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Tornillo Creek, a tributary of the Rio Grande in Texas, United States, has historically been an important nursery and spawning habitat for several native fish species. We examined variation in the seasonal fish assemblages in Tornillo Creek within and between two time periods (1967–1970 vs. 2009–2011), and contemporary fish assemblage–environment associations, in order to understand what environmental factors were associated with seasonal fish abundance and occupancy patterns. Our results indicated that fish assemblages were very different between the two time periods. Contemporary seasonal fish assemblage patterns in Tornillo Creek were less variable than historical assemblages and were linked to several environmental factors including water temperature, stream depth, and current velocity. We suggest that the maintenance of stream flow and connectivity are important for the immigration and emigration of certain riverine fishes in Tornillo Creek and that decreases in stream flow could accelerate the domination of the tolerant species in the creek.


Tornillo Creek, un afluente del rıo Grande en Texas, Estados Unidos, ha sido historicamente un importante criadero y habitat de desove para varias especies de peces nativas. Examinamos la variación en los ensamblajes de peces estacionales en Tornillo Creek dentro y entre dos periodos de tiempo (1967–1970 vs. 2009–2011), y las asociaciones del ensamblaje de peces y el ambiente contemporáneo para entender qué factores ambientales se asociaron con los patrones estacionales de presencia y abundancia de peces. Nuestros resultados indican que los ensamblajes de peces fueron muy diferentes entre los dos periodos de tiempo. Patrones de ensamblaje de peces estacionales contemporáneos en Tornillo Creek fueron menos variables que los ensamblajes hist ´oricos y estuvieron vinculados a varios factores ambientales como la temperatura del agua, profundidad del arroyo y velocidad de la corriente. Sugerimos que el mantenimiento del flujo y la conectividad son importantes para la inmigración y la emigración de ciertos peces fluviales en Tornillo Creek y que las disminuciones en el flujo de corriente podr´ıan acelerar la dominancia de las especies tolerantes en el arroyo.


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Publication Title

The Southwestern Naturalist



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Biology Commons



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