The Recovery Plan for the Bathurst Copper Butterfly (Paralucia spinifera) 2001-2006Bathurst Copper Butterfly

NSW National Parks and Wildlife Service
Environment Australia, June 2001
ISBN 0 7313 62829

Appendix 1: Environmental Impact Assessment Guidelines and Information Sheet for the Bathurst Copper Butterfly (Paralucia spinifera Edwards and Common, 1978)

Other common name(s): Yetholme Copper Butterfly

The following information is provided to assist authors of Species Impact Statements, development and activity proponents, and determining and consent authorities, who are required to prepare or review assessments of likely impacts on threatened species pursuant to the provisions of the Environmental Planning and Assessment Act 1979. These guidelines should be read in conjunction with the NPWS Information Circular No. 2: Threatened Species Assessment under the EP and A Act: The '8 Part Test' of Significance (November 1996).

Identification of habitat

Current knowledge suggests that P. spinifera occurs only at altitudes in excess of 900 metres and requires the presence of the larval food plant Bursaria spinosa subsp. lasiophylla. Aspect, geology, vegetation overstorey species are sufficiently variable at known locations of P. spinifera to preclude their use as factors in identifying potential P. spinifera habitat. Similarly, the cryptic nature of the attendant ant, Anonychomyra itinerans, and its apparent absence from at least one P. spinifera location precludes its use as an indicator of the presence or absence of P. spinifera. It is recommended that potential habitat for P. spinifera be identified by the presence of Bursaria spinosa subsp. lasiophylla at locations above approximately 900 metres in altitude. Bursaria spinosa subsp. lasiophylla is described in Cayser et al (in press).

Survey

The adult phase of a P. spinifera may only last two weeks, however, adults may be expected to be active at a site for a number of weeks as emergence of adults is affected by intra-site microclimate variation. Survey of potential habitat for P. spinifera should be designed in cognisance of; records of adult emergence occurring between August and November, the factors affecting activity (eg. weather), the emergence of adults at nearest known sites, the sensitivity of the species to disturbance and handling, the need to ensure that the habitat is adequately sampled.

Life cycle of the species

The ecology of P. spinifera is described in the referenced literature and the Recovery Plan. P. spinifera's lifecycle includes egg, larval, pupal, and adult stages. These stages encompass a number of key elements; oviposition, larvae emergence and survival, acquisition of nutrition through grazing of host plant by larvae, diurnal and nocturnal migration between host plant and A. itinerans nest, pupation in A. itinerans nest, emergence of adults, courtship and mating, dispersal, and so on. The continuity of P. spinifera's lifecycle may be interrupted if any one of these elements is directly or indirectly affected. As the lifecycle of P. spinifera relies on a mutualistic relationship with the ant species, A. itinerans, and on the presence of the larval food plant B. spinosa subsp. lasiophylla the lifecycles of these species must be considered in assessing potential impact on P. spinifera. For example, the spacial distribution of B. spinosa subsp. lasiophylla affects its availability to larvae, which are not known to cross open ground to graze - only reaching additional plants by traversing intertwining branchlets. Accordingly, changes to the actual or effective density of B. spinosa subsp. lasiophylla through wildfire fuel reduction or by the invasion of weeds may cause early pupation due to starvation, reduced adult size and reduced fecundity. Reduced fecundity may lead to population decline and local extinction.

Threatening processes

The Threatened Species Conservation Act 1995 (TSC Act) does not list a key threatening process that affects P. spinifera. The Recovery plan identifies clearing of habitat (associated with grazing by stock or feral animals, development or land use activities), isolation of habitat, weed invasion, inappropriate fire regimes, disturbance to soils and vegetation by feral animals, loss of attendant ant, and dust generated by traffic as threats.

Viable local population of the species

Although the population of P.spinifera is small and occurs as discrete sub-populations within a restricted range, activities which result in the destruction of individuals have the potential to significantly affect the viability of a population of P. spinifera. The potential for P. spinifera sub-populations to operate as metapopulations should also be considered. Sub-population sizes may vary greatly form year to year according to variations in climate and other site factors. Accordingly, adults may be apparently absent.

A significant area of habitat

The restricted distribution of P. spinifera may be partially explained through the apparent reliance on a combination of restrictive habitat requirements, mainly its mutualistic association with A. itinerans and requirement for the larval food plant B. spinosa subsp. lasiophylla. However, both these species are more widespread than P. spinifera. It is assumed that there has been a reduction in the natural extent or distribution of this species or its habitat. Recent genetic studies allow for a recent reduction in the extent of habitat. Dexter and Kitching (unpub.) consider the population sites as refugia from past climate changes. An assessment of the effect of a proposal on habitat should consider all direct and indirect effects on the habitat of P. spinifera and on the habitat of A. itinerans and B. spinosa subsp. lasiophylla.

Isolation/fragmentation

P. spinifera has a low dispersal capability, which may present an increased risk of extinction due to the potential for the sub-populations to have inadequate levels of genetic exchange. Accordingly, isolated habitat fragments are less likely to be recolonised if local extinction does occur. In addition to habitat removal, structures or other developments may restrict movement of P. spinifera. Effect on apparently unoccupied potential habitat may reduce P. spinifera ability to respond to opportunities to occupy habitat.

Regional distribution of the habitat

The TSC Act defines region as the regions defined in the Interim Biogeographic Regionalisation of Australia. The known distribution of P. spinifera is confined to the South Eastern Highlands region.

Limit of known distribution

P. spinifera is restricted to an area between Oberon, Hartley and Bathurst on the Central Tablelands of NSW. Further survey of potential habitat may identify additional populations and range extensions.

Adequacy of representation in conservation reserves or other similar protected areas

Two of the 29 known populations of P. spinifera are located within land managed for conservation purposes by the NPWS. Although a genetic study found that the heterogeneity within populations was high and that the sub-populations were closely related (Dexter and Kitching unpub.), it is not known whether P. spinifera'sgenetic variation is adequately reserved. Similarly, in the absence of adequate population dynamic studies, it is not known whether a significant proportion of the population is reserved. The reserved sites do not represent the full range of vegetative variability, altitudinal range or geographic range.

Critical habitat

There is currently no critical habitat declared for P. spinifera.

For further information contact:

Threatened Species Unit, Central Directorate, NSW NPWS, PO Box 1967, Hurstville NSW 2220. Phone: 9585 6678. www. npws.nsw.gov.au

References

Cayser L.W. Crisp M..D. and Telford I.R.H. (Draft 1997 (in prep?) Bursaria (Pittosporaceae): A Morphometric Analysis and Revision. Dexter E. M. and Kitching R. L. Nomination for the Register of the National Estate. Australian Heritage Commission (unpublished report). Dexter E. M. and Kitching R. L. (unpublished) Microhabitat requirements of the Bathurst Copper Butterfly Paralucia spinifera (Lycaenidae) Edwards E. D. and Common I. F. B. (1978) A New Species of Paralucia Waterhouse and Turner from New South Wales (Lepidoptera: Lycaenidae) in Aust Ent Mag 5(4):65-70  

IMPORTANT DISCLAIMER

The NSW National Parks and Wildlife Service and the editor expressly disclaim all liability and responsibility to any person, whether a purchaser or reader of this document or not, in respect of anything done or omitted to be done by any person in reliance upon the contents of this document although every effort has been made to ensure that the information presented in this document is accurate and up to date.

 

THREATENED SPECIES INFORMATION

Paralucia spinifera

(Edwards and Common, 1978)

Other common name(s): Yetholme Copper Butterfly

Conservation Status

Paralucia spinifera is listed as an endangered species on Schedule 1 of the Threatened Species Conservation Act 1995. P. spinifera is also listed as a vulnerable species on Schedule 1 Part 2 of the Endangered Species Protection Act 1992 (Cwlth).

Description

P. spinifera is a small butterfly with a thick body and a wingspan of 20-30 mm. The upper sides of P. spinifera's wings are copper colored and display a purple, blue, and green iridescence when sunning. The undersides of the wings are patterned with subtle brown, black, and grey. Its black antennae are dotted with white spots, and terminate with a black tip.

Drawing of Butterfly

P. spinifera is distinguished from P. aurifera and P. pyrodiscus by the size, shape and colour of the wings, and also by a spine that extends over a joint in the forelegs.

Distribution

P. spinifera occurs on the Central Tablelands of NSW in an area generally bounded by Oberon, Hartley and Bathurst. P. spinifera is found at 29 locations, all within the local government areas of Greater Lithgow and Evans. It is possible that additional locations will be identified, and these may lie outside the currently known distribution.

Occurrences in conservation reserves

Of the twenty-nine known locations, four occur within areas managed for conservation purposes by the NPWS. The remainder occur on freehold land, and land managed by other State and local government agencies.

Habitat

P. spinifera locations occur above 900m in altitude, are generally associated with exposure to full day sun (often with a west to north aspect), and with extremes of cold such as regular winter snowfalls or heavy frosts. Geology, soils and dominant vegetation canopy species vary between locations of P. spinifera. Conversely, vegetation structure is consistent, commonly open woodland or open forest with a sparse understorey that is dominated by the shrub, Blackthorn (Bursaria spinosa subsp. lasiophylla).

Ecology

The lifecycle of P. spinifera relies on a mutualistic relationship with the ant, Anonychomyra itinerans, and on the presence of the larval food plant B. spinosa subsp. lasiophylla. The butterflies emerge between August (later at higher altitude sites) and November, with a two-week peak of activity in September. After mating, the female oviposits eggs on or in the immediate vicinity of B. spinosa subsp. lasiophylla. After hatching, the larva is attended by A. itinerans, which is thought to offer the larva predator protection and receive nutritional secretions from the larva (Dexter and Kitching unpub). Initially diurnal, the larva becomes nocturnal in the latter part of its six-to-eight week larval period. Pupation occurs in the underground nest of A. itinerans at the base of the host plant between December and February (Dunn et al. 1994). The relationship between P. spinifera, A. itinerans, and B. spinosa subsp. lasiophylla is not completely understood, but it is thought to be highly significant. Even though it is sometimes difficult to detect, A. itinerans has been recorded at almost all of the P. spinifera locations. Similarly B. spinosa subsp. lasiophylla is present at all locations of P. spinifera. Adult male P. spinifera fly rapidly at about one metre from the ground and rest with wings parted in sites exposed to full sun. Female P. spinifera fly less rapidly and tend to remain nearer to the host plant (Edwards and Common 1978). P. spinifera generally remain in the vicinity of B. spinosa subsp. lasiophylla, and are rarely observed more than 10 metres distant from the habitat.

Threats

The 29 known locations are generally small and isolated and are vulnerable to impacts from weed invasion. and control, inappropriate fire management, clearing, and overgrazing. P. spinifera's sedentary nature indicates it has a low dispersal capability, hence is unlikely to colonise new areas after its habitat has been destroyed. P. spinifera's reliance on A. itinerans, and B. spinosa subsp. lasiophylla means that factors affecting those species also affect P. spinifera. The rarity of P. spinifera makes it attractive to collectors, and collection is thought to have contributed to severe population decline at one site (Dexter and Kitching 1991).

Management

Management varies from site to site depending on the threats operating.

Recovery Plans

The recovery plan was approved in June 2001.

For Further Information contact

Threatened Species Unit Central Directorate NSW NPWS PO Box 1967, Hurstville NSW 2220 Phone 02 9585 6678 www.npws.nsw.gov.au

REFERENCES

Dexter E. M. and Kitching R. L. Nomination for the Register of the National Estate. Australian Heritage Commission (unpublished report).

Dexter E. M. and Kitching R. L. (1991) The Bathurst Copperwing, Paralucia spinifera Edwards and Common - in The Conservation Biology of Lycaenidae (Butterflies) Ed T. New Occasional Paper of the IUCN Species Survival Commission No 8.

Dunn K.L., Kitching R.L. and Dexter E. M. (1994) The Conservation Status of Australian Butterflies - A Report to the Australian National Parks and Wildlife Service.

Edwards E. D. and Common I. F. B. (1978) A New Species of Paralucia Waterhouse and Turner from New South Wales (Lepidoptera: Lycaenidae) in Aust Ent Mag 5(4):65-70

IMPORTANT DISCLAIMER

The NSW National Parks and Wildlife Service and the editor expressly disclaim all liability and responsibility to any person, whether a purchaser or reader of this document or not, in respect of anything done or omitted to be done by any person in reliance upon the contents of this document although every effort has been made to ensure that the information presented in this document is accurate and up to date.