Mapping of salmon habitat parameters using airborne imagery and digital ancillary data

The successful integration of air borne remotely sensed imagery and digital ancillary information for the mapping of bottom substrate and channel patt ern as important freshwater habitat parameters for Atlantic salmon was demo nstrated. CASI multispectral image data were collected at wavelengths of 51 0, 590, 660, and 730 nm. Ancillary information consisted of valley gradient and str sam width. Valley gradient was derived from elevation data contain ed in a 1:50,000-scale digital map sheet. Stream width was extracted from t he image data. Separate image classifications were carried out for substrat e type and channel pattern using a hierarchical decision tree algorithm. Th e final overall classification accuracies were 73.76 and 64.47 percent, res pectively. Substrate type and channel pattern were combined to create compo site maps of spawning habitat suitability. The resulting stratification of salmon spawning habitats corresponds well with the findings of earlier inve stigations.