Landscape and Urban Planning 72 (2005) 265–280 Limitations of using landscape pattern indices to evaluate the ecological consequences of alternative plans and designs Robert C. Corry a,* , Joan Iverson Nassauer b a School of Environmental Design and Rural Development, University of Guelph, Guelph, Ont., Canada N1G 2W1 b School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI 48109-1115, USA Received 11 August 2003; received in revised form 28 January 2004; accepted 15 April 2004 Abstract Landscape pattern indices have been discussed as tools for comparing the ecological consequences of alternative landscape plans and designs. While several landscape ecology investigations have demonstrated the applicability of pattern indices for characterizing landscapes, there is a lack of evidence that pattern indices imply ecological processes. We investigated the utility of landscape pattern indices for judging the habitat implications of alternative landscape plans or designs, and we compared our results to our colleagues’ application of a spatially explicit population (small mammal) habitat model for the same landscape plans. Results of our investigation suggest that planners and designers should be exceedingly cautious in making ecological inferences from landscape pattern index values applied to alternative landscape plans. For our high resolution data representing highly fragmented landscapes, indices were of limited utility in measuring pattern differences, and while reliable, were not valid for measuring differences in an ecological consequence: small mammal habitat. © 2004 Elsevier B.V. All rights reserved. Keywords: Landscape indices; Small mammals; Ecological consequences 1. Introduction The act of planning and designing future land- scapes is a creative endeavour that draws upon scientific knowledge. Each resulting plan or design can be char- acterized as an embodiment of hypotheses about the * Corresponding author. Tel.: +1 519 824 4120x58034; fax: +1 519 767 1686. E-mail address: rcorry@uoguelph.ca (R.C. Corry). effects of landscape change (Nassauer, 1995). Those that plan and design future landscapes rely upon em- pirical evidence, modeling outcomes, and intuition to achieve desired ends and judge among alterna- tives (Laurie, 1975). These approaches can be used to develop more ecologically beneficial landscapes (Ahern, 1991; Opdam et al., 2001). To evaluate and choose among alternative landscape plans, measure- ment of existing landscapes may not be sufficient. Ex- isting landscapes may not be comparable to planned future landscapes, or measuring functions of large ex- isting landscapes may be too costly. Experimentation 0169-2046/$20.00 © 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.landurbplan.2004.04.003