Effects of Turbidity on Prey Consumption by Prairie Stream Fishes

Abstract

Reduced suspended‐sediment loads (i.e., turbidity) in many Midwestern prairie rivers have been hypothesized as contributing to the replacement of species that historically occupied highly turbid main‐channel habitats by visually feeding species that are competitively superior in less‐turbid waters. We examined the relationship between prey consumption and turbidity for six fish species from the Canadian River (New Mexico, Oklahoma, and Texas) and found experimental support for this hypothesis. Among species adapted to highly turbid main‐channel habitats, we found that prey consumption by the peppered chub Macrhybopsis tetranema and flathead chub Platygobio gracilis was unaffected (P > 0.12) by elevated turbidity, whereas prey consumption by the Arkansas River shiner Notropis girardi was reduced (P < 0.01). Among species characteristic of less‐turbid habitats, prey consumption by the emerald shiner N. atherinoides, red shiner Cyprinella lutrensis, and sand shiner N. stramineus was reduced (P < 0.01) by elevated turbidity. Compared with prey consumption at 0 nephelometric turbidity units (NTU), prey consumption at 4,000 NTU decreased 21% among peppered chub, 26% among flathead chub, and 59% among Arkansas River shiners, which was less than that observed among emerald (73%), red (84%), and sand shiners (89%). In general, elevated turbidity had less effect on the prey consumption of species that are adapted to highly turbid habitats than on those characteristic of less‐turbid habitats. The high suspended‐sediment loads that historically were characteristic of many prairie streams may have excluded emerald, red, and sand shiners from main‐channel habitats.

Retrospective analysis of fish community change during a half-century of landuse and streamflow changes

“…Changes in stream flow probably are not the only stressor affecting the regional fauna. Decreases in turbidity, to which native species are adapted (Bonner and Wilde 2002), probably have facilitated the replacement of native species by sight-feeding invasive species in regional rivers (Cross and Moss 1987). This decline in turbidity below impoundments can increase predation risk for many minnow species (Rahel and Thel 2004).…”

Longitudinal variation and habitat associations of small fishes in the Bighorn River, Wyoming: influences of river regulation and introduced fishes

“…Moderation of turbidity may be giving the sand shiner a competitive advantage over other native fish species. Bonner and Wilde (2002) found that prey consumption by sand shiners was greatest at moderate turbidity levels, which could explain the success of sand shiner within the Bighorn River study area.…”

Biological assessment of environmental flows for Oklahoma

“…(Mueller and Pyron, 2011). Conditions downstream of reservoirs may provide other benefits to sand shiners, such as decreased turbidity, which has been shown to negatively impact feeding on terrestrial and aquatic insects by this species (Bonner and Wilde, 2002). Suckermouth minnows and slenderhead darters prefer fast flowing waters and require high-velocity areas during spring for spawning (Brewer and others, 2006).…”

“…Several studies have shown changes in fish assemblage structure associated with water resource development and reservoir operations (Bain and others, 1988;Bonner and Wilde, 2002;Marchetti and Moyle, 2001;Perkin and Bonner, 2011). Our analysis examines a temporal sequence of fish assemblage structure in response to reservoir construction in two different stream systems representing different ecological settings.…”