Remotely sensed agricultural modification improves prediction of suitable habitat for a threatened lizard

ABSTRACT

The geographical distribution of a species is limited by factors such as climate, resources, disturbances and species interactions. Environmental niche models attempt to encapsulate these limits and represent them spatially but do not always incorporate disturbance factors. We constructed MaxEnt models derived from a remotely sensed vegetation classification with, and without, an agricultural modification variable. Including agricultural modification improved model performance and led to more sites with native vegetation and fewer sites with exotic or degraded native vegetation being predicted suitable for A. parapulchella. Analysis of a relatively well-surveyed sub-area indicated that including agricultural modification led to slightly higher omission rates but markedly fewer likely false positives. Expert assessment of the model based on mapped habitat also suggested that including agricultural modification improved predictions. We estimate that agricultural modification has led to the destruction or decline of approximately 30–35% of the most suitable habitat in the sub-area studied and approximately 20–25% of suitable habitat across the entire study area, located in the Australian Capital Territory, Australia. Environmental niche models for a range of species, particularly habitat specialists, are likely to benefit from incorporating agricultural modification. Our findings are therefore relevant to threatened species planning and management, particularly at finer spatial scales.

KEYWORDS:

• MaxEnt
• rare species
• species distribution model
• vegetation type
• human disturbance

Acknowledgements

We thank Mike Austin of CSIRO, Andre Zerger of the Australian Bureau of Meteorology and Margaret Kitchin Environment Planning and Sustainable Development Directorate (EPSDD), ACT Government for advice regarding modelling and for providing data layers. Jennifer Smits (EPSDD), Graeme Hirth (EPSDD) and Mark Dunford (Geoscience Australia) provided additional information about data layers. Rainer Rehwinkel (NSW Office of Environment and Heritage) and Greg Baines (EPSDD) provided the remote-sensing data and helpful information regarding the agricultural modification data. Annabel Smith, Ingrid Stirnemann, Nicole Maron, David Leigh and Percy Wong provided useful comments on the manuscript and we thank the reviewers and Editor for helpful comments which improved the final manuscript as well as the many people who helped to collect data in the field. Finally, we acknowledge the funding received from the ACT Government as well as funding received from the Australian Government in the form of an Australian Postgraduate Award scholarship. This study was authorised by the University of Canberra Committee for Ethics in Animal Experimentation (project authorisation code CEAE08-17). Field work was carried out under license in accordance with the Nature Conservation Act 1980 (Licence no. LT2008311).

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

We acknowledge the funding received from the ACT Government as well as funding received from the Australian Government in the form of an Australian Postgraduate Award scholarship.