Unscreened Water-Diversion Pipes Pose an Entrainment Risk to the Threatened Green Sturgeon, Acipenser medirostris

Mussen, Timothy D.
Cocherell, Dennis
Poletto, Jamilynn B.
Reardon, Jon S.
Hockett, Zachary
Ercan, Ali
Bandeh, Hossein
Kavvas, M. Levent
Cech, Joseph J.
Fangue, Nann A.
Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35 +/- 0.6 cm mean fork length) to entrainment in a large (>500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26-61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation.


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Mussen, Timothy D.; Cocherell, Dennis; Hockett, Zachary; Ercan, Ali; Bandeh, Hossein; Kavvas, M. Levent; Cech, Joseph J.; Fangue, Nann A. (2013-01-01)
Juvenile Chinook Salmon Oncorhynchus tshawytscha from California's Central Valley must pass thousands of unscreened water diversion pipes during their out-migration to the Pacific Ocean. The number of fish that become entrained into (drawn through) these diversions at different hydraulic and environmental conditions is currently unknown. We tested the ability of juvenile Chinook Salmon to avoid entrainment into a 0.46-m-diameter unscreened water diversion pipe while swimming in a large-river-simulation flum...
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The water balance, with large seasonal and annual water level fluctuations, has a critical influence on the nitrogen and phosphorus dynamics of shallow lakes in the semi-arid climate zone. We constructed seasonal water and nutrient budgets for two connected shallow lakes, Lakes Mogan and Eymir, located in Central Anatolia, Turkey. The study period covered 20 years with alternations between dry and wet years as well as restoration efforts including sewage effluent diversion and biomanipulations in Lake Eymir...
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Towards the end of the 1980s, when the spawning grounds in the northwestern shelf (NWS) of the Black Sea were lingering with the effects of eutrophication and of an exotic invasive ctenophore, a series of basin-wide international ichthyoplankton surveys pointed out an increase in the anchovies spawning in the southern half of the Black Sea. Later, with the help of international conservation efforts, several key littoral ecosystem components within the anchovy's historical spawning grounds showed signs of re...
SOYUPAK, S; Gökçay, Celal Ferdi; YERLI, S; ERDEN, S; AKBAY, N; CILESIZ, AF (1994-03-01)
Water quality properties and trophic status of Keban Dam Reservoir have been assessed in detail. The dissolved oxygen contours exhibited somewhat unusual behaviour of temporarily established intermediate layers of low dissolved oxygen concentrations. The phytoplankton species were identified and their composition was evaluated. The reservoir is eutrophic in general terms. However, lotic and limnetic zones of the reservoir have shown different trophic status.
Restoration of the eutrophic Lake Eymir, Turkey, by biomanipulation after a major external nutrient control I
Beklioğlu, Meryem; Tuzun, I (Springer Science and Business Media LLC, 2003-01-01)
Nutrient loading in lakes is recognized as a serious threat to water quality. Over 25 years of raw sewage effluent discharge shifted Lake Eymir from a state dominated by submerged plants to a turbid water state. Successful effluent diversion undertaken in 1995 achieved 88% and 95% reductions in the areal loading of total phosphorus (TP) and dissolved inorganic nitrogen (DIN), respectively. Furthermore, the reduced load of TP was very close to the suggested threshold areal load (0.6 g m(-2) yr(-1)) to attain...
Citation Formats
T. D. Mussen et al., “Unscreened Water-Diversion Pipes Pose an Entrainment Risk to the Threatened Green Sturgeon, Acipenser medirostris,” PLOS ONE, vol. 9, no. 1, pp. 0–0, 2014, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/101050.