Date of Graduation

Spring 2019


Master of Science in Biology



Committee Chair

Debra S. Finn


Northern Hog Sucker, movement, low-water crossing, longitudinal connectivity, stream fragmentation, Ozark, Missouri, mobile and stationary behavior, radio telemetry

Subject Categories

Aquaculture and Fisheries


Low-water crossings are common in Ozark streams and can restrict longitudinal movement in fishes. I evaluated the impact of the Cedar Grove low-water crossing on Northern Hog Sucker Hypentelium nigricans movement behavior in Missouri’s Current River. Radio-tagged fish upstream (henceforth ‘above’; N = 24) and downstream (henceforth ‘below’; N = 26) of the crossing were followed monthly for a year to assess 1) frequency of fish passage, 2) direction of passage, and 3) maximum displacement of mobile (displacement > 1 km) fish. I then looked at diel movement behavior of stationary (displacement < 1 km) fish near the crossing to assess 1) total displacement and linear home range, 2) direction of diel displacement, and 3) habitat use. Passage was limited to four below-tagged fish and was more likely to occur in the upstream direction and during high flow. The direction of maximum displacement in mobile fish was primarily away from the crossing, and below-tagged fish exhibited over seven times greater displacement than above-tagged fish. Diel displacement and linear home range were greater in above-tagged fish, likely due to degraded upstream habitat that increased the distance between day and night habitats. My results suggest the crossing is a semi-permeable barrier that also affects local-scale movement behavior of Northern Hog Suckers. Alternatives to the low-water crossings at Cedar Grove, such as modifying the side channel into a fish bypass, should be considered to promote natural longitudinal movement of fishes in the upper Current River.


© Jeff Michael Williams

Open Access