Once we had reached our first location, the fish shocker was assembled, and I got my introduction to how the machine works and safety protocols to follow while in the water and the fish shocker active. I was tasked with sweeping a net back and forth along the stream bottom behind the person shocking to catch all the fish. The machine only stuns the fish temporarily so we can collect them in buckets to be inventoried downstream. We did 100 meter intersects in the stream at crossings of concern. Once the intersect was complete, we sat on the stream bank and began counting, measuring, and identifying species. The species we came across in our samples included speckled dace, brown trout, and longfin dace. It was unfortunate to see brown trout, for they are nonnative and outcompete other species, including the species of concern for this area – the loach minnow. Each fish we caught was weighed and the total length (tip of snout to tip of caudal fin) and standard length (tip of snout to caudal peduncle – or base of tail fin) was measured. Total counts for each species were also taken. Once measurements were complete, the fish was released back into the stream.
Many of the fish were in breeding season, so they had developed coloration specific to this time of year and had stunning colors. Brown trout have spots along the side of their body and the ones we caught had incredibly bright coloration that made the spots stand out during breeding. During breeding season it also is not uncommon for some trout species to develop a kype which is when the lower jaw becomes curved in like a hook and is used as a defense against other males and is used in mating hierarchies. The longfin dace that we caught had developed bright red lips and fins, which is indicative of breeding season. The speckled dace also had bright red-orange fins.
While we may not have physically found any loach minnow like we had hoped, all hope is not lost and e-DNA samples will be collected to see if any detections of loach minnow DNA can be found in this stream system. This day was an incredible learning opportunity for me and I am glad I got to experience it.