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 Vulnerable as Christinus guentheri
Recovery Plan Decision Recovery Plan required, included on the Commenced List (1/11/2009).
 
Adopted/Made Recovery Plans Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010) [Recovery Plan] as Christinus guentheri.
 
Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007b) [Recovery Plan] as Christinus guentheri.
 
Policy Statements and Guidelines Survey guidelines for Australia's threatened reptiles. EPBC Act survey guidelines 6.6 (Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC), 2011m) [Admin Guideline].
 
Federal Register of
    Legislative Instruments
Declaration under s178, s181, and s183 of the Environment Protection and Biodiversity Conservation Act 1999 - List of threatened species, List of threatened ecological communities and List of threatening processes (Commonwealth of Australia, 2000) [Legislative Instrument] as Christinus guentheri.
 
State Government
    Documents and Websites
NSW:Lord Howe Island Gecko - profile (NSW Department of Environment, Climate Change and Water (NSW DECCW), 2005bk) [Internet].
State Listing Status
NSW: Listed as Vulnerable (Threatened Species Conservation Act 1995 (New South Wales): December 2013) as Christinus guentheri
Non-statutory Listing Status
IUCN: Listed as Vulnerable (IUCN Red List of Threatened Species: 2011.2)
Scientific name Christinus guentheri [59250]
Family Gekkonidae:Squamata:Reptilia:Chordata:Animalia
Species author (Boulenger,1885)
Infraspecies author  
Reference  
Other names Phyllodactylus guentheri [1679]
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

Pale olive-grey to dark brown heavily built reptile growing to 8 cm, peppered with dark brown and a series of six paler, W-shaped traverse markings continuous with the paler flanks, tail with a dull russet-red mid-dorsal stripe, whitish/yellow-brown below peppered with dark brown, smooth small scales, long and slender fingers and toes (Cogger 2000).

Formerly distributed on Lord Howe I., Norfolk I. and their small offshore islands in the Pacific Ocean (Cogger et al. 1993). Early reports of Norfolk I. suggest it was quite common (Cogger 1971). It currently appears to be extinct on Norfolk I. but occurs on nearby Phillip I., Nepean I. and two small rocky islets, Moo-oo Rock (Moo-oo Stone) and Bird Rock (Red Stone) (Cogger et al. 1993). Densities in some areas on Phillip I. are very high, with 34 geckoes captured from the lower branches of one small tree in a half-hour period. A population estimate for Fisherman's Hut Rock (part of Phillip I.) based on a three-night mark-recapture program was 679 individuals. Day surveys of the same area found only 10 geckoes. The population for Phillip I. is estimated to be 100 000 individuals (Cogger et al. (1983).

On Lord Howe I. it is currently restricted to a small area near the main settlement, also occurs on nearby Blackburn (Rabbit) I., Roach I. and Balls Pyramid (Cogger et al. 1993). Thought to occur on all of the Admiralty Islets, though only confirmed on Roach I., with 11 individuals collected in a one-hour survey (Cogger 1971; Cogger et al. 1993).

Tail loss is common on Phillip I., with original tails usually only found on juveniles. Loss is believed to be due to intraspecific interactions under high density situations, rather than predation. The only terrestrial predators on Phillip I. are crabs and large centipedes (Cogger et al. 1979).

Also appears as Phyllodactylus guentheri in the literature (Cogger et al. 1993).

In general, occurs in closed forest, low open woodland, tussock grassland and rocky isolates. On Blackburn I. geckoes appear to be common among small slopes of loose basalt boulders on the leeward side, especially around the bases of low, windswept trees. Fewer geckoes apparently live on the windward side, where there are few boulder piles. On the Lord Howe I. mainland they appear restricted to a single, rare habitat type behind Lagoon Beach and at the base of Malabar. The habitat consists of honeycombed beachrock partially embedded in the soil, surrounded by Howea palm forest in which there is a thick layer of humus formed by palm and other leaf litter. The surfaces of the rocks are pitted with holes averaging 1-2 cm in diameter, tunnelling deep into the matrix of the rock. Some tunnels join to form larger chambers. The tunnels appear to provid the only safe shelter site for the geckoes from vertebrate predators. The surrounding humus provides many invertebrate prey items (Cogger 1971).

On Phillip I. geckoes occurred over all parts of the island surveyed, wherever minimal cover offered protection from the sun. Maximum densities occurred on grassy coastal cliffs and among trees and vegetation on boulder slopes in the central valley. In these habitats geckoes sheltered under rocks, fallen timber and other debris. There may be a difference in habitat preferences of males and females on this island, with males predominating in relatively clear slopes beneath White Oak Trees (Lagunaria patersonia) and females predominating in the boulder slopes beneath thickets of African Olives (Olea africana). The majority of eggs were also found in African Olive thickets (Cogger et al. 1983).

On Nepean I. geckoes were found to be abundant throughout the island, sheltering beneath surface rocks and litter, and in rocky crevices during the day. At night geckoes were found actively foraging on open sand, rocky cliffs, grassy areas, and in the littoral and adjacent splash zones. The largest numbers were found on White Oak Trees (Cogger et al. 1983).

On Bird Rock and Moo-oo Rock geckoes were found sheltering beneath rocks partly embedded in the soil, in rock crevices and in particularly high densities near White Oak thickets (Cogger et al. 1983).

Nocturnal activity appears to be unrestricted by the need to thermoregulate, with the thermal activity range for the species differing little from the ambient temperature range (Cogger et al. 1983).

Two important seasonal sources of food on Phillip I. are nectar, including that of the Norfolk I. Hibiscus (Lagunaria patersonia), White Oak Trees (Lagunaria patersonia) and the Swan Plant (Gomphocarpus physocarpus), and the fruit of the succulent herb, Pigface (Cogger et al. 1979; Cogger et al. 1983; Paul Stevenson in Cogger et al. 1993). Gut contents of specimens collected from Phillip I. included bracts or leaves from flowering plants, anthers and seeds (Cogger et al. 1983).

Invertebrates also form a major part of the diet, with the following items occurring in over 20% of the guts examined (n = 17) from Phillip I.: spiders, mites, beetles, moths, caterpillars, flies, ants and wasps (Cogger et al. 1983).

A survey on Lord Howe I. in June 1966 failed to find any gravid females (Cogger 1971). Surveys conducted in the Norfolk I. complex in Nov. found some gravid females, while others retained well-developed corpora lutea and expanded convoluted oviducts, indicating recent oviposition. Males have been found undergoing active spermatogenesis in Nov. (Cogger et al. 1979).

Clutch size varies from one to three eggs, with a mean of 1.32 (n = 15) (Cogger et al. 1979). Clutches of up to seven eggs appear to be evidence for communal nesting (Cogger et al. 1983).

On Lord Howe I. eggs are placed in the tunnels in honeycomb beachrock, with new eggs laid upon the shells of hatched eggs (Cogger 1971). On Phillip I. and Nepean I. nests were found in soil beneath small to large boulders or under fallen timber (Cogger et al. 1983).

Five eggs collected from Lord Howe I. in June were taken to a laboratory and left in a dry jar on a bench experiencing temperatures of 66°F to 84°F. Two eggs hatched between 4 and 18 Jan., with others hatching on 8 and 13 Feb. and 14 Mar. Although the laying date was not known, the minimum incubation time for the eggs was from 30 to 39 weeks (Cogger 1971).

Eggs collected Phillip I. and Nepean I. in late Nov., and incubated in the laboratory had a minimum incubation time of 79-87 days, while one egg laid in the laboratory in Dec. hatched after 91 days (Cogger et al. 1983).

Eggs are soft when laid, taking the shape of the surfaces they touch and often adhering to the rock or each other, becoming thick, brittle and calcareous (Cogger 1971).

The adult sex ratio on Phillip I. is close to 1M:1F, while on Nepean I. it is 1M:1.42F. The adult to juvenile ratio on these islands was 1:0.06 and 1:0.26 respectively (Cogger et al. 1979).

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
Climate Change and Severe Weather:Habitat Shifting and Alteration:Habitat loss, modification and/or degradation Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].
Ecosystem/Community Stresses:Ecosystem Degradation:Decline in habitat quality Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or habitat degradation Oryctolagus cuniculus (Rabbit, European Rabbit) Christinus guentheri in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage (DEH), 2006ey) [Internet].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation Felis catus (Cat, House Cat, Domestic Cat) Christinus guentheri in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage (DEH), 2006ey) [Internet].
Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation Rattus exulans (Pacific Rat, Polynesian Rat) Christinus guentheri in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage (DEH), 2006ey) [Internet].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation Rattus rattus (Black Rat, Ship Rat) Christinus guentheri in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage (DEH), 2006ey) [Internet].
Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].
Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007b) [Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition, predation and/or habitat degradation Hemidactylus frenatus (Asian House Gecko) Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Grazing, tramping, competition and/or habitat degradation Capra hircus (Goat) Christinus guentheri in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage (DEH), 2006ey) [Internet].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Grazing, tramping, competition and/or habitat degradation Sus scrofa (Pig) Christinus guentheri in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage (DEH), 2006ey) [Internet].
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 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].
Invasive and Other Problematic Species and Genes:Problematic Native Species:Competition, predation and/or habitat degradation Lampropholis delicata (a skink) Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007b) [Recovery Plan].

Cogger, H.G. (1971). The reptiles of Lord Howe Island. Proceedings of the Linnean Society of New South Wales. 96 (1):23-40.

Cogger, H.G. (2000). Reptiles and Amphibians of Australia - 6th edition. Sydney, NSW: Reed New Holland.

Cogger, H.G., E.E. Cameron & R.A. Sadlier (1979). The terrestrial reptiles of islands in the Norfolk Island complex. The Terrestrial Reptiles of Islands in the Norfolk Island Complex. Page(s) 1-122. ANPWS. ANPWS, Canberra.

Cogger, H.G., E.E. Cameron, R.A. Sadlier & P. Eggler (1993). The Action Plan for Australian Reptiles. [Online]. Canberra, ACT: Australian Nature Conservation Agency. Available from: http://www.environment.gov.au/biodiversity/threatened/action/reptiles/index.html.

Cogger, H.G., R.A. Sadlier & E.E. Cameron (1983). The terrestrial reptiles of Australia's island territories.:50-52. ANPWS. ANPWS, Canberra.

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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). Christinus guentheri in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Fri, 18 Apr 2014 23:53:32 +1000.