by: Smith-Root Staff on: February 12, 2018
Detecting larval lamprey can be difficult. Smith-Root’s backpack electrofishers are scientifically proven to increase your odds of capturing larval lamprey when using specialized lamprey settings (Dunham et al. 2013).
Juvenile lamprey live in fine sediment. Under typical electrofishing settings, larval lamprey can become immobilized within the sediment, therefore reducing detection capabilities (Thompson et al. 2010).
Specialized lamprey settings provide two channels of electrofishing settings to increase detection and capture capabilities. The primary channel is unique and promotes lamprey movement out of the sediment. A secondary channel, activated by the user by releasing and quickly pressing the anode pole switch, is similar to typical electrofishing settings and aids in capture once the lamprey is out of the sediment.
The Primary Waveform in the lamprey settings consists of a burst of 3 pulses and a short gap every second. The low pulse frequency and short gap of the Primary Waveform allow lamprey to move out of the sediment, whereas the higher frequency and consistent delivery of electricity in the Second Waveform allows the user to capture the ammocoetes with a net.
The LR-24 and Apex backpack electrofishers are the optimal pieces of scientific equipment for capturing larval lamprey. Watch the videos and follow the steps to set up and save the settings now so that you can easily recall these optimal settings in the field.
Enable Dual Channel?option is on screen. Press ENTER.
Primary Pulse Type: Burst of Pulsesoption is on screen. Press ENTER.
Primary Pulses/Burst= 3. Press ENTER.
Primary Burst Frequency= 4 Hz. Press ENTER.
Burst Duty Cycle= 25%. Press ENTER.
Secondary Waveformis displayed.
Secondary Pulse Type: Standard Pulseoption is on screen. Press ENTER.
This one page attachment to Thompson et al. (2010) is an excellent source of information for designing a field study using the Dual Channel Lamprey Settings.
Dunham, J. B., Chelgren, N. D., Heck, M. P., and Clark, S. M. 2013. Comparison of Electrofishing Techniques to Detect Larval Lampreys in Wadeable Streams in the Pacific Northwest. North American Journal of Fisheries Management, 33: 1149–1155. doi:10.1080/02755947.2013.826758
Thompson, K., Brostrom, J. K., Wang Luzier, C. 2010. Best Management Practices to Minimize Adverse Effects to Pacific Lamprey (Entosphenus tridentatus). USDA Forest Service, USDI Fish and Wildlife Service, USDI Bureau of Land Management. 25 pp. ([url=https://www.fws.gov/pacificlamprey/Documents/Best%20Management%20Practices%20for%20Pacific%20Lamprey%20April%202010%20Version.pdf]https://www.fws.gov/pacificlamprey/Documents/Best%20Management%20Practices%20for%20Pacific%20Lamprey%20April%202010%20Version.pdf[/url])