New technique describing spatial scaling and habitat selection in riverine habitats

Abstract

ABSTRACTWe propose a quantitative multi-scale technique based on frequency analysis and randomisation to study habitatselection by fish in riverine habitats. The technique can be used over any range of spatial scales in an environmentwith irregular boundaries. We illustrate the approach using simulated distributions and field data on juvenile Atlanticsalmon ( Salmo salar ) distributions, obtained by snorkelling in North Harbour River, Newfoundland, Canada. Wesuggest that current habitat models may be improved by a more explicit use of space and time scales. Multi-scaleapproaches to study fish–habitat relationships and multi-scale habitat models may be better at capturing how fish areassociated with their environment than single-scale approaches and models. Habitat selection studies should focus onidentifying scales most appropriate to management questions. From this, management of fish populations and fishhabitats may be improved. © 1998 John Wiley & Sons, Ltd. KEY WORDS : scale; spatial pattern; patchiness; heterogeneity; point pattern; habitat selection; habitat modelling; habitat assess-ment