Concurrent Session: Research and monitoring in the Little Plover River watershed: Part 1
9:30 AM - 10:30 AM Thu
CO-AUTHORS: Benjamin Schleppenbach, UW-Stevens Point; Zachary Mohr, UW -Stevens Point; Natalie Coash, UW-Stevens Point; Hal Edwards, UW-Stevens Point
TITLE: Brook trout in the Little Plover River: A system with restoration efforts to improve flow and habitat
ABSTRACT: Brook trout (Salvelinus fontinalis) are popular sportfish, important apex predators, and indicators of cold, high water quality systems. The Little Plover River in Portage County, WI, contains a self-sustaining brook trout population that experienced declines due to extreme low flow periods (2005-2009), including entirely dry river sections. Various groups have conducted restoration efforts in the watershed (e.g., wetlands, well and drainage ditch changes) and channel (e.g., brush bundles) to improve flow and habitat. Our objectives were to determine if brook trout demographics have changed since restoration efforts occurred and if brook trout are using restored habitat including for spawning. Extensive brook trout monitoring commenced in Fall 2015, including sampling with electrofishing to evaluate relative abundance and size structure and to implant passive integrated transponders (PIT) to monitor growth, survival, and movements. In 2020, radio telemetry evaluated brook trout fine-scale movements and use of restored habitat. Weekly redd (spawning ground or “nest”) surveys occurred from 2017 – 2021 to locate spawning locations and were compared to estimates of groundwater input. Preliminary results indicate brook trout abundance and size structure have been stable or increased in restored reaches; a subset of individuals move into upstream restored reaches for spawning; and upstream reaches including restored areas contain higher levels of redds than other reaches. Watershed and in-stream restoration efforts appear to benefit brook trout, however conditions that caused extreme low flows have not occurred since extensive monitoring efforts of this population commenced on the Little Plover River.
BIO: Joshua Raabe is an associate professor of fisheries and water resources at the UW-Stevens Point, where he teaches multiple fisheries courses and introductory labs. He received his PhD from North Carolina State University, a Master’s degree from UW-Stevens Point, and a Bachelor’s degree from Augustana College. His research interests include fish population dynamics, habitat, and movement and migrations.