Journal of Arid Environments Journal of Arid Environments 61 (2005) 589–601 The validity and precision of spotlighting for surveying desert mammal communities D.M. Scott a,Ã , S. Waite a , T.M. Maddox b , R.A. Freer c , N. Dunstone c a Biology Division, University of Brighton, Cockcroft Building, Lewes Road Moulsecoomb, Brighton BN2 4GJ, UK b Zoological Society of London, Regents Park, London NW1 4RY, UK c Institute of Ecosystem Science, School of Biological and Biomedical Science, University of Durham, South Road, Durham City DH1 3LE, UK Received 9 December 2003; received in revised form 11 August 2004; accepted 14 September 2004 Available online 2 December 2004 Abstract We investigated the validity of spotlighting techniques for surveying and monitoring desert mammal populations by determining the effect of repeating spotlight transects on the relative precision of density estimates. Precision was modelled by calculating cumulative mean density and associated coefficient of variation. The effect of moonlight at the time of surveying was also investigated. The results show that spotlighting is a valid technique for monitoring some species, however the number of transects required to obtain pre-defined adequate levels of precision is species-dependent. Reasons for these findings are discussed and recommendations for future spotlight surveys for monitoring desert mammal populations are given. r 2004 Elsevier Ltd. All rights reserved. Keywords: Density; Fox; Hare; Jerboa; Jordan; Precision; Spotlighting; Strip-transect ARTICLE IN PRESS www.elsevier.com/locate/jnlabr/yjare 0140-1963/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.jaridenv.2004.09.008 Ã Corresponding author. E-mail address: dawn.scott@brighton.ac.uk (D.M. Scott).