A Sensory System at the Interface between Urban Stormwater Runoff and Salmon Survival

Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon, United States
Environmental Science and Technology (Impact Factor: 5.33). 05/2007; 41(8):2998-3004. DOI: 10.1021/es062287r
Source: PubMed

ABSTRACT Motor vehicles are a major source of toxic contaminants such as copper, a metal that originates from vehicle exhaust and brake pad wear. Copper and other pollutants are deposited on roads and other impervious surfaces and then transported to aquatic habitats via stormwater runoff. In the western United States, exposure to non-point source pollutants such as copper is an emerging concern for many populations of threatened and endangered Pacific salmon (Oncorhynchus spp.) that spawn and rear in coastal watersheds and estuaries. To address this concern, we used conventional neurophysiological recordings to investigate the impact of ecologically relevant copper exposures (0-20 microg/L for 3 h) on the olfactory system of juvenile coho salmon (O. kisutch). These recordings were combined with computer-assisted video analyses of behavior to evaluate the sensitivity and responsiveness of copper-exposed coho to a chemical predation cue (conspecific alarm pheromone). The sensory physiology and predator avoidance behaviors of juvenile coho were both significantly impaired by copper at concentrations as low as 2 microg/L. Therefore, copper-containing stormwater runoff from urban landscapes has the potential to cause chemosensory deprivation and increased predation mortality in exposed salmon.

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    • "The rhizocephalan may also reduce crab foraging by impairing the ability of crabs to detect prey. Infected crabs took substantially longer than uninfected crabs to react to prey in both our experiments and those of Toscano et al. (2014), which can be indicative of decreased sensory perception (Sandahl et al., 2007). Infections by rhizocephalans are known to damage the nervous system of their hosts as the interna rootlets penetrate the thoracic ganglion and ventral nerve cord (Neilson, 1970). "
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    Journal of Experimental Marine Biology and Ecology 05/2015; 466. DOI:10.1016/j.jembe.2015.02.011 · 1.87 Impact Factor
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    • "Chemical pollutants can impact one or more links in the chain of chemical communication between individual organisms (Brown et al., 1982; Lürling, 2012; Olsén, 2011). Unlike terrestrial animals, fish and aquatic crustaceans possess olfactory and taste receptors that are in direct contact with chemicals in the surrounding fluid medium which can disturb receptor function (Baldwin et al., 2003; Olsén, 2011; Sandahl et al., 2007). Elevated levels of numerous toxicants can impair chemoreception through irreversible physiological damage to receptor cells and organs, and by binding to active sites and preventing signal molecules from being able to reach the binding site (Blinova and Cherkashin, 2012; Tierney et al., 2010). "
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    Ecotoxicology and Environmental Safety 12/2014; 113:369-377. DOI:10.1016/j.ecoenv.2014.12.022 · 2.76 Impact Factor
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    • "learned risky cues across predator taxa (e.g., recognizing unfamiliar predatory congeners as potential threats; Brown et al. 2012). Exposure to other aquatic pollutants such as copper (Cu 2+ ) at sublethal concentrations has also been demonstrated to interfere with chemical alarm signaling (e.g., McPherson et al. 2004; Mirza et al. 2009), albeit through anosmia in the receiver instead of interference with the alarm cues themselves (Sandahl et al. 2007). Salmonids with experimentally induced Cu 2+ -mediated anosmia demonstrated loss of antipredator responses and decreased survival during staged encounters with predators several minutes following Cu 2+ exposure (McIntyre et al. 2012), although it is unclear how long this sensory impairment persists. "
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    Canadian Journal of Fisheries and Aquatic Sciences 05/2014; 71(5). DOI:10.1139/cjfas-2013-0633 · 2.29 Impact Factor
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