Use of burrows by the endangered pygmy blue-tongue lizard, Tiliqua adelaidensis (Scincidae)

2003 ◽  
Vol 30 (5) ◽  
pp. 523 ◽  
Author(s):  
Tim Milne ◽  
C. Michael Bull ◽  
Mark N. Hutchinson
Keyword(s):  
Endangered Species ◽  
Conservation Management ◽  
South Australia ◽  
Early Summer ◽  
Mating Activity ◽  
Adequate Supply ◽  
Invertebrate Prey ◽  
Video Recordings ◽  
Management Scheme ◽  
Burrow Entrance

The pygmy blue-tongue lizard, Tiliqua adelaidensis, had been considered extinct until its recent rediscovery near Burra in the mid-north of South Australia. The lizards apparently rely on spider burrows with a single entrance as refuge sites. In this paper we describe observations from all-day video recordings of the entrances of burrows occupied by lizards on 31 days across the spring and early summer of 1996. The lizards spent most of each day either retreated down the burrow or basking at the burrow entrance. Early in the season, when temperatures were cooler, lizards spent more of each day basking, and more of their basking time fully emerged from the burrow, than later in the season. Results are consistent with the hypothesis that the lizards thermoregulate by moving in and out of the burrow. Lizards also fed by making short excursions from the burrow, often to catch passing invertebrate prey, although they also fed on flowers early in spring. Later in the season lizards were more likely to vacate their burrows for longer times, or to move away from their burrows, and mating activity was observed when males approached burrows occupied by females. The observations suggest that pygmy blue-tongue lizards rely heavily on burrows for many activities, and that any conservation management scheme for this endangered species will rely on maintaining an adequate supply of burrows.

scholarly journals Long and short term residence in refuge burrows by endangered pygmy bluetongue lizards

2015 ◽  
Vol 36 (2) ◽  
pp. 119-124 ◽  
Author(s):  
C. Michael Bull ◽  
Stephanie S. Godfrey ◽  
Mehregan Ebrahimi ◽  
Aaron L. Fenner
Keyword(s):  
Endangered Species ◽  
Conservation Management ◽  
South Australia ◽  
Early Spring ◽  
Entire Study Period ◽  
Short Term ◽  
Entire Study ◽  
Invertebrate Prey ◽  
Occupancy Dynamics ◽  
Native Grassland

The pygmy bluetongue lizard (Tiliqua adelaidensis) is an endangered species which is restricted to native grassland remnants in South Australia. Individuals live in vertical burrows with a single entrance from which they ambush invertebrate prey. We monitored marked burrows over two entire spring-summer seasons, the period when the lizards are active, and found that the population contained a mixture of dispersers that remained in a burrow briefly, and residents that occupy a burrow for the entire study period. There were more females than males among the residents and most of the burrow abandonment happened in the early spring, the time when male lizards probably move around to seek matings. Our study described burrow occupancy dynamics, and will assist the conservation management of this endangered species.

Scatting behaviour of the pygmy bluetongue lizard

2016 ◽  
Vol 37 (2) ◽  
pp. 207-213 ◽  
Author(s):  
Mehregan Ebrahimi ◽  
Stephanie S. Godfrey ◽  
Aaron L. Fenner ◽  
C. Michael Bull
Keyword(s):  
Endangered Species ◽  
Social Communication ◽  
Early Summer ◽  
Early Stages ◽  
Video Recordings ◽  
Burrow Entrance ◽  
Path Direction ◽  
Activity Season

We used video recordings of 29 pygmy bluetongue lizards for ten days of each month during their spring and summer activity season to observe scatting behaviour. This was possible because resident lizards rarely moved from their single entrance burrows. We used these observations to ask questions about social communication that might be relevant to conservation of this endangered species. We found lizards produced more scats in the middle of the day than earlier or later in the day, and more scats in the spring and early summer than later in the summer. Lizards moved an average of 68.54 ± 0.09 cm from their burrow entrance to deposit scats, taking an average of 2.4 min per defecation trip. They tended to use the same path direction for most defecation trips, but used more different directions if there were more close neighbours, strongly supporting a hypothesis that scats mark burrow ownership. The results suggested that conservation managers might reduce stress for relocated lizards by removing scat piles in the early stages of settlement.

The ecology of sympatric scincid lizards (Ctenotus) in arid South Australia

1998 ◽  
Vol 46 (6) ◽  
pp. 617 ◽  
Author(s):  
J. L. Read
Keyword(s):  
Home Range ◽  
Environmental Conditions ◽  
Plant Material ◽  
Reproductive Effort ◽  
Arid Zone ◽  
South Australia ◽  
Early Summer ◽  
Home Ranges ◽  
Local Species ◽  
Olympic Dam

Ctenotus skinks are the most diverse and abundant diurnal reptile genus at Olympic Dam, in the South Australian arid zone. The home range, demography, reproduction and diet of five syntopic Ctenotus species was studied over a 6-year period in chenopod shrubland. Longevity frequently exceeded three years in C. regius, four years in C. schomburgkii and five years in C. leonhardii, with a 7-year-old specimen of C. leonhardii being recorded. Females of most species tended to be larger and lived longer than males. Two eggs were typically laid by each species in early summer. Annual reproductive effort, particularly in C. leonhardii, varied considerably depending upon the prevailing environmental conditions. All local species apparently occupied home ranges, with maximum recapture radii in different species of 40–60 m. Ctenotus appear to be unspecialised insectivores, although plant material and lizards are sometimes eaten by the larger species.

Delineation of conservation units in an endangered marsupial, the southern brown bandicoot (Isoodon obesulus obesulus), in South Australia/western Victoria, Australia

2014 ◽  
Vol 62 (5) ◽  
pp. 345 ◽  
Author(s):  
You Li ◽  
Melanie L. Lancaster ◽  
Susan M. Carthew ◽  
Jasmin G. Packer ◽  
Steven J. B. Cooper
Keyword(s):  
Conservation Management ◽  
Conservation Status ◽  
South Australia ◽  
Disjunct Distribution ◽  
Conservation Units ◽  
Evolutionarily Significant Units ◽  
Population Analyses ◽  
High Conservation ◽  
Western Victoria ◽  
Evolutionary Lineages

Conservation programs for threatened species are greatly benefiting from genetic data, for their power in providing knowledge of dispersal/gene flow across fragmented landscapes and for identifying populations of high conservation value. The endangered southern brown bandicoot (Isoodon obesulus obesulus) has a disjunct distribution range in South Australia, raising the possibility that populations of the subspecies may represent distinct conservation units. In the current study, we used a combination of 14 microsatellite and two mitochondrial sequence markers to investigate the phylogeography and population structure of I. o. obesulus in South Australia and south-western Victoria, with the aim of identifying any potential evolutionarily significant units and management units relevant to conservation management. Our phylogenetic/population analyses supported the presence of two distinct evolutionary lineages of I. o. obesulus. The first lineage comprised individuals from the Mount Lofty Ranges, Fleurieu Peninsula and Kangaroo Island. A second lineage comprised individuals from the south-east of South Australia and south-western Victoria. We propose that these two lineages represent distinct evolutionarily significant units and should be managed separately for conservation purposes. The findings also raise significant issues for the national conservation status of I. o. obesulus and suggest that the current subspecies classification needs further investigation.

The impact of sheep grazing on the depth of spider burrows and of burrows selected by the pygmy bluetongue lizard (Tiliqua adelaidensis)

2016 ◽  
Vol 43 (8) ◽  
pp. 691 ◽  
Author(s):  
Jessica Clayton ◽  
Michael Bull
Keyword(s):  
Endangered Species ◽  
South Australia ◽  
Sheep Grazing ◽  
Vegetative Cover ◽  
Austral Spring ◽  
Essential Component ◽  
Grazing Sheep ◽  
Essential Resource ◽  
The Impact ◽  
Domestic Stock

Context Grazing by domestic stock can potentially influence ecosystems positively or negatively, depending on the grazing regime and intensity. The pygmy bluetongue lizard (Tiliqua adelaidensis) is an endangered species, restricted to fragmented grasslands in the Mid North region of South Australia, predominantly grazed by sheep. These lizards refuge in vertical burrows. They do not dig their own burrows, instead relying on co-existing spiders for this essential resource. Aims We investigated how sheep grazing influenced spider burrows, and predicted the following: that grazing sheep might trample and destroy shallow burrows; that burrows in grazed habitat with less vegetative cover would have higher temperatures in summer; and that, by way of compensation, spiders would dig deeper burrows in grazed habitat. Methods We monitored 12 30m×30m plots monthly, over two austral spring/summer periods (September–March 2012–14). We recorded the number, depth and occupant of all spider burrows in those plots in each survey. We also measured temperatures inside artificial burrows in grazed and ungrazed habitat over a 3-day period in September 2014. Key results Mean burrow depth increased with grazing. This was not because individual burrows became deeper, but because the shallowest burrows were lost where there were sheep. Burrows were significantly hotter in grazed habitat, but lizards consistently chose deeper, cooler burrows. In the subset of burrows that were occupied by lizards, there was no difference in depth between grazed and ungrazed treatments. We detected no difference in spider digging activity between grazed and ungrazed plots. Conclusions Sheep grazing can destroy shallow burrows, probably through trampling, and because sheep produce burrow filling debris. However, grazing did not affect deeper burrows occupied by pygmy bluetongue lizards. Implications This short study indicated that moderate levels of grazing have low impact on deeper burrows suitable for pygmy bluetongue lizards and for lizard persistence. It explains how sheep and lizards have co-occurred for so long, but leaves open the question of how the loss of shallow burrows affects populations of the burrow-digging spiders that are an essential component of the lizard environment.

Population Dynamics and Movement Patterns of Bolam's Mouse, Pseudomys bolami, at Roxby Downs, South Australia.

1998 ◽  
Vol 20 (3) ◽  
pp. 353
Author(s):  
K.E. Moseby ◽  
J.L. Read
Keyword(s):  
Arid Zone ◽  
Sand Dunes ◽  
South Australia ◽  
Breeding Strategy ◽  
Early Summer ◽  
Ecological Data ◽  
Winter Rainfall ◽  
Land Systems ◽  
Single Night ◽  
Time Of Year

Basic ecological data were collected on Bolam's mouse, Pseudomys bolami, during a six year trapping study at Roxby Downs in northern South Australia. Pseudomys bolami inhabited mixed arid land systems in the Roxby Downs area, sheltering in the longitudinal orange sand dunes but foraging at night principally on the adjacent chenopod swales. Distances of up to 334m were traversed in a single night and recapture rates were high within trapping sessions but low between sessions suggesting wide-ranging movements and short-term residency. Dietary observations imply an omnivorous diet. Whilst the closely related P. hermannsburgensis is regarded as having an opportunistic breeding strategy, P. bolami reproduced opportunistically but also regularly in spring and early summer. Different reproductive strategies may be influenced by the latitudinal distribution of P. bolami near the southern margin of the arid-zone, where rainfall can occur at any time of year but winter rainfall is more predictable. This contrasts with P. hermannsburgensis, which inhabits more northerly arid areas where rainfall is erratic and unpredictable. There was a 10 fold fluctuation in P. bolami captures over the trapping period with numbers of P. bolami and house mice, Mus domesticus peaking 12 months after above average rains during 1992. Rodent captures remained high for two years afterwards. Although P. bolami persisted throughout the study period, M. domesticus was only present when conditions were above average. Trap success of P. bolami or M. domesticus did not vary between the five sub habitats at the 1 ha study site. However, trap success of P. bolami was positively related to vegetation cover, particularly cover of low bluebush, Maireana astrotricha. Maireana astrotricha may be important in providing both food and cover for P. bolami, a scenario consistent with the utilisation of spinifex, Triodia spp. by P. hermannsburgensis in the northern arid-zone. Past over- grazing of chenopod shrublands may have reduced cover and contributed to the suggested decline in the distribution of P. bolami.

scholarly journals Predator recognition and responses in the endangered Macquarie perch (Macquaria australasica)

2015 ◽  
Vol 66 (2) ◽  
pp. 127 ◽  
Author(s):  
Culum Brown ◽  
Jennifer Morgan
Keyword(s):  
Invasive Species ◽  
Endangered Species ◽  
Introduced Species ◽  
Visual Cues ◽  
Chemical Cues ◽  
Conservation Management ◽  
Perca Fluviatilis ◽  
Habitat Destruction ◽  
Perch Perca Fluviatilis ◽  
Threatening Processes

Macquarie perch, Macquaria austalasica, is an endangered species endemic to southern Australia whose distribution is highly fragmented and continues to decline. Key threatening processes include habitat destruction, dams and weirs, overfishing and interactions with introduced species. Here, we examined the responses of small and large Macquarie perch to two native predators and to the introduced redfin perch, Perca fluviatilis. Our results showed that Macquarie perch generally avoided large-bodied native predators but was attracted to small-bodied native predators. Responses to large and small redfin perch lay between these two extremes, suggesting that the Macquarie perch does treat these foreign fish as potential threats. Macquarie perch relied on both visual and chemical cues to identify predators, although its response tended to be stronger when exposed to visual cues. The results suggest that Macquarie perch has the capacity to recognise and respond to invasive species in a threat-sensitive manner, which has positive implications for the conservation management of the species.

Lizard behaviour suggests a new design for artificial burrows

2012 ◽  
Vol 39 (4) ◽  
pp. 295 ◽  
Author(s):  
Mehregan Ebrahimi ◽  
Aaron L. Fenner ◽  
C. Michael Bull
Keyword(s):  
Optimal Design ◽  
Endangered Species ◽  
Surface Activity ◽  
Conservation Management ◽  
Internal Space ◽  
Normal Behaviour ◽  
Natural Behaviour ◽  
Management Interventions ◽  
Occasional Occurrence ◽  
Common Strategy

Context The use of artificial refuges is a common strategy for the conservation management of endangered species. However, artificial refuges may alter an animal’s natural behaviour that in turn may be detrimental to the species. The endangered pygmy bluetongue lizard from Australia is one species that will accept artificial burrows. Aims The aim of the present research was to determine whether the normal behaviour of the pygmy bluetongue lizards differed between artificial and natural burrows, so as to determine whether the existing artificial burrow is an optimal design for this species. Methods In the present study, we filmed the behaviour of lizards as they entered artificial and natural burrows. We compared the number of times a lizard entered a burrow, the time that lizards spent inspecting burrows, and the behaviours that lizards used when entering artificial and natural burrows. Key results We found that in natural burrows, lizards always entered head first, and then usually reversed direction inside, using an enlarged basal chamber, to sit with their head uppermost in the entrance. In artificial burrows, however, lizards had to enter head first, then reverse tail-first back out, and then reverse tail-first back into the burrow (so as to have their head facing upwards) We called this behaviour reversing from outside. Key conclusion The stereotyped reversing-from-outside behaviour when entering artificial burrows, and its occasional occurrence in natural burrows, suggest that it has evolved to allow lizards to use narrow burrows as well as those with a chamber, even though it can increase lizard’s surface activity and exposure to predation. Implication The reversing behaviour from outside the artificial burrow increases exposure to potential predators, and our observations suggest that a re-design of artificial burrows to incorporate internal space for turning around may improve their effectiveness in conservation management interventions.

scholarly journals Taxonomic revision of the threatened African genus Pseudohydrosme Engl. (Araceae), with P. ebo, a new, Critically Endangered species from Ebo, Cameroon

2020 ◽  
Author(s):  
Martin Cheek ◽  
Barthelemy Tchiengue ◽  
Xander van der Burgt
Keyword(s):  
Endangered Species ◽  
Protected Areas ◽  
Type Species ◽  
Conservation Management ◽  
Taxonomic Revision ◽  
Distinct Species ◽  
Critically Endangered ◽  
Critically Endangered Species ◽  
The Usa ◽  
African Genus

ABSTRACTThis is the first revision in nearly 130 years of the African genus Pseudohydrosme, formerly considered endemic to Gabon. Sister to Anchomanes, Pseudohydrosme is distinct from Anchomanes because of its 2–3-locular ovary (not unilocular), peduncle concealed by cataphylls at anthesis and far shorter than the spathe (not exposed, far exceeding the spathe), stipitate fruits and viviparous (vegetatively apomictic) roots (not sessile, roots non-viviparous). Three species, one new to science, are recognised, in two sections. Although doubt has previously been cast on the value of recognising Pseudohydrosme buettneri, of Gabon, it is here accepted and maintained as a distinct species in the monotypic section, Zyganthera. However, it is considered to be probably globally extinct. Pseudohydrosme gabunensis, type species of the genus, also Gabonese, is maintained in Sect. Pseudohydrosme together with Pseudohydrosme ebo sp.nov. of the Ebo Forest, Littoral, Cameroon, the first addition to the genus since the nineteenth century, and which extends the range of the genus 450 km north from Gabon, into the Cross-Sanaga biogeographic area. The discovery of Pseudohydrosme ebo resulted from a series of surveys for conservation management in Cameroon, and triggered this paper. All three species of Pseudohydrosme are morphologically characterised, their habitat and biogeography discussed, and their extinction risks are respectively assessed as Critically Endangered (Possibly Extinct), Endangered and Critically Endangered using the IUCN standard. Clearance of forest habitat for logging, followed by agriculture or urbanisation are major threats. One of the species may occur in a formally protected areas and is also cultivated widely but infrequently in Europe and the USA for its spectacular inflorescences.

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