National Recovery Plan for the Giant Gippsland Earthworm Megascolides Australis
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National Recovery Plan for the Giant Gippsland Earthworm Megascolides australis Beverley D. Van Praagh and Alan L. Yen Prepared by Beverley Van Praagh (INVERT-ECO) and Alan Yen (Department of Primary Industries Victoria) Published by the Victorian Government Department of Sustainability and Environment (DSE) Melbourne, October 2010. © The State of Victoria, Department of Sustainability and Environment 2010 This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act 1968. Authorised by the Victorian Government, 8 Nicholson Street, East Melbourne. ISBN 1 74152 375 3 (online) This is a Recovery Plan prepared under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999, with the assistance of funding provided by the Australian Government. This Recovery Plan has been developed with the involvement and cooperation of a range of stakeholders, but individual stakeholders have not necessarily committed to undertaking specific actions. The attainment of objectives and the provision of funds may be subject to budgetary and other constraints affecting the parties involved. Proposed actions may be subject to modification over the life of the plan due to changes in knowledge. Disclaimer This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence that may arise from you relying on any information in this publication. An electronic version of this document is available on the Department of Sustainability, Environment, Water, Population and Communities website: www.environment.gov.au For more information contact the DSE Customer Service Centre 136 186. Citation:Van Praagh, B. and Yen, A. (2010). National Recovery Plan for the Giant Gippsland Earthworm Megascolides australis. Department of Sustainability and Environment, East Melbourne. Cover photograph: Giant Gippsland Earthworm by Beverley Van Praagh 1 Contents Summary ...........................................................................................................................3 Species Information...........................................................................................................3 Description ...........................................................................................................3 Distribution...........................................................................................................3 Population information.........................................................................................5 Habitat ..................................................................................................................6 Decline and threats ...............................................................................................7 Recovery Information .....................................................................................................10 Strategy for Recovery.........................................................................................10 Program Implementation....................................................................................10 Program Evaluation............................................................................................10 Recovery Objectives...........................................................................................11 Recovery Objectives, Performance Criteria and Actions - Summary................15 Implementation Costs.........................................................................................20 Role and Interests of Indigenous People ............................................................20 Biodiversity Benefits..........................................................................................20 Social and Economic Impacts ............................................................................20 Management Practices........................................................................................21 Affected Interests ............................................................................................................21 Acknowledgments...........................................................................................................22 Recovery Action Implementation Timetable ..................................................................23 Appendix 1: Background Information for the Giant Gippsland Earthworm .................24 Species Information.........................................................................................................24 Description .........................................................................................................24 Life history and population structure .................................................................24 Recovery Information .....................................................................................................26 Existing conservation actions.............................................................................26 References .......................................................................................................................28 Figure 1. Distribution of the Giant Gippsland Earthworm...............................................4 2 Summary The Giant Gippsland Earthworm (Megascolides australis) is endemic to an area of approximately 40,000 ha in the western Strzelecki Ranges of south and west Gippsland, Victoria. It has a fragmented distribution and occurs predominantly in permanent pasture used for dairying. Populations are generally restricted to small patches of suitable moist habitat including creek banks, soaks, and wet south-facing hillslopes. The life history of the species, including long life span, low reproductive and recruitment rates, and low dispersal ability, make the fragmented populations susceptible to environmental disturbances and catastrophic events. Anecdotal information regarding historical distribution patterns suggests that numbers have declined and the range of the species has contracted, probably due to farming activities and infrastructure development, although precise factors responsible for this decline are unclear. Major threats to the species include actions which cause changes to the local hydrology and both physical and chemical disturbances. The Giant Gippsland Earthworm is listed as Vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 and as Threatened under the Victorian Flora and Fauna Guarantee Act 1988. About 90 hectares of its habitat has also been listed on the register of the National Estate (Coy 1991). This national Recovery Plan for the Giant Gippsland Earthworm is the first recovery plan prepared for the species. The Plan details the species’ distribution, habitat, threats, and recovery objectives and actions necessary to ensure the long-term survival of the Giant Gippsland Earthworm. More detailed information on the ecology, conservation status, and implementation and costs of recovery can be found in Appendices 1 and 2 appended to this plan. Species Information Description The Giant Gippsland Earthworm (Megascolides australis) belongs to the family Megascolecidae. The species is elongate and cylindrical with 300-500 segments. The anterior third of the body is deep purple/ while the remainder of the body is a pale pink- grey, fleshy colour. M. australis can reach lengths up to 150 cm with an average size and diameter of around 80 cm and 2 cm respectively. Weights up to 400 g have been recorded, although the average is closer to 200 g (Van Praagh 1992, 1994). Newly hatched earthworms are around 18 cm long. While there have been old reports in the literature of worms reaching lengths of over three metres, no specimens of this size have been recorded during the past 15 years. McCoy (1878) provides a full description of the species, while Spencer (1888) described its morphology, and Jamieson (1971) elaborates on the systematics of the species. Distribution M. australis is restricted to a relatively small region of south and west Gippsland, Victoria (Figure 1), in an area roughly bound in the north by Warragul, and in the south by Loch and Korumburra. Mt Worth represents the most easterly point of distribution. The most southerly confirmed record occurs around Kernot and Almurta. There is little information regarding the historical distribution of the species. The extant distribution 3 of M. australis was initially determined by questionnaires completed by local residents in the late 1970s (Smith & Peterson 1982). The Atlas of Victorian Wildlife contains records of the M. australis as far south as Archies Creek. However this record and several others around Blackwood Forest and Glen Forbes are unsubstantiated. The species does not occur in sandy soils found west of Kernot, although there is a specimen in the Museum Victoria collection with label information indicating that it was collected at Queensferry in 1877. Victoria # # ## # # ## # ## # ## # W# arragul # # # ## # ## # ## ## ## # ## # ## ## # # # #### # # # # # # # # # ## # # # # # # ### # # # # # # # # # # # # # # ### # ## # # # #### ## # # # # # # # # # ## # # # ### ### # # # # ## # # # # ## # ## ## # ## # # ### #### # # # # # # # # Loch# # ## # # # # # # # # ## # ### #### # ## # # # ## # # ## # # # # #Korumburra # # # #