Behavioural guidance of Chinook salmon smolts: the variable effects of LED spectral wavelength and strobing frequency

Abstract

We tested Chinook smolt response to combinations of spectra and strobing frequencies emitted from an underwater LED light, designed to guide fish near water diversion infrastructure. Whilst strobing did not alter fish behaviour when compared to constant light, the red light had a repulsive effect during the day, but not at night.

The Right Light: Tiger Salamander Capture Rates and Spectral Sensitivity

“…Increased potential for detection of a light source should increase with an animal's spectral sensitivity (Ford et al 2018), but we found that spectral sensitivity is not necessarily an indicator of attraction to a stimulus (sensu White et al 2005) or a light source (sensu Hansen et al 2018). One external factor that potentially affected visual perception by eastern tiger salamanders is that light transmission in a body of water is influenced by characteristics of the aquatic Table 1.…”

“…Some aquatic animals use phototaxis to move toward light in water (e.g., McConnell et al 2010, Wolf et al 2017), a behavior that potentially evolved to utilize moonlight or starlight for orientation (Thums et al 2016, Cruz et al 2018). Humans have taken advantage of this phototaxis to attract aquatic animals with artificial light during commercial fishing (e.g., teleost fish: Brown 2000, Marchesan et al 2005; cephalopods: Clarke and Pascoe 1998) or repel animals from potentially harmful human infrastructure (e.g., Hansen et al 2018).…”

“…The magnitude of attraction of teleost fish to light sources can vary based on light intensity or color of the lights (Nemeth and Andersen 1992, Marchesan et al 2005, Ford et al 2018, Wei et al 2019). Although many studies have investigated preferences of teleost fish toward light sources, few studies have compared behaviors with variation in intensity and wavelength of these light sources (Marchesan et al 2005, Utne‐Palm et al 2017, Ford et al 2018, Hansen et al 2018). Further, little is known about what light intensities and colors best attract nonfisheries species (but see Cruz et al 2018 for turtles, Poot et al 2008 for migrating birds).…”

Repulsive Effect of Stroboscopic Light Barriers on Native Salmonid (Salmo trutta) and Cyprinid (Pseudochondrostoma duriense and Luciobarbus bocagei) Species of Iberia

“…The difference in repulsive behavior of stroboscopic light, between salmonid and cyprinids is not surprising, since Amaral et al [55] also observed a superior repulsive behavior of salmonid Chinook salmon in relation to the repulsive behavior of the cyprinid Ptychocheilus oregonensis in the Yakima River (USA). Hansen et al [56] verified that Chinook salmon, which exhibited a greater repulsive behavior to various light stimuli in the diurnal period and suggests, in its study, that this result may be related to vision and trophic factors. Nevertheless, our results also display clear behavioral differences between fish species, even inside the same family.…”

Experimental evaluation of the effect of a light-emitting diode device on Chinook salmon smolt entrainment in a simulated river

“…Additionally, differences in light intensity can change the stimulus from being repulsive to attractive (Nemeth & Andersen, 1992) and the required power for this type of lighting is a major implementation cost (Patrick et al, 1985;Brown, 2000;Richards et al, 2007). More recently, therefore, work has begun exploring a range of light frequencies and strobe frequencies of lightemitting diodes (LEDs) for improved performance (Elvidge et al, 2018;Hansen et al, 2018;Ford et al, 2017Ford et al, , 2018.…”