel who are responsible for the management of grassland areas, or who undertake activities which may affect grassland conservation values, will be trained in the understanding and implementation of appropriate grassland management.

3.5 Specific conservation objective 5

Determine the habitat use and ecological requirements of D. impar.

Performance criterion

A detailed understanding of the spatial and ecological requirements of D. impar is established and the consequences for management are understood.

Actions required to achieve objective

3.5.1 Develop an effective method for tracking D. impar

Many questions about habitat use, activity periods and territoriality could be answered if an adequate tracking technique could be established. Thread spool and fluorescent powder tracking has been attempted (Kutt 1993). The Victorian Striped Legless Lizard Working Group unsuccessfully trialed a harmonic radar diode implanted in a D. inornata in 1997 and is continuing to explore this and other systems, including the use of microwave transponders and radioactive isotopes. Tracking of individuals is vital if we are to determine daily and seasonal movement patterns for the species.

3.5.2 Determine the life history of D. impar

Some of this work has already been conducted by EACT, DNRE, Melbourne Zoo and through several student projects. Despite the work already conducted, there are still large gaps in our knowledge of the life history of this species. These gaps include factors such as animal movements, egg deposition sites and age at reproductive maturity. The answering of outstanding questions depends largely on the development of new field techniques. Knowledge of life history will be used in future PHVA analyses, and will enable more informed management decisions to be made.

Long-term recapture of individuals is very rare. This will need to be addressed if many of the life history traits of D. impar are to be determined. It is not known yet whether the lack of recaptures across trapping seasons is an artefact of animal behaviour, inadequacies of the trapping technique or inadequacies of the animal marking technique, or a combination of all of these factors. As outlined above (Section 3.2.1), work is currently underway to improve trapping techniques and this may help in solving this problem. Tracking of individuals may give an indication of why long-term recapture rates are so low and indicate methods for improving techniques.

3.5.3 Undertake studies of the demography of D. impar

Knowledge of factors such as age-related mortality and reproductive life span are vital in understanding and managing this species. When this information is reliably determined, it can be used in PHVA analyses, making them significantly more useful in aiding management decisions. Methods to reliably sex individuals have been developed at MZ and by EACT.

3.5.4 Determine the daily and seasonal habitat use of D. impar

Knowledge of the patterns of seasonal and daily habitat use is important to assist in determining optimal management of the habitat. This information is difficult to obtain and will be largely dependent upon the development of reliable tracking techniques (see action 3.5.1). Continuing observation of, and work on, the captive populations at Melbourne Zoo and Tidbinbilla Nature Reserve will continue to provide useful information on behaviour and life history, as will continued recording of relevant information during survey work.

3.5.5 Undertake studies into diet of D. impar and food availability in different grassland types

Detailed studies of the diet of D. impar in the ACT have been conducted by Nunan (1995) and in Victoria by Coulson (1990) and Wainer (1992) (see also Kutt et al., 1998). Further work may be required in the Monaro region because of the different habitat occupied by the species. However, because the results from the ACT and Victoria are similar, and diet was not predicted to be a limiting factor, extra work on diet in NSW is not a high priority.

3.6 Specific conservation objective 6.

Identify the nature and extent of the threatening processes affecting D. impar.

Performance criterion

The nature and extent of threats to D. impar are well understood and a program for ameliorating the effects of critical threatening processes is established.

Actions required to achieve objective

3.6.1 Identify threats to D. impar and its habitat at known sites and determine the relative severity of these threats

Apart from establishing reserves and managed areas (objective 4), this is probably the most critical action required for the conservation of D. impar. All threats, including development proposals, must be identified and their potential effects assessed. Known threatening processes include:

One avenue for addressing identified threats, and instituting land-use practices which are appropriate for D. impar, is through Local Government Planning schemes.

3.6.2 Undertake research on the impact of predators on D. impar

In order to conduct effective research into the effect of predators on D. impar it will first be necessary to develop an adequate monitoring technique. Current methods are insufficient to accurately detect all but gross changes in population density of D. impar. Acknowledging this situation, there are still some methods which may prove useful. Diet analysis of predators found in grasslands supporting D. impar populations would at least indicate which predators do take D. impar and how often. However, without good monitoring techniques the actual impact of this predation on D. impar populations will be difficult to determine.

3.6.3 Undertake research on the effects of fire and grazing on the demography of D. impar, particularly with respect to grassland types and season

Determining the impact of various management practices on D. impar populations is going to rely once again on the development of an effective monitoring technique. Without this, it will only be possible to detect very dramatic effects. Trials of different burning and grazing regimes need to be conducted on sites supporting known population densities. This may be difficult to achieve and to justify, in which case monitoring sites must be set up in areas with different and/or changing management practices in order to study their effects. Careful consideration of experimental design will be essential for the interpretation of the results of such research.

3.7 Specific conservation objective 7

Undertake a program of monitoring to provide a basis for adaptive management of D. impar.

Performance criteria

A monitoring system which is efficient and causes minimal habitat disturbance is established across the distribution of the species. Results can be related to past survey and monitoring efforts.

Optimum management of D. impar habitat has been determined and is being implemented with regard to fire, grazing, predators and conservation of other site attributes.

Actions required to achieve objective

3.7.1 Implement a minimum disturbance monitoring strategy at a representative series of sites

Some previous attempts to monitor populations of D. impar (e.g. in Derrimut Grassland Reserve) have suffered from extremely low, but variable capture rates and have used inconsistent techniques; they consequently have provided little useful information. An effective, minimum disturbance monitoring technique must be developed which will provide long-term population trend data (see actions 3.3.1 and 3.5.1). Work currently being conducted by members of the National Recovery Team may indicate suitable techniques. In the meantime, sites for monitoring can be selected. Both D. impar and various habitat parameters should be monitored. Sites selected for long-term monitoring should include representatives from all of the site clusters (see Appendix B).

3.7.2 Establish appropriate management strategies for sites supporting D. impar

As the effects of fire, grazing and predators are progressively assessed, detailed and informed management guidelines will be established and updated to ensure the persistence of D. impar populations in all managed areas. Broad management strategies which are known to assist in the recovery of D. impar and its habitat include:

3.8 Specific conservation objective 8

Increase community awareness and involve the community in aspects of the recovery program.

Performance criteria

The community is aware of, and involved in, recovery actions and management of D. impar and its habitat.

Landowners participate in off-reserve management.

Actions required to achieve objective

3.8.1 Provide opportunities for interested community groups and individuals to participate in recovery actions

There are already several community groups and individuals with strong involvement in grassland and D. impar conservation in the ACT and Victoria. Further involvement will be sought from a wider variety of groups within these areas. The establishment of links with similar community groups in NSW is seen as a high priority action and will be pursued as soon as actions are identified in which community involvement would be beneficial.

3.8.2 Produce interpretative materials on grasslands and D. impar conservation and management for use with school and community groups, landholders, and private and government organisations

The production of interpretive material which is easily accessed by land managers, and gives clear summaries of current knowledge of conservation and management of D. impar and its grassland habitat, is essential in promoting sympathetic land management practices outside reserves. These materials will also be important in training conservation agency field staff and keeping all concerned up-to-date on grassland conservation issues. A range of such material has already been produced, including 'A Land of Sweeping Plains', a three volume set of grassland resource books produced by the Zoological Board of Victoria in 1996 (ZBV 1996); roadside signs highlighting important grassland areas; and The members of the regional working groups and National Recovery Team have an excellent exchange of information and all members are kept apprised of recent work.

3.8.3 Liaise with grassland managers and develop management guidelines for landholders responsible for off-reserve land which supports D. impar

All landholders with land supporting D. impar will be contacted by the relevant government conservation agency. Workshops will be held where landholders will be provided with information about D. impar conservation, and where open discussion of the issues relevant to the landholders can lead to appropriate conservation agreements. The exact nature of the implementation of this action will vary from state to state and site to site. Establishment of guidelines for management of native grassland on private properties has been identified as a priority of the Grassy Ecosystems Reference Group and such a field guide was produced by the VNPA in 1998 with funding from the GERG (Lunt et al. 1998). Schemes such as Landcare and Land for Wildlife may be appropriate vehicles for promoting and implementing appropriate conservation management of grasslands (Platt 1998).

Interim guidelines on appropriate management practices for D. impar populations which are not in reserves have been suggested (see Appendix C), but comprehensive guidelines will not be available until research on the long-term effects of fire and grazing on these populations is complete.

3.8.4 Seek sponsorship for community involvement in projects directed to the conservation of D. impar and native grasslands, and where possible provide support to community groups undertaking approved projects

Given the large number and potentially high expense of the actions identified in this Recovery Plan and the relatively low level of government agency funding available for implementing recovery plans, corporate sponsorship may be crucial in achieving the conservation objectives of this Recovery Plan.

3.9 Specific conservation objective 9

Assess the need for salvage and translocation, determine their feasibilities, develop protocols and undertake a trial translocation if appropriate.

Performance criteria

The need for salvage of individuals from doomed sites has been assessed and protocols developed.

The need for translocation for both re-establishment of populations and for genetic exchange between populations has been examined and, if necessary, protocols developed and a trial(s) conducted.

Actions required to achieve objective

3.9.1 Obtain agreement on circumstances under which D. impar may be salvaged from doomed sites, and develop agreed salvage protocols for each State and Territory

Delma impar have been salvaged from a number of doomed sites in Victoria under a protocol agreed by the VSLLWG in 1994, and from one in the ACT, under interim salvage protocols. Salvaged animals in Victoria are housed in a purpose-built captive facility at Melbourne Zoo, where they have been used for various research and education elements of the recovery program to date.

3.9.2 Determine the feasibility and appropriateness of translocation

Translocation of animals for genetic purposes or for reintroduction is a potentially valuable tool in wildlife management. However, it is a complex and long-term undertaking, for which rigorous protocols must be in place, in accordance with international, commonwealth and state and territory guidelines. In the case of D. impar, a clear need must be established before translocation(s) are contemplated. For re-introductions, it will then be necessary firstly to identify sites where D. impar populations were once present but have since disappeared, and secondly to understand the cause of the local extinction, and then eliminate or minimize the threat. Currently, there is a higher priority placed on adequately conserving existing populations than on restoring or creating others.

3.9.3 If translocation is appropriate, develop an agreed protocol

If translocation is considered appropriate, either for genetic reasons or for re-establishing populations, an agreed protocol is required, developed according to current international, commonwealth and state guidelines (see Coulson 1995). The key to this research is the development of effective trapping and tracking techniques (see objective 3.3), without which it will be impossible to monitor translocated animals and determine success or failure of the translocation.

3.9.4 Undertake a trial translocation using the agreed protocol

If translocation is considered desirable for genetic purposes or re-establishment, and once protocols have been established (including site selection), a trial translocation should be undertaken. Monitoring of released animals is essential to ascertain the success of otherwise of the trial. The technique and protocols would be reviewed during and after the trial.

3.10 Specific conservation objective 10

Ensure that captive population(s) are used to support education and research elements of the Recovery Plan.

Performance criteria

Actions required to achieve objective

3.10.1 Use captive animals to heighten community understanding of the conservation of D. impar and its grassland habitat

Well-interpreted displays of threatened species is an acknowledged role of zoos in conservation, with the aim of increasing visitor understanding of the respective threats and solutions. The Victorian Action Statement recommended establishment of a public display and this is now in place at Melbourne Zoo, using animals rescued from doomed grassland sites under an agreed salvage protocol (Hawkes in press). A similar public display is being considered for the ACT, at the Tidbinbilla Nature Reserve.

3.10.2 Use captive populations to conduct biological studies

The extent to which captive populations could be used for behavioural studies to date has been very limited because of the difficulty of simulating natural environmental conditions. The Melbourne Zoo is currently constructing larger outdoor enclosures which may provide better conditions for both breeding and the study of behaviour for the animals. Further uses of the animals at Tidbinbilla should be investigated.

3.10.3 Undertake research leading to successful captive breeding

This goal was achieved at Melbourne Zoo in 1998 and further captive breeding is being pursued (Banks & Hawkes in prep.).

3.10.4 Provide interim housing for any translocated animals if required

A suitable facility has been established at Melbourne Zoo, where animals rescued from doomed grassland sites (under an agreed salvage protocol) are currently housed. In addition, a facility at VUT (Werribee) has been proposed for lizards salvaged from the Albion site. If translocations are proposed in the future, then these facilities may be required to provide short-term accommodation.

4. implementation Schedule and costing

Implementation Schedule and Costing Implementation Schedule and Costing Implementation Schedule and Costing Implementation Schedule and Costing

* Potential sources of funds to which applications may be made include NHT and industry sponsors

Note: Not all actions are fully costed at this stage. Generally, costs are indicated only where some indication has been given that funds may be available. Other actions remain uncosted, for a number of reasons:

  • All actions are dependent upon availability of funds and, in some cases, students to undertake research.
  • The total cost of survey work will be dependent on the results of the habitat surveys.
  • The total cost of managing populations will not be known until distribution is determined and options for sympathetic management have been investigated and implemented.
  • South Australian monitoring is dependent upon locating an extant population(s).
  • Some actions may also be undertaken under another program (or part thereof), but work may also address this Striped Legless Lizard recovery action.
  • Some actions are not able to be fully implemented until other actions produce guidelines and/or methodologies.

5. Preparation details

5.1 Persons responsible for the preparation of this Plan

Warwick J. S. Smith
Threatened Species Officer
Southern Zone, NSW National Parks & Wildlife Service
PO Box 2115, Queanbeyan, NSW 2620
Ph: (02) 6298 9728
Fax: (02) 6299 4281
Email: warwick.smith@npws.nsw.gov.au

Peter Robertson
Wildlife Profiles Pty. Ltd.
PO Box 500, Heidelberg VIC 3084
Ph: (03) 9499 6897
Fax: (03) 9499 6865
Email: wildlife.profiles@bigpond.com

5.2 Review date

This Recovery Plan is due for review in 2003.

5.3 Contacts

Chris Banks
Convenor, Victorian Striped Legless Lizard Working Group & National Recovery Team
Curator of Herpetofauna, Invertebrates & Education Animals, Melbourne Zoo
PO Box 74, Parkville, Vic. 3052
Ph: (03) 9285 9491
Fax: (03) 9285 9360
Email: cbanks@zoo.org.au

Peter Copley
Resource Management Branch, Department of Environment Heritage and Aboriginal Affairs
GPO Box 1047, Adelaide, SA 5001
Ph: (08) 8204 8781
Fax: (08) 8204 8889
Email: pcopley@denr.sa.gov.au

James Dawson
Threatened Species Officer
Southern Zone, NSW National Parks & Wildlife Service
PO Box 2115, Queanbeyan, NSW 2620
Ph: (02) 6298 9728
Fax: (02) 6299 4281
Email: james.dawson@npws.nsw.gov.au

Marjo Rauhala
Wildlife Ecologist
Wildlife Research & Monitoring Unit, Environment ACT
PO Box 144, Lyneham ACT 2602
Ph: (02) 6207 2114
Fax: (02) 6207 2122
Email: marjo_rauhala@dpa.act.gov.au

Mike Saxon
Manager, Threatened Species Unit
Southern Zone, NSW National Parks & Wildlife Service
PO Box 2115, Queanbeyan, NSW 2620
Ph: (02) 6298 9715
Fax: (02) 6299 4281
Email: michael.saxon@npws.nsw.gov.au

David Shorthouse
Manager, Wildlife Research & Monitoring Unit, Environment ACT
PO Box 144, Lyneham ACT 2602
Ph: (02) 6207 6379
Fax: (02) 6207 2122
Email: david_shorthouse@dpa.act.gov.au

Alan Webster
Flora and Fauna Planner
Port Phillip Area, Department of Natural Resources & Environment
PO Box 41, East Melbourne VIC. 3002
Ph: (03) 9412 4398
Fax: (03) 9412 4623
Email: alan.webster@nre.vic.gov.au

6. References

Note: See ARAZPA 1996 for an extensive bibliography relevant to D. impar.

7. Appendices

7.1 Appendix A: Current conservation status and relevant legislation

7.1.1 Current conservation status

International
IUCN (1996)

Vulnerable

ANZECC (1991, 1995)

Vulnerable

National
Schedule 1, Part 2 of the Endangered Species Protection Act 1992 (Commonwealth)

Vulnerable

Action Plan for Australian Reptiles (Cogger et al. 1993)

Vulnerable

Australian Capital Territory
Section 21 of the Nature Conservation Act 1980, Determination No. 29 of 1996, and Determination No. 89 of 1997.

Vulnerable

Schedule 6 of the Nature Conservation Act 1980.

Special Protection Status Species

New South Wales
Schedule 2 of the Threatened Species Conservation Act 1995

Vulnerable

South Australia
National Parks and Wildlife Act 1992

Under consideration for listing as Endangered

Victoria
Schedule 2 of the Flora and Fauna Guarantee Act 1988.

Threatened Taxon - Action Statement prepared 1992, due for review 1994

Threatened Fauna in Victoria - 1999 (NRE 1999)

Endangered

7.1.2 Relevant legislation

The following legislation has a direct impact on the conservation of D. impar:

7.2 Appendix B: Population cluster approach to D. impar conservation

Extracted from:ARAZPA (1996). Population and Habitat Viability Assessment (PHVA) for the Striped Legless Lizard (Delma impar). Based on a workshop held in Canberra, Australia. 30 July - 2 August 1996. Published by the Australasian Regional Association of Zoological Parks and Aquaria, ACT Parks and Conservation Service, Striped Legless Lizard Working Group, and Conservation Breeding Specialist Group (SSC/IUCN).

Goals

Objective

Develop a conservation strategy for conservation of D. impar, based on conservation of groups of populations throughout its geographic range.

Justification of objective

Primary principles of conservation biology, both endorsed here for D. impar, are:

  1. specific habitat adaptations throughout the geographic range, as reflected in genetic differentiation between areas, should be preserved to ensure the evolutionary viability of the species;
  2. where a species has been fragmented into disconnected populations across its geographic range, populations should be protected across that range to guard against unpredicted events that eliminate populations in a region.

We need to ensure we maintain/do not lose genetic variation across the range of the species. This may be achieved by identifying relative homogeneous groups of populations and ensuring that these entities are maintained throughout time. The approach adopted in this document is to identify groups of populations, each here termed a 'metapopulation' or 'cluster', which are deemed to be adapted to the habitat characteristics of a region, and will contain the unique genetic material characteristic of that region. (Previous genetic studies suggest that there is little genetic variation between populations within a geographic region.) A cluster may contain a single population, but more commonly will consist of two or more populations. Each cluster needs to be conserved, primarily as an evolutionary important unit, but also as a guard against large-scale catastrophe. This approach satisfies both conservation principles above.

These tenets have been incorporated in an operational objective to ensure conservation of D. impar: 'to ensure survival of all metapopulations with less than 1% risk of extinction of each metapopulation in 100 years.' The premise is that the maintenance of a viable metapopulation for each defined geographic region will conserve the species and its incumbent genetic variation within that region, and metapopulations together will conserve the species.

Steps to achieve objective

  1. Delineate clusters of D. impar populations across its geographic range.
  2. Describe the populations comprising each cluster; their biological and management status.
  3. Investigate the viability of each individual cluster, and of populations within clusters, using the Population Viability Assessment modelling approach.
  4. Generate a series of explicit recommendations detailing the actions needed to conserve D. impar.

Section 1. Clusters

Criteria for formation of clusters

Clusters have been tentatively defined using geographic and environmental criteria to represent areas of similar habitat. Of the seventeen potential clusters, we have information about the genetic composition of only three. There is a need to further investigate genetic variation between populations to ensure complete representation of the range of differentiation within the species. To complement this research, multivariate analysis of habitat variables should be employed to identify similar populations and to review the composition of clusters.

Potential clusters

Victoria
South Australia
NSW
ACT

Section 2. Populations

A population is defined for the purposes herein as a group of individuals capable of interbreeding naturally.

The modelling approach used to assess the viability of the core conservation entities, the clusters, requires detailed information on all D. impar populations. This detail includes population size, area of habitat, land tenure, and current management. The spatial location of populations is shown on Figure 1, and the information on each population can be found in Table 4.1 and Table 4.2. In many instances this information is incomplete, and further research or monitoring is required to fill these gaps. Particularly important are improved detection techniques for the species, allowing more accurate population estimates of the species. This and other explicit recommendations can be found in Section 4.

In the absence of complete information for each population, certain population characteristics were estimated to permit the PHVA process to continue. Where this has been done, the logic followed and the underlying assumptions have been included to provide a full explanation of the process. Two population characteristics of crucial importance to the modelling process were not known; population sizes and carrying capacity of individual areas of habitat. The rationale used to estimate these parameters is detailed below.

Population estimates

Estimates of population size in entire patches were based on the numbers of individuals caught in traps within a patch. Consequently it was necessary to determine the area surrounding a standard trapline from which the trapped animals came, i.e. the trap catchment area. With this information, trap numbers could be converted to a density for the trap catchment area, and thence to a patch density by combining information from all traps in the patch. Two approaches were used to determine trap catchment areas;

  1. Trapline Catch Records. An initial assumption was that a cross-pattern trapline (as used in ACT) had a minimum catchment area of 0.25 ha. Data from the repeat trapping of the 20ha AGSO site was used to estimate the maximum size. The first trapping of the site with two traplines yielded 5 animals per trapline. Trapping effort was subsequently increased to 11 traplines. If the catchment area for a trapline were significantly larger than 0.25 ha, perhaps up to 10 ha, then the number of animals yielded per trapline by the second trapping effort would have been much less than 5, as animals from the new trapline areas would already have been removed by the first two traplines. Numbers of animals caught per trapline in the second trapping were similar to those in the first, suggesting that the trapline catchment area was not much bigger than the extent of the trap, 0.25 ha. From this information trapline catchment area was taken to be 0.5ha allowing a degree of conservatism.
  2. Animal Movement Characteristics. Again the initial assumption was that a trapline had a minimum catchment area of 0.25 ha. Then information on the extent that D. impar move was used to estimate from how far outside the trapline area animals may move to encounter a trap. Records show that D. impar are relatively active small reptiles, with 20m the approximate mean distance which individuals have been recorded moving. Consequently, because only half of the potential animals may move towards the trapline, an extra 10m was added around the trapline area, giving a trapline catchment area of 0.5 ha.

Patch densities from trap catchment densities

The concordance of these two approaches in their estimates of the trapline catchment area give confidence that it is a reasonable approximation of the true catchment area. It should also be noted that both these approaches are based on the assumption that the trapline catches 100% of animals within its catchment area. This is unlikely to be correct, making all density estimates conservative.

Density estimates were obtained for each trapline within a patch, using the maximum number of individuals caught at each trap in any trapping period. Records for traps which caught no animals were also included. A mean was taken of these density estimates and applied to the total area of the patch; the traplines locations being assumed to be representative of conditions in the patch. In many instances traplines were located randomly through the patch and so the representative assumption is valid. In other cases, where there has been trapline positioning in selected areas, this may not be valid and populations may be overestimated.

Carrying capacity estimates

Carrying capacity (K) has not been measured for any D. impar population. This demographic characteristic is necessary for the PHVA process and so it had to be estimated. Two pieces of information provide some insight into K for the group of populations within a cluster; the maximum population density, and the variability of population densities.

Minimum K

One of the assumptions underlying the grouping of populations within a cluster is that there is a degree of similarity in environmental and habitat conditions within that cluster. Consequently, although some populations may have low densities perhaps as a result of more intense predation or disturbance, all populations have the potential of matching the K of the densest population in the cluster, given appropriate management. So the highest population density in a cluster has been used to calculate a K value for each population. This was deemed to be the minimum K value because density estimates were based largely on adult captures, with the survey method not sampling the whole population.

Maximum K

The variability of population densities in a cluster, and the relationship of this variability to habitat condition, can tell us how resource limited populations may be. If there is a strong correlation between density and habitat quality, this suggests that populations in the best quality habitat may be resource limited and close to K. If, conversely, there is no such relationship, the populations may be predation or disturbance limited, and not close to K. Inspection of this information for the ACT cluster revealed a weak relationship between population density and habitat quality, and on this basis the maximum value for K was taken at twice minimum K.

Techniques for managing small populations

We have introduced this topic because of the very nature of D. impar populations which are small, fragmented and often close to urban situations. They are therefore more likely to be suffering from loss of populations through urban expansion or from other pressures which act on small populations. It is likely that management for long-term viability will involve some form of interventionist management. This may include translocations, supplementation (movement of individuals between populations), habitat restoration or head starting to reduce juvenile mortality.

Our recommendation to carry out a trial translocation is based on the benefits it may bring (providing information on the potential success or other wise of translocations) and the likely possibility that populations will be lost and animals may need to be salvaged from sites prior to habitat loss. Habitat loss may be due to causes including development, fire, flood or other significant catastrophe. This situation has already occurred at a number of sites. We do not advocate the haphazard movement of animals without initial investigation.

Two justifications of trialing this technique are:

Section 3. Assessment of the viability of clusters and populations

Further modelling, via PHVA analyses, needs to be completed to assess the viability of clusters and refine management within them. However, we consider that the population and life-history data presently available are inadequate to enable any such analyses to be reliable indicators, and urge that these data are collected as a matter of priority.

Section 4. Recommendations for conservation of D. impar

Note: not in any priority order.

Research
Management
Techniques for managing viable populations
Monitoring

Note: Tentative proposed cluster boundaries are shown on Map 1 at the end of this report.

7.3 Appendix C: Interim management guidelines currently recommended by NRT

Prior to the finalisation of guidelines for the management of sites supporting Delma impar, the following comment gives a preliminary overview of the type of measures needed to maintain suitable habitat characteristics at sites supporting populations of the species (taken from Coulson 1995).

The availability of suitable grassland habitat is critical to the conservation of the Striped Legless Lizard. Evidence from the ACT suggests that the origin and floristics of a grassland may be less important than its current structure in determining its suitability as habitat. Grassland that is in poor condition due to heavy grazing, for example, can recover its structure rapidly after grazing has ceased. These recovered areas can provide habitat for individuals that have persisted in refugia (eg. drainage lines) and have later recolonised the area, or for individuals that are translocated to reinforce or re-establish a population.

The central aim in managing grasslands as habitat for the Striped Legless Lizard should be to provide adequate structure, particularly vertical cover, and to minimise mowing, grazing and fire, and cease cultivation and tree planting.' Broad management guidelines for sites known to support populations of the species, suggested by Dorrough (1996), include:

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