By Emily Morgan Liljestrand, @fishmodeler
|Emily with a white sucker in her net. Photo: Emily Liljestrand|
My girlfriend’s primary concern was for the safety of the fish.
My biggest worry was getting electrocuted.
We were discussing my plans the following weekend to assist a colleague on an electrofishing trip. Despite the intimidating and dangerous sounding name -- spoiler alert -- no fish were harmed and no humans were shocked! Both of us, it seems, were quite ignorant of what is actually involved in this common fisheries science technique.
As a political scientist, my partner had never even heard of electrofishing, and though I am a fisheries science PhD candidate at Michigan State University, I’m more of an “indoor” researcher. My dissertation project involves re-working stock assessment models of Lake Whitefish. But when my colleague, Josh Hoekwater, asked for my help with his research on resource competition between slimy sculpin and round goby, I jumped at the opportunity to get outside for once.
If Michigan can be approximated using one’s left hand, the Jordan River is approximately at the cuticle of the ring finger. After the 3-hour drive from Lansing, we parked near a bridge overcrossing the river. While I grabbed a hand net, Josh donned his “proton-pack” style backpack electrofishing unit.
|Joshua Hoekwater, doing his best ghostbusters impersonation. Photo: Emily Liljestrand|
The “backpack,” seen in the picture, is connected to a handheld electrofishing wand. When Josh pulled a trigger, the metal ring of the wand would emit a low frequency and nonlethal electric current to stun fish. Reclusive tiny species like the sculpin or goby, which hide under submerged detritus, would float to the surface. That’s when I came in. Net in hand, I would spot the disoriented individuals and scoop them up before the river could carry them downstream. Once we confirmed the fish identity, we could toss them back to their homes to recover and resume their mid-day activities.
Occasionally, when I splashed my hand into the water while the electrofishing unit was active, I could feel the gentle buzzing that the fish were experiencing. Far from the sensation of touching a power outlet, the feeling conjured mental images of eating pop rocks or sitting in a vibrating massage chair. And though Josh’s pack had a heavy, scary-looking industrial battery attached to the bottom, there was a safety mechanism such that if the unit even touched the water, the entire thing would disconnect, eliminating the possibility of electrocution. Ultimately both my and my girlfriend’s worries were unfounded!
|A sculpin netted by the author. Note that the two pelvic fins identify it as a sculpin, and not a round goby. Photo: Emily Liljestrand|
Though Josh and I identified about five of the endangered slimy sculpins that day, no invasive round goby made it into our net (there’s always the chance that one of the few individuals that got away from me may have been the latter). This was a great finding for the environment, but a bad day for Josh. He was hoping to find sections of the river that were only occupied by sculpins, areas only populated by goby, and regions where they coexist. Once he does so, his next step is to strategically place submerged cameras to monitor how they compete for space with the long term goal of better understanding the ecosystem and how to maintain our fisheries.
So, alas, the following Monday found Josh back at the drawing board, revisiting the maps and planning new exploratory outings. And I was back to my desk, my three monitors, and my air conditioning, combing through computer code. But I was happy for the reprieve in the “real world” of fisheries science. Sometimes looking too long at numbers on a screen can make a gal forget what those numbers represent, and I was grateful for the reminder.