Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

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

Jessica Clayton A B and Michael Bull A
+ Author Affiliations
- Author Affiliations

A School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia.

B Corresponding author. Email: jessica.clayton@flinders.edu.au

Wildlife Research 43(8) 691-703 https://doi.org/10.1071/WR16138
Submitted: 25 July 2016  Accepted: 27 November 2016   Published: 3 March 2017

Abstract

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 30 m × 30 m 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.

Additional keywords: burrow, grassland grazing, pygmy bluetongue lizard, spider.


References

Agha, M., Delaney, D., Lovich, J. E., Briggs, J., Austin, M., and Price, S. J. (2015). Nelson’s big horn sheep (Ovis canadensis nelsoni) trample Agassiz’s desert tortoise (Gopherus agassizii) burrow at a California wind energy facility. Bulletin of the Southern California Academy of Sciences 114, 58–62.

Augustine, D. J., and Frank, D. A. (2001). Effects of migratory grazers on spatial heterogeneity of soil nitrogen properties in a grassland ecosystem. Ecology 82, 3149–3162.

Augustine, D. J., and McNaughton, S. J. (2007). Interactive effects of ungulate herbivores, soil fertility and variable rainfall on ecosystem processes in a semi-arid savanna. Ecosystems 9, 1242–1256.
Interactive effects of ungulate herbivores, soil fertility and variable rainfall on ecosystem processes in a semi-arid savanna.Crossref | GoogleScholarGoogle Scholar |

Blaum, N., Rossmanith, E., Fleissner, G., and Jeltsch, F. (2007). The conflicting importance of shrubby landscape structures for the reproductive success of the yellow mongoose (Cynictis penicillata). Journal of Mammalogy 88, 194–200.
The conflicting importance of shrubby landscape structures for the reproductive success of the yellow mongoose (Cynictis penicillata).Crossref | GoogleScholarGoogle Scholar |

Brits, J., Van Rooyen, M. W., and Van Rooyen, N. (2002). Ecological impact of large herbivores on the woody vegetation at selected watering points on the eastern basaltic soils in the Kruger National Park. African Journal of Ecology 40, 53–60.
Ecological impact of large herbivores on the woody vegetation at selected watering points on the eastern basaltic soils in the Kruger National Park.Crossref | GoogleScholarGoogle Scholar |

Bull, C. M., Godfrey, S. S., Ebrahimi, M., and Fenner, A. L. (2015). Long and short term residence in refuge burrows by endangered pygmy bluetongue lizards. Amphibia-Reptilia 36, 119–124.
Long and short term residence in refuge burrows by endangered pygmy bluetongue lizards.Crossref | GoogleScholarGoogle Scholar |

Bureau of Meteorology (2014). Climate data online: rainfall data for Burra community school. Available at http://www.bom.gov.au.

Churchill, T., and Ludwig, J. (2004). Changes in spider assemblages along grassland and savanna grazing gradients in northern Australia. The Rangeland Journal 26, 3–16.
Changes in spider assemblages along grassland and savanna grazing gradients in northern Australia.Crossref | GoogleScholarGoogle Scholar |

Clayton, J., and Bull, C. M. (2015). The impact of sheep grazing on burrows for pygmy bluetongue lizards and on burrow digging spiders. Journal of Zoology 297, 44–53.
The impact of sheep grazing on burrows for pygmy bluetongue lizards and on burrow digging spiders.Crossref | GoogleScholarGoogle Scholar |

Cocroft, R. B., and Hambler, K. (1989). Observations on a commensal relationship of the microhylid frog Chiasmocleis ventrimaculata and the burrowing theraphosid spider Xenesthis immanis in southeastern Peru. Biotropica 21, 2–8.
Observations on a commensal relationship of the microhylid frog Chiasmocleis ventrimaculata and the burrowing theraphosid spider Xenesthis immanis in southeastern Peru.Crossref | GoogleScholarGoogle Scholar |

Dechant, J. A., Sondreal, M. L., Johnson, D. H., Igl, L. D., Goldade, C. M., Rabie, P. A., and Euliss, B. R. (2002). Effects of management practices on grassland birds: Burrowing Owl. USGS Northern Prairie Wildlife Research Center Paper 123. (Wildlife Damage Management: Stevens Point.)

Dennis, P., Young, M. R., and Gordon, I. J. (1998). Distribution and abundance of small insects and arachnids in relation to structural heterogeneity of grazed, indigenous grasslands. Ecological Entomology 23, 253–264.
Distribution and abundance of small insects and arachnids in relation to structural heterogeneity of grazed, indigenous grasslands.Crossref | GoogleScholarGoogle Scholar |

Ebrahimi, M., and Bull, C. (2012). Food supplementation reduces post-release dispersal during simulated translocation of the endangered pygmy bluetongue lizard Tiliqua adelaidensis. Endangered Species Research 18, 169–178.
Food supplementation reduces post-release dispersal during simulated translocation of the endangered pygmy bluetongue lizard Tiliqua adelaidensis.Crossref | GoogleScholarGoogle Scholar |

Ebrahimi, M., and Bull, C. M. (2015). Behavioural changes in an endangered grassland lizard resulting from simulated agricultural activities. Journal of Arid Environments 113, 102–107.
Behavioural changes in an endangered grassland lizard resulting from simulated agricultural activities.Crossref | GoogleScholarGoogle Scholar |

Ebrahimi, M., Schofield, J. A., and Bull, C. M. (2012). Getting your feet wet: responses of the endangered pygmy bluetongue lizard (Tiliqua adelaidensis) to rain induced burrow flooding. Herpetology Notes 5, 297–301.

Fellows, H. L., Fenner, A. L., and Bull, C. M. (2009). Spiders provide important resources for an endangered lizard. Journal of Zoology 279, 156–163.
Spiders provide important resources for an endangered lizard.Crossref | GoogleScholarGoogle Scholar |

Fenner, A. L., Schofield, J. A., Smith, A., and Bull, C. M. (2008). Observations of snake predation on the pygmy bluetongue lizard, Tiliqua adelaidensis. Herpetofauna 38, 105–109.

Fleischner, T. L. (1994). Ecological costs of livestock grazing in western North America. Conservation Biology 8, 629–644.
Ecological costs of livestock grazing in western North America.Crossref | GoogleScholarGoogle Scholar |

Foley, J. A., DeFries, R., Asner, G. P., Barford, C., Bonan, G., Carpenter, S. R., Chapin, F. S., Coe, M. T., Daily, G. C., Gibbs, H. K., Helkowski, J. H., Holloway, T., Howard, E. A., Kucharik, C. J., Monfreda, C., Patz, J. A., Prentice, I. C., Ramankutty, N., and Snyder, P. K. (2005). Global consequences of land use. Science 309, 570–574.
Global consequences of land use.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXmsFChtrs%3D&md5=af85f8790269293b4b0d26b9ff79c266CAS |

Gardiner, T., and Hassall, M. (2008). Does microclimate affect grasshopper populations after cutting of hay in improved grassland? Journal of Insect Conservation 13, 97–102.
Does microclimate affect grasshopper populations after cutting of hay in improved grassland?Crossref | GoogleScholarGoogle Scholar |

Grandmaison, D. D., Ingraldi, M. F., and Peck, F. R. (2010). Desert tortoise microhabitat selection on the Florence Military Reservation, South-Central Arizona. Journal of Herpetology 44, 581–590.
Desert tortoise microhabitat selection on the Florence Military Reservation, South-Central Arizona.Crossref | GoogleScholarGoogle Scholar |

Greene, R. S. B., Kinnell, P. I. A., and Wood, J. T. (1994). Role of plant cover and stock trampling on runoff and soil-erosion from semi-arid wooded rangelands. Australian Journal of Soil Research 32, 953–973.

Hendricks, H. H., Bond, W. J., Midgley, J. J., and Novellie, P. A. (2005). Plant species richness and composition along livestock grazing intensity gradients in a Namaqualand (South Africa) protected area. Plant Ecology 176, 19–33.
Plant species richness and composition along livestock grazing intensity gradients in a Namaqualand (South Africa) protected area.Crossref | GoogleScholarGoogle Scholar |

Holmes, A. L., Green, G. A., Morgan, R. L., and Livezey, K. B. (2003). Burrowing owl nest success and burrow longevity in North Central Oregon. Western North American Naturalist 63, 244–250.

Hutchinson, M., Milne, T., and Croft, T. (1994). Redescription and ecological notes on the pygmy bluetongue, Tiliqua adelaidensis (Squamata : Scincidae). Transactions of the Royal Society of South Australia 118, 217–226.

Hyde, M. K. (1995). The temperate grasslands of South Australia: their composition and conservation status. World Wide Fund For Nature, Sydney, Australia.

Jones, K. B. (1981). Effects of grazing on lizard abundance and diversity in western Arizona. The Southwestern Naturalist 26, 107–115.
Effects of grazing on lizard abundance and diversity in western Arizona.Crossref | GoogleScholarGoogle Scholar |

Jones, C. A., and Franz, R. (1990). Use of gopher tortoise burrows by Florida mice (Podomys floridanus) in Putnam County, Florida. Florida Field Naturalist 18, 45–51.

Ke, D., and Lu, X. (2009). Burrow use by Tibetan ground tits Pseudopodoces humilis: coping with life at high altitudes. The Ibis 151, 321–331.
Burrow use by Tibetan ground tits Pseudopodoces humilis: coping with life at high altitudes.Crossref | GoogleScholarGoogle Scholar |

Kearney, M., Shine, R., and Porter, W. P. (2009). The potential for behavioural thermoregulation to buffer ‘cold blooded’ animals against climate warming. Proceedings of the National Academy of Sciences of the United States of America 106, 3835–3840.
The potential for behavioural thermoregulation to buffer ‘cold blooded’ animals against climate warming.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjt1GksLc%3D&md5=dd28fa61956aa2e82f7ff1b112965d57CAS |

Kovac, K. J., and Mackay, D. A. (2007). An experimental study of the impacts of cattle on spider communities of artesian springs in South Australia. Journal of Insect Conservation 13, 57–65.
An experimental study of the impacts of cattle on spider communities of artesian springs in South Australia.Crossref | GoogleScholarGoogle Scholar |

Lewis, T., Clark, P. J., Reid, N., and Whalley, R. D. (2008). Perennial grassland dynamics on fertile plains: is coexistence mediated by disturbance? Austral Ecology 33, 128–139.
Perennial grassland dynamics on fertile plains: is coexistence mediated by disturbance?Crossref | GoogleScholarGoogle Scholar |

Lobry de Bruyn, L., and Kingston, T. (1997). Effects of summer irrigation and trampling in dairy pastures on soil physical properties and earthworm number and species composition. Australian Journal of Agricultural Research 48, 1059–1079.
Effects of summer irrigation and trampling in dairy pastures on soil physical properties and earthworm number and species composition.Crossref | GoogleScholarGoogle Scholar |

Loe, L. E., Mysterud, A., Stien, A., Steen, H., Evans, D. M., and Austrheim, G. (2007). Positive short-term effects of sheep grazing on the alpine avifauna. Biology Letters 3, 110–112.
Positive short-term effects of sheep grazing on the alpine avifauna.Crossref | GoogleScholarGoogle Scholar |

Macchi, L., and Grau, H. R. (2012). Piospheres in the dry Chaco. Contrasting effects of livestock puestos on forest vegetation and bird communities. Journal of Arid Environments 87, 176–187.
Piospheres in the dry Chaco. Contrasting effects of livestock puestos on forest vegetation and bird communities.Crossref | GoogleScholarGoogle Scholar |

McGinnis, S. M., and Voigt, W. G. (1971). Thermoregulation in the desert tortoise, Gopherus agassizii. Comparative Biochemistry and Physiology. Part A, Physiology 40, 119–126.
Thermoregulation in the desert tortoise, Gopherus agassizii.Crossref | GoogleScholarGoogle Scholar |

Milne, T. (1999). Conservation and ecology of the endangered pygmy bluetongue lizard Tiliqua adelaidensis. Ph.D. Thesis, Flinders University, SA.

Milne, T., and Bull, C. M. (2000). Burrow choice by individuals of different sizes in the endangered pygmy bluetongue lizard Tiliqua adelaidensis. Biological Conservation 95, 295–301.
Burrow choice by individuals of different sizes in the endangered pygmy bluetongue lizard Tiliqua adelaidensis.Crossref | GoogleScholarGoogle Scholar |

Milne, T., Bull, C. M., and Hutchinson, M. N. (2003). Use of burrows by the endangered pygmy bluetongue lizard, Tiliqua adelaidensis (Scincidae). Wildlife Research 30, 523–528.
Use of burrows by the endangered pygmy bluetongue lizard, Tiliqua adelaidensis (Scincidae).Crossref | GoogleScholarGoogle Scholar |

Mohr, D., Cohnstaedt, L. W., and Topp, W. (2005). Wild boar and red deer affect soil nutrients and soil biota in steep oak stands of the Eifel. Soil Biology & Biochemistry 37, 693–700.
Wild boar and red deer affect soil nutrients and soil biota in steep oak stands of the Eifel.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXmvFyhtA%3D%3D&md5=fb7af950150cd877c719720603c562d3CAS |

Mulholland, B., and Fullen, M. A. (1991). Cattle trampling and soil compaction on loamy sands. Soil Use and Management 7, 189–193.
Cattle trampling and soil compaction on loamy sands.Crossref | GoogleScholarGoogle Scholar |

Mwendera, E. J., Saleem, M. A. M., and Woldu, Z. (1997). Vegetation response to cattle grazing in the Ethiopian highlands. Agriculture, Ecosystems & Environment 64, 43–51.
Vegetation response to cattle grazing in the Ethiopian highlands.Crossref | GoogleScholarGoogle Scholar |

Pavey, C. R., Burwell, C. J., and Nano, C. E. M. (2010). Foraging ecology and habitat use of Slater’s skink (Egernia slateri): an endangered Australian desert lizard. Journal of Herpetology 44, 563–571.
Foraging ecology and habitat use of Slater’s skink (Egernia slateri): an endangered Australian desert lizard.Crossref | GoogleScholarGoogle Scholar |

Pettigrew, M., and Bull, C. M. (2011). The impact of heavy grazing on burrow choice in the pygmy bluetongue lizard, Tiliqua adelaidensis. Wildlife Research 38, 299–306.
The impact of heavy grazing on burrow choice in the pygmy bluetongue lizard, Tiliqua adelaidensis.Crossref | GoogleScholarGoogle Scholar |

Pettigrew, M., and Bull, C. M. (2012). The response of pygmy bluetongue lizards to simulated grazing in the field during three drought years. Wildlife Research 39, 540–545.
The response of pygmy bluetongue lizards to simulated grazing in the field during three drought years.Crossref | GoogleScholarGoogle Scholar |

Pettigrew, M., and Bull, C. M. (2014). Prey capture behaviour by pygmy bluetongue lizards with simulated grazing. New Zealand Journal of Ecology 38, 45–52.

Pianka, E. R. (2013). Notes on the ecology and natural history of the rarely recorded gekkonid lizard Heteronotia binoei in the Great Victoria desert of Western Australia. Western Australian Naturalist (Perth) 29, 120–125.

Pike, D. A., and Mitchell, J. C. (2013). Burrow-dwelling ecosystem engineers provide thermal refugia throughout the landscape. Animal Conservation 16, 694–703.
Burrow-dwelling ecosystem engineers provide thermal refugia throughout the landscape.Crossref | GoogleScholarGoogle Scholar |

Pucheta, E., Cabido, M., Diaz, S., and Funes, G. (1998). Floristic composition, biomass and aboveground net plant production in grazed and protected sites in a mountain grassland of central Argentina. Acta Oecologica 19, 97–105.
Floristic composition, biomass and aboveground net plant production in grazed and protected sites in a mountain grassland of central Argentina.Crossref | GoogleScholarGoogle Scholar |

Read, J. L., and Cunningham, R. (2010). Relative impacts of cattle grazing and feral animals on an Australian arid zone reptile and small mammal assemblage. Austral Ecology 35, 314–324.
Relative impacts of cattle grazing and feral animals on an Australian arid zone reptile and small mammal assemblage.Crossref | GoogleScholarGoogle Scholar |

Read, J., Carter, J., Moseby, K., and Greenville, A. (2008). Ecological roles of rabbit, bettong and bilby warrens in arid Australia. Journal of Arid Environments 72, 2124–2130.
Ecological roles of rabbit, bettong and bilby warrens in arid Australia.Crossref | GoogleScholarGoogle Scholar |

Reeder, J. D., and Schuman, G. E. (2002). Influence of livestock grazing on C sequestration in semi-arid mixed-grass and short-grass rangelands. Environmental Pollution 116, 457–463.
Influence of livestock grazing on C sequestration in semi-arid mixed-grass and short-grass rangelands.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXovVertrc%3D&md5=d81d5446dac04f16d2f5e2ae1635f4b5CAS |

Roper, T., Bennett, N., Conradt, L., and Molteno, A. (2001). Environmental conditions in burrows of two species of African mole-rat, Georhychus capensis and Cryptomys damarensis. Journal of Zoology 254, 101–107.
Environmental conditions in burrows of two species of African mole-rat, Georhychus capensis and Cryptomys damarensis.Crossref | GoogleScholarGoogle Scholar |

Rothermel, B. B., and Luhring, T. M. (2005). Burrow availability and dessication risk of mole salamanders (Ambystoma talpoideum) in harvested versus unharvested forest stands. Journal of Herpetology 39, 619–626.
Burrow availability and dessication risk of mole salamanders (Ambystoma talpoideum) in harvested versus unharvested forest stands.Crossref | GoogleScholarGoogle Scholar |

Singer, F. J., and Schoenecker, K. A. (2003). Do ungulates accelerate or decelerate nitrogen cycling? Forest Ecology and Management 181, 189–204.
Do ungulates accelerate or decelerate nitrogen cycling?Crossref | GoogleScholarGoogle Scholar |

Singleton, P. L., and Addison, B. (1999). Effects of cattle treading on physical properties of three soils used for dairy farming in the Waikato, North Island, New Zealand. Soil Research 37, 891–902.
Effects of cattle treading on physical properties of three soils used for dairy farming in the Waikato, North Island, New Zealand.Crossref | GoogleScholarGoogle Scholar |

Smith, A. T., and Foggin, J. M. (1999). The plateau pika (Ochotona curzoniae) is a keystone species for biodiversity on the Tibetan plateau. Animal Conservation 2, 235–240.
The plateau pika (Ochotona curzoniae) is a keystone species for biodiversity on the Tibetan plateau.Crossref | GoogleScholarGoogle Scholar |

Souter, N. J., and Milne, T. (2009). Grazing exclusion as a conservation measure in a South Australian temperate native grassland. Grassland Science 58, 76–84.

Souter, N. J., Bull, C. M., and Hutchinson, M. N. (2004). Adding burrows to enhance a population of the endangered pygmy bluetongue lizard, Tiliqua adelaidensis. Biological Conservation 116, 403–408.
Adding burrows to enhance a population of the endangered pygmy bluetongue lizard, Tiliqua adelaidensis.Crossref | GoogleScholarGoogle Scholar |

Souter, N. J., Bull, C. M., Lethbridge, M. R., and Hutchinson, M. N. (2007). Habitat requirements of the endangered pygmy bluetongue lizard, Tiliqua adelaidensis. Biological Conservation 135, 33–45.
Habitat requirements of the endangered pygmy bluetongue lizard, Tiliqua adelaidensis.Crossref | GoogleScholarGoogle Scholar |

Stevens, T. A., Evans, M. C., Osborne, W. S., and Sarre, S. D. (2010). Home ranges of, and habitat use by, the grassland earless dragon (Tympanocryptis pinguicolla) in remnant native grasslands near Canberra. Australian Journal of Zoology 58, 76–84.
Home ranges of, and habitat use by, the grassland earless dragon (Tympanocryptis pinguicolla) in remnant native grasslands near Canberra.Crossref | GoogleScholarGoogle Scholar |

Teague, W. R., Dowhower, S. L., Baker, S. A., Haile, N., DeLaune, P. B., and Conover, D. M. (2011). Grazing management impacts on vegetation, soil biota and soil chemical, physical and hydrological properties in tall grass prairie. Agriculture, Ecosystems & Environment 141, 310–322.
Grazing management impacts on vegetation, soil biota and soil chemical, physical and hydrological properties in tall grass prairie.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXntlGnt7Y%3D&md5=15abda8c760879a0d554368b75b4dbfaCAS |

Torre, I., Diaz, M., Martinez-Padilla, J., Bonal, R., Vinuela, J., and Fargallo, J. A. (2007). Cattle grazing, raptor abundance and small mammal communities in Mediterranean grasslands. Basic and Applied Ecology 8, 565–575.
Cattle grazing, raptor abundance and small mammal communities in Mediterranean grasslands.Crossref | GoogleScholarGoogle Scholar |

Tracy, F. B., and Frank, A. D. (1998). Herbivore influence on soil microbial biomass and nitrogen mineralization in a northern grassland ecosystem: Yellowstone National Park. Oecologia 114, 556–562.
Herbivore influence on soil microbial biomass and nitrogen mineralization in a northern grassland ecosystem: Yellowstone National Park.Crossref | GoogleScholarGoogle Scholar |

Turner, G. S. (2014). Burrow-use by herpetofauna of the Werribee-Keilor plains. Victorian Naturalist 131, 72–83.

Uresk, D. W., MacCracken, J. G., and Bjugstad, A. J. (1981). Prairie dog density and cattle grazing relationships. In ‘Great Plains Wildlife Damage Control Workshop Proceedings’. Paper 145, 199–201. (University of Nebraska–Lincoln: NE).

Vulliamy, B., Potts, S. G., and Willmer, P. G. (2006). The effects of cattle grazing on plant-pollinator communities in a fragmented Mediterranean landscape. Oikos 114, 529–543.
The effects of cattle grazing on plant-pollinator communities in a fragmented Mediterranean landscape.Crossref | GoogleScholarGoogle Scholar |

Whitman, W. C. (1974). Influence of grazing on the microclimate of mixed grass prairie. In ‘Plant Morphogenesis as the Basis for Scientific Management of Range Resources’. (Eds K. M. Kreitlow, R. H. Hart.) pp. 2017–218. (USDA: Washington, DC.)

Williams, K., and Cary, J. (2001). Perception of native grassland in southeastern Australia. Ecological Management & Restoration 2, 139–144.
Perception of native grassland in southeastern Australia.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BD3MnptVSgtQ%3D%3D&md5=fd769f1a8c4310c5630f31a2ce1cca29CAS |

Zimmerman, L. C., O’Connor, M. P., Bulova, S. J., Spotila, J. R., Kemp, S. J., and Salice, C. J. (1994). Thermal ecology of desert tortoises in the eastern Mojave Desert: seasonal patterns of operative and body temperatures and microhabitat utilization. Herpetological Monograph 8, 45–59.
Thermal ecology of desert tortoises in the eastern Mojave Desert: seasonal patterns of operative and body temperatures and microhabitat utilization.Crossref | GoogleScholarGoogle Scholar |