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ii Stock-recruitment parameters for steelhead populations, particularly carrying capacity, can be used to define reference points that signal the need for management changes. To determine the carrying capacity of the Thompson River watershed for steelhead an estimate of potential smolt yield is required. During fall 2001, we evaluated an empirical approach for estimating potential smolt yield and stock productivity. Calibrated nighttime underwater surveys and single-pass electrofishing were used as rapid assessment techniques to estimate total standing stock of steelhead parr (age-1 and age-2). These two methods were calibrated using maximum likelihood (ML) estimates of fish abundance obtained by three-pass electrofishing at a portion of the sample sites. In total, 153 sites were sampled in 20 reach/habitat type strata representing 470 km of juvenile rearing habitat in the Thompson River mainstem and six major tributaries (Coldwater, Spius, Nicola, Deadman, Criss, and Bonaparte). Diver counts and single-pass electrofishing catches were good predictors of ML estimates of parr abundanc