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-Ecological models for stream fish range in scale from individual fish to entire populations. They have been used to assess habitat quality and to predict the demographic and genetic responses to management or disturbance. In this paper, we conduct the first comprehensive review and synthesis of the vast body of modelling literature on the brown trout, Salmo trutta L., with the aim of developing the framework for a demogenetic model, i.e., a model integrating both population dynamics and genetics. We use a bibliometric literature review to identify two main categories of models: population ecology (including population dynamics and population genetics) and population distribution (including habitat-hydraulic and spatial distribution). We assess how these models have previously been applied to stream fish, particularly brown trout, and how recent models have begun to integrate them to address two key management and conservation questions: (i) How can we predict fish population responses to management intervention? and (ii) How is the genetic structure of fish populations influenced by landscape characteristics? Because salmonid populations tend to show watershed scale variation in both demographic and genetic traits, we propose that models combining demographic, genetic and spatial data are promising tools for improving their management and conservation. We conclude with a framework for an individual-based, spatially explicit demogenetic model that we will apply to stream-dwelling brown trout populations in the near future.

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A multistate capture–recapture model was developed to estimate movements of brown trout ( Salmo trutta ) between a main stem and its headwater tributary and their survival and recapture probabilities in each stream. As all individuals entering or leaving the tributary were captured by trapping, the studied ecological system was fully controlled. The performance of multistate models combining two sources of data (trapping and electrofishing) available for 6 years was first evaluated. Realistic estimates were obtained to infer the average spawning behaviour of trout: (i) 58% returned to their original site after spawning, (ii) 9% returned to their natal site for reproduction, (iii) 55% of the ascending individuals performed natal homing. Because less informative systems are pervading, we eventually assessed the sensitivity of multistate models to the level of trapping data integration. A lack of such data led to an underestimation of movement probabilities, and we found that this effect could be compensated by electrofishing samplings.