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Fish populations rely on complex environmental conditions involving physical, chemical, and biological factors. Understanding the factors that control population persistence and productivity is essential for species management. We assessed the distribution and associated habitat features of a species at risk in Canada, Silver Shiner (Notropis photogenis), within Sixteen Mile Creek, a tributary of Lake Ontario. Using random forest models, we quantified a range of ecological factors (n = 25) to estimate habitat associations for sampled populations and life stages (juvenile, adult). A complex set of ecological factors were informative predictors of Silver Shiner distribution, including physical (stream morphology, water velocity, substrate type), and biological (aquatic and riparian vegetation) conditions. Juveniles were less responsive to habitat conditions but exhibited high seasonal variability in occurrence. Adults were most common in stream sections with greater than 0.5 m depth and stream velocity less than 0.6 m/s, and areas without silt substrate. Broadly, the models predicted Silver Shiner distribution with 68–92% accuracy in non-training data. Our findings describe the habitat conditions that Silver Shiner currently occupies in an urban drainage, which may serve as a point of reference for habitat protection and restoration. Further, predictive species distribution models can serve to identify habitat for further monitoring and restoration. [ABSTRACT FROM AUTHOR]

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Fisheries and Oceans Canada has collected a unique, long‐term data set on the social, biological, and economic dynamics of Canada's recreational fisheries. Starting in 1975, these data were collected through mail surveys to recreational anglers at 5‐year intervals. A longitudinal analysis revealed that there was an average of 4.5 million licensed anglers catching an annual average of 255 million fish. Release rates were relatively high (53% of fish released on average), with recent survey data (2010) suggesting that release rates had exceeded 60%. Recreational anglers also contribute an average of $8.8 billion each year to the Canadian economy. However, recreational angling has become less popular over time, and the average age of participants has increased. The data were also useful for characterizing Canada's fisheries, including species‐specific catch and harvest. Canada is one of the few countries to collect such extensive recreational fisheries data at a national scale and to do so at regular intervals, an approach that could be modeled by other countries. RESUMEN: la agencia de Pesquerías y Océanos de Canadá ha recolectado una base de datos históricos de la dinámica social, biológica y ecológica de las pesquerías recreativas de Canadá. Esta información, que comienza en 1975, fue compilada a través de sondeos por correo postal, realizados a intervalos de cinco años, dirigidos a pescadores. Un análisis longitudinal reveló que existen en promedio 4.5 millones de pescadores con licencia, que capturan una media de 255 millones de peces. Las tasas de liberación fueron relativamente altas (53% de peces liberados) y los datos del sondeo más reciente (2010) indican que la tasa de liberación excede el 60%. Asimismo, los pescadores recreativos contribuyen, en promedio, con $8.8 mil millones anuales a la economía canadiense. Sin embargo, con el tiempo, la pesca recreativa se ha vuelto cada vez menos popular y el promedio de la edad de los participantes se ha incrementado. Los datos también fueron útiles para caracterizar las pesquerías de Canadá, incluyendo captura y cosecha por especie. Canadá es uno de los pocos países que recolectan datos de pesca recreativa de forma tan extensiva a nivel nacional y lo hace en intervalos regulares, algo que pudiera ser imitado por otros países. [ABSTRACT FROM AUTHOR]