Stream temperatures can index the carrying capacity of redband trout (Oncorhynchus mykiss gairdneri) in basins of the Columbia River Plateau where elevated stream temperatures are anthropogenically induced. Two physiological responses of trout held experimentally at different temperatures were measured :  (1) induction and expression of heat shock protein 70 and (2) whole body lipids.   Based on these findings, habitat quality stream segments was based upon stream temperature signatures: (1) optimal < 18o C, (2) suboptimal 18-21o C, (3) marginal 21.5-23o C and (4) unsuitable 23o C <.   Thermal maps of three tributary basins were reclassified according to these criteria. A hierarchical depiction of the riverscape was used to define sampling strata from remotely sensed imagery: aerial videography, TIR and LiDAR.  Trout distributions (gms*m-2) were visually sampled, corrected for detection bias, in near-continuous spatial sequences. As single variates temperature and availability of Bisson pool types explained 90% and 62% of the variation, respectively of the distribution and abundance of trout and were the two variates that formed the most parsimonious linear models using Akaike Information Criteria. A bioenergetic modification of the Ideal Free Model is now being developed to explain carrying capacity of thermal patches in terms of production.