Biodiversity

Species Profile and Threats Database


For information to assist proponents in referral, environmental assessments and compliance issues, refer to the Policy Statements and Guidelines (where available), the Conservation Advice (where available) or the Listing Advice (where available).
 
In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.

EPBC Act Listing Status Listed as Critically Endangered
Listing and Conservation Advices Commonwealth Listing Advice on Dryococelus australis (Lord Howe Island Phasmid) (Threatened Species Scientific Committee, 2002j) [Listing Advice].
 
Recovery Plan Decision Recovery Plan required, included on the Commenced List (1/11/2009).
 
Adopted/Made Recovery Plans Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007b) [Recovery Plan].
 
Other EPBC Act Plans Threat abatement plan to reduce the impacts of exotic rodents on biodiversity on Australian offshore islands of less than 100 000 hectares 2009 (Department of the Environment, Water, Heritage and the Arts (DEWHA), 2009u) [Threat Abatement Plan].
 
Federal Register of
    Legislative Instruments
Inclusion of species in the list of threatened species under section 178 of the Environment Protection and Biodiversity Conservation Act 1999 (04/07/2002) (Commonwealth of Australia, 2002b) [Legislative Instrument].
 
State Government
    Documents and Websites
NSW:Lord Howe Island Phasmid - profile. Lord Howe Island Phasmid - profile. (Department of Environment and Climate Change (NSW) (DECC), 2005) [Internet].
NSW:Lord Howe Island Phasmid - endangered species listing. NSW Scientific Committee - final Determination (NSW Department of Environment, Climate Change and Water (NSW DECCW), 1996a) [Internet].
State Listing Status
NSW: Listed as Critically Endangered (Threatened Species Conservation Act 1995 (New South Wales): December 2013 list)
Non-statutory Listing Status
IUCN: Listed as Critically Endangered (Global Status: IUCN Red List of Threatened Species: 2013.1 list)
Scientific name Dryococelus australis [66752]
Family Phasmatidae:Phasmatodea:Insecta:Arthropoda:Animalia
Species author Montrouzier, 1855
Infraspecies author  
Reference ANZECC Threatened Fauna List May 2000
Distribution map Species Distribution Map

This is an indicative distribution map of the present distribution of the species based on best available knowledge. See map caveat for more information.

Illustrations Google Images
http://www.zoo.org.au/newspage.cfm?p=567&CFID=1949977&CFTOKEN=1397094

Scientific name: Dryococelus australis

Common names: Lord Howe Island Phasmid, Land Lobster

Phasmids from Balls Pyramid appear morphologically identical to museum specimens of Dryococelus australis collected from Lord Howe Island. There is evidence that Balls Pyramid and Lord Howe Island have never been linked above water, and it is not clear how a large, flightless stick-insect may have dispersed between them, however, transportation by seabirds as nesting material is a possibility. Molecular studies of genetic variability utilising dead animals or spent egg cases may yield some insights into the origin of the Balls Pyramid population and the length of time that it has been separated from the Lord Howe Island population (Priddel et al. 2003).

The Lord Howe Island Phasmid is a large, heavy-bodied and flightless stick-insect. Females have a body length to 12 cm and males to 10.6 cm. Males have longer and thicker antennae, greatly enlarged and spined hind legs and a narrower abdomen which lacks the ovipositor of the female (Gurney 1947; Lea 1916). Adults are a dark, golden-brown colour with a conspicuous cream stripe along the abdomen (Priddel et al. 2003), and have largely nocturnal habits (Pain 2006). Juvenile animals are bright green (DECC 2005) and active by day (Pain 2006). Eggs are beige in colour with a raised, reticulate pattern (Priddel et al. 2003).

The Lord Howe Island Phasmid is endemic to the Lord Howe group of islands (the Lord Howe Island Group). The Lord Howe Island Group consists of the main island (Lord Howe Island) and a number of smaller outlying groups of islands, including Balls Pyramid. The Lord Howe Island Phasmid was formerly abundant on Lord Howe Island (Etheridge 1889), with as many as 68 individuals found inside a single hollow (Lea 1916). It disappeared rapidly from the island after the introduction of Black Rats (Rattus rattus) in 1918 (Priddel et al. 2003; TSSC 2002j), and is now considered extinct on the main island (DECC 2007).

 

In the 1960s, three dead Lord Howe Island Phasmids were found on Balls Pyramid, a volcanic spire 23 km southeast of Lord Howe Island, which is free of rats. Since then there have been numerous unsuccessful attempts to locate live individuals, and it was not until February 2001 that live individuals were found (Priddel et al. 2003; TSSC 2002j). A second, follow-up survey conducted in March 2002 also found live individuals (Priddel et al. 2003).

The current known extent of occurrence for the Lord Howe Island Phasmid is 180 m², based on the total area occupied by the shrubs on which the insects have been found (Priddel et al. 2003).

 

The Lord Howe Island Phasmid is currently known from only one location on Balls Pyramid.

 

A captive population of several dozen breeding adults at Melbourne Zoo forms part of a breeding program aimed at re-introduction of the phasmid onto Lord Howe Island, as identified in the Lord Howe Island Biodiversity Management Plan (DECC 2007).

The size of the population on Balls Pyramid is not known but, given the limited extent of potential habitat, it is probably very small. Only three individuals were seen in 2001 and 24 in 2002 (Priddel et al. 2003). Data are limited, but it appears that population size may vary considerably between years, with rainfall thought to be a determining factor (Priddel et al. 2003).

On Lord Howe Island, the phasmid formerly inhabited forested areas in the trunk hollows of living trees, particularly those made by larvae of the Large Longicorn Beetle (Agrianome spinicollis). Particular hollows appeared to be occupied for many years (Lea 1916).

On Balls Pyramid there are no trees present, and therefore no tree hollows for the phasmid to occupy. All phasmids have been found on Melaleuca howeana, the only shrub species present on Balls Pyramid. The single terrace occupied by the phasmid is kept moist by water seeping through a seam in the rock face. The moisture has promoted the establishment and growth of several plant species including a grass (Sporobolus virginicus), a sedge (Cyperus lucidus) and two herbs (Achyranthes aspera and Tetragonia tetragonioides), as well as M. howeana. The insects appear to be sheltering in cavities formed in accumulated debris from these plants. The total area occupied by the shrubs on which the phasmids were found measures about 30 m x 6 m (Priddel et al. 2003).

The combination of a large shrub, damp conditions and lush plant growth is extremely unusual on Balls Pyramid, where bare rock or dry soil generally predominates, and examination of air photos has not revealed any other likely patches of habitat (Priddel et al. 2003).

It previously appeared that the Lord Howe Island Phasmid released its eggs while suspended above the ground, like most other stick-insects (Lea 1916). However, observations from the captive breeding program at Melbourne Zoo indicate that the Lord Howe Island Phasmid may bury a batch in the soil (Pain 2006). The sex ratio appears to be strongly skewed towards females, with the ratio of males to females on Balls Pyramid being 1:7 (Priddel et al. 2003). Historical accounts of the Lord Howe Island Phasmid indicate that males, although not uncommon, were far less numerous than females (Etheridge 1889). It is speculated that the species may be able to reproduce by parthenogenesis, a process common among phasmids by which unfertilised eggs hatch into females (Priddel et al. 2003).

Individuals located on Balls Pyramid have been observed grazing on the new leaf tips of M. howeana. It is not known what plant species they formerly grazed on Lord Howe Island (Priddel et al. 2003). In adults (Pain 2006), feeding appears to occur at night (Lea 1916; Priddel et al. 2003).

The population is very small and restricted to a tiny patch of apparently suboptimal habitat, and therefore has a high risk of extinction through random, unpredictable events.

The habitat occupied by the Lord Howe Island Phasmid is extremely fragile and unstable, and any disturbance (including in situ scientific research) could be catastrophic for the species (Priddel et al. 2003).

Morning Glory (Ipomoea cairica), an invasive vine, poses a threat to M. howeana, the only known food plant of the phasmid on Balls Pyramid. All Morning Glory plants in the immediate vicinity of the phasmid population were recently carefully removed (Priddel et al. 2003).

Balls Pyramid is currently rat-free and the potential introduction of rats to the island is a threat to the phasmid (DECC 2007).

Other threats to the Lord Howe Island Phasmid include the potential introduction of non-native invertebrates, such as the Red Imported Fire Ant (Solenopsis invicta) and the Yellow Crazy Ant (Anoplolepsis graciliopes), and the potential loss of habitat due to climate change (DECC 2007). The phasmid is also a potential target for illegal poaching by insect collectors (Priddel et al. 2003).

Nesting seabirds on Balls Pyramid have been known to incorporate Lord Howe Island Phasmids into their nests (Smithers 1970).

The Lord Howe Island Biodiversity Plan (DECC 2007), a nationally-approved recovery plan, recognises the need for priority recovery actions specifically for the Lord Howe Island Phasmid. These include restricting access to Balls Pyramid, controlling Morning Glory (I. cairica) on Balls Pyramid, monitoring phasmid population numbers on Balls Pyramid, maintaining captive breeding programs and reintroducing the phasmid to the main island (DECC 2007). These actions are intended to be implemented within three years (DECC 2007).

In 2003, a pair of adult Lord Howe Island Phasmids was taken to Melbourne Zoo in an attempt to breed them in captivity. The female began laying eggs in February 2003 and the first hatchlings emerged in September 2003 (McGhee 2007). Several new generations have since been produced and the population in 2005 consisted of several dozen breeding adults (DECC 2007). The aim of the breeding program is to "secure the immediate survival of the species and to produce the animals needed for its subsequent re-introduction back onto Lord Howe Island" (DECC 2007).

In addition to actions aimed specifically at recovery of the Lord Howe Island Phasmid, the Lord Howe Island Biodiversity Plan (DECC 2007) also contains a number of other priority actions which address threats to the phasmid, including: quarantine and pest eradication measures to control the introduction or eradication of introduced weeds, pests and diseases; measures to reduce the impact of illegal collecting; monitoring the consequences of climate change and developing contingency plans for affected species; as well as programs to protect and enhance species habitat and encourage positive appreciation of biodiversity (DECC 2007).

The Lord Howe Island Biodiversity Plan, developed by the NSW Department of Environment and Climate Change (DECC) in 2007, and adopted under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) in 2008, encompasses threats and management actions relevant to the Lord Howe Island Group's overall biodiversity, including the Lord Howe Island Phasmid.

The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.

Threat Class Threatening Species References
Biological Resource Use:Hunting and Collecting Terrestrial Animals:Illegal hunting/harvesting and collection Commonwealth Listing Advice on Dryococelus australis (Lord Howe Island Phasmid) (Threatened Species Scientific Committee, 2002j) [Listing Advice].
Ecosystem/Community Stresses:Indirect Ecosystem Effects:Restricted geographical distribution (area of occupancy and extent of occurrence) Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007f) [State Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Ipomoea cairica (Coastal Morning-glory, Morning Glory, Mile-a-minute, Five-leaved Morning Glory) Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007f) [State Recovery Plan].
Commonwealth Listing Advice on Dryococelus australis (Lord Howe Island Phasmid) (Threatened Species Scientific Committee, 2002j) [Listing Advice].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation Rattus rattus (Black Rat, Ship Rat) The threat posed by pest animals to biodiversity in New South Wales (Coutts-Smith, A.J., P.S. Mahon, M. Letnic & P.O. Downey, 2007) [Management Plan].
Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007f) [State Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive and Other Problematic Species and Genes:Predation, competition, habitat degradation and/or spread of pathogens by introduced species Commonwealth Listing Advice on Dryococelus australis (Lord Howe Island Phasmid) (Threatened Species Scientific Committee, 2002j) [Listing Advice].
Species Stresses:Indirect Species Effects:Low numbers of individuals Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007f) [State Recovery Plan].
Commonwealth Listing Advice on Dryococelus australis (Lord Howe Island Phasmid) (Threatened Species Scientific Committee, 2002j) [Listing Advice].

Department of Environment and Climate Change (NSW) (DECC) (2005). Lord Howe Island Phasmid - profile. Lord Howe Island Phasmid - profile. [Online]. Available from: http://www.threatenedspecies.environment.nsw.gov.au/tsprofile/profile.aspx?id=10881. [Accessed: 27-Mar-2008].

Etheridge, R. (1889). The general zoology of Lord Howe Island. Australian Museum Memoirs. 2:3-42.

Gurney, A.B. (1947). Notes on some remarkable Australian walkingsticks, including a synopsis of the genus Extatosoma (Orthoptera: Phasmatidae). Annals of the Entomological Society of America. 40:373-396.

Lea, A.M. (1916). Notes on the Lord Howe Island phasma, and on an associated longicorn beetle. Transcripts, Proceedings of the Royal Society of South Australia. 40:145-147.

McGhee, K (2007). The good fight. Australian Geographic. 88:104-117.

NSW Department of Environment and Climate Change (NSW DECC) (2007b). Lord Howe Island Biodiversity Management Plan. [Online]. Sydney, NSW: NSW Department of Environment and Climate Change. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/recovery/lord-howe/index.html.

Priddel, D., N. Carlile, M. Humphrey, S. Fellenberg & D. Hiscox (2003). Rediscovery of the 'extinct' Lord Howe Island stick-insect (Dryococelus australis (Montrouzier)) (Phasmatodea) and recommendations for its conservation. Biodiversity and Conservation. 12(7):1391-1403. [Online]. Available from: http://www.ingenta.com/isis/searching/Expand/ingenta?pub=infobike://klu/bioc/2003/00000012/00000007/05101026.

Smithers, C.N. (1970). On some remains of the Lord Howe Island Phasmid (Dryococelus australis (Montrouzier)) (Phasmida) from Ball's Pyramid. Entomologist's Monthly Magazine. 105:252.

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This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.

Citation: Department of the Environment (2014). Dryococelus australis in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Thu, 18 Sep 2014 12:31:53 +1000.