Evaluation of Light as a Non-Physical Cue to Guide Downstream-Migrating Lamprey Transformers Into Traps
The Great Lakes Fishery Commission desires to diversify and integrate sea lamprey control options. Efficient and low-maintenance trapping of downstream migrating transformed sea lampreys would provide an additional control tool. Transformers are sensitive to and respond behaviorally to low-intensity white light (10 lux; Binder et al. 2013), therefore visible white light has potential to repel or guide actively migrating transformers. Light has been shown to be effective in attracting upstream migrant adult sea lamprey into traps in the laboratory (Stamplecoskie et al. 2012) and in guiding (repelling) downstream migrant American and European eels in field applications (EPRI 2001, Versar 2009). The specific effects of wavelength and intensity of light on behavioral response and guidance of transformers are unknown, thus we are proposing this work as an applied proof-of-concept study to determine if broad-spectrum visible (white) light can guide transformers in a stream-like environment. Because water turbidity affects penetration of light through water and hence can reduce potential reaction distance of transformers to a light source, we will conduct tests at varying light intensities to assess the potential reduction of guidance performance by turbidity attenuation of light. We conceptualize that oriented (angled or incremental intensity) light arrays can be designed to function as an effective, low cost/maintenance, non-physical cue to guide transformed sea lampreys into traps. We will determine if: (1) the proportions of transformers guided into traps using (i) parallel or (ii) angled light arrays, mounted (a) above-water or (b) underwater differ from proportions guided to traps during control trials with no lights; and (2) light intensity affects the proportion of transformers guided to the trap.