Midwest Fish & Wildlife Conference 2016

AUTHORS: Seth Love*, Southeast Missouri State University; Sara Tripp, Missouri Department of Conservation; Quinton Phelps, Missouri Department of Conservation

ABSTRACT: Smallmouth buffalo Ictiobus bubalus are a commercially harvested warmwater fish species found within many Midwestern rivers and lakes; however, minimal scientific information exists. The objectives of this study were to assess historic commercial harvest data, determine current demographics, and evaluate the sustainability of the smallmouth buffalo population. To carry out this study, we evaluated existing commercial harvest data collected by the Missouri Department of Conservation. In order to acquire baseline population demographic data on this commercially important fish species, we collected data (e.g., length and age) from 113 specimens caught within the Middle Mississippi River. Overall, trends in buffalofish commercial harvest data ranged from 8.36 to 129.19 t/year between 1945-2015. In terms of demographics, we collected a broad size distribution with total lengths between 250 and 801 mm (M = 622.3, SE = 7.22) and lapilli otolith age estimates ranged from 5 to 39 years old (M = 19.0, SE = 0.686). Using age information, total annual mortality was estimated at 10.1%. Furthermore, our simulation modeling suggests that the smallmouth buffalo population is sustainable under the current low levels of commercial harvest. To this end, baseline knowledge generated during this study has provided potential insight into managing this commercially important species in the Middle Mississippi River.

AUTHORS: Joseph D. Thiessen*, Department of Biology, University of Nebraska at Kearney; Keith Koupal, Nebraska Game and Parks Commission; Casey Schoenebeck, Department of Biology, University of Nebraska at Kearney

ABSTRACT: The Plains topminnow Fundulus sciadicus is an endemic Great Plains stream fish that appears to be experiencing reductions in range and abundance, resulting in regional protection and federal listing considerations. In response, Nebraska Natural Legacy Project, Nebraska Game and Parks Commission, and the University of Nebraska at Kearney have proactively begun translocation efforts to reestablish and augment populations throughout the state. Project focus is to assess the long-term persistence of previously reestablished populations and determine the short-term success of semi-regular augmentation efforts. Assessments were completed on 17 stocking locations in 2011, concluding that only 47% (8 sites) showed short-term persistence. Unsuccessfully deemed sites (9 sites) had additional augmentation stocking events conducted in fall of 2014 at a rate of 2500 fish/habitat acre. All sites were revisited in 2015 to assess both the 8 successful sites for long-term persistence and determine short-term success on the 9 augmented sites. Translocation persistence will be determined using probability analysis, which includes species presence, available habitat, and biotic assemblage structure. Results will aid in the development of a state wide management tool for application in future translocation efforts of Plains topminnow.

AUTHORS: Jason A. DeBoer, Andrea K. Fritts, Mark W. Fritts, Richard M. Pendleton, Levi E. Solomon, T.D. VanMiddlesworth, and Andrew F. Casper Illinois River Biological Station, Illinois Natural History Survey, Prairie Research Institute, University of Illinois-Urbana Champaign

ABSTRACT: Understanding how a fish’s environment affects life-history expression throughout its geographic range is important for effectively managing and conserving important resources. Largemouth bass, black crappie, and bluegill are popular sportfish in the Midwest, making their management and conservation a priority for many natural resource agencies. We collected largemouth bass, black crappie, and bluegill from three distinct habitats in the Illinois River Watershed – the Upper Illinois River/Lower Des Plaines River, LaGrange reach of the Lower Illinois River, and The Nature Conservancy’s Emiquon Preserve, a large restored floodplain wetland – during Spring 2015 to better understand the effect of environmental differences on sportfish life-history expression. These habitats vary in many aspects, including location, contaminant load, bathymetry, water turbidity, and macrophyte abundance. We weighed and measured fishes, categorized visible parasite presence or absence, and extracted otoliths (to estimate fish age), gonads (to determine sex, estimate fecundity, and calculate GSI), and livers (to calculate HSI). Many life-history traits differed among habitats, though the results were often sex- and species-specific; the most-dramatic differences were in ovary weight-somatic weight relationships. Environmental factors appear to affect fish life-history expression, but more research is needed on additional factors involved (e.g., biotic interactions) and the mechanisms of effect. We suggest that management and conservation of these fishes in different habitat types and locations needs to consider life-history expression for these important sportfish.

AUTHORS: Cameron W. Goble, Michigan Technological University; Nancy A. Auer, Michigan Technological University; Casey J. Huckins, Michigan Technological University; Brian M. Danhoff, Michigan Technological University; J. Marty Holtgren, Michigan Department of Natural Resources; Stephanie A. Ogren, Little River Band of Ottawa Indians

ABSTRACT: We conducted a three year investigation of fish community and habitat in eight tributary streams of the Manistee River, MI ranging in average width from 1.7 – 8.5 m to explore their suitability as potential locations for reestablishing Arctic grayling Thymallus arcticus, an extirpated native species, in the State of Michigan. The effects of biotic and abiotic factors on the relative abundance, density, and biomass of brook trout Salvelinus fontinalis, brown trout Salmo trutta and slimy sculpin Cottus cognatus were evaluated at 22 tributary study sites. Together these species comprised 94% of all fish captured over the course of the study and are commonly used as indicator species for assessing cold-water stream systems in the Great Lakes region. Catch per unit effort (CPUE) of brown trout was negatively correlated with CPUE of both brook trout and slimy sculpin. Instream habitat features also play roles in structuring the fish community in these streams. For example, both brown trout CPUE and biomass tended to increase with stream width, depth, and velocity whereas brook trout CPUE and biomass tended to be greatest in smaller streams (< 2.5m wide) and slimy sculpin densities were negatively correlated with stream width and velocity. It appears that stream size is an important factor in some of the observed differences in abundance, density, and biomass for three of the most abundant cold-water fish species in this portion of the Manistee River watershed. Possible differences in catchability between species as related to stream size could explain why direct negative correlations between species were observed for CPUE but not for density or biomass.

AUTHORS: David Coulter, Department of Forestry and Natural Resources, Purdue University; James Breck, Institute for Fisheries Research, Michigan Department of Natural Resources, School of Natural Resources and Environment, University of Michigan; Cary Troy, School of Civil Engineering, Purdue University; Maria Sepúlveda, Department of Forestry and Natural Resources, Purdue University; Tomas O. Höök, Department of Forestry and Natural Resources, Purdue University

ABSTRACT: Warm water discharges are a common component of many waterways that create thermally dynamic environments across both space and time. Such thermal variability has potentially strong influence on the physiology, ecological interactions, and population trajectories of fishes. The realized responses of fish to these environments are expected to be mediated by their behavior, and specifically their differential utilization of various thermal habitats. While annual field surveys and tagging studies provide information on distributions and individual movement patterns, they generally only provide snapshots of distributions and movements of few individuals, and do not explicitly evaluate the behavioral mechanisms underlying distributional patterns. To this end, we designed a spatially-explicit individual-based model to evaluate movements and spatial distributions near thermal effluents for two fish species with differential thermal preferences; smallmouth bass and saugeye. We used observed water temperatures near the Tanners Creek power plant on the Ohio River to calibrate an existing thermal model (CORMIX) and predict the three-dimensional thermal plume downstream from the plant. Prey consumption and growth of each fish species (represented as super-individuals) were predicted using species-specific bioenergetics models. To consider the consequences of movement rules and select the most appropriate set of rules for future scenarios, we performed simulations where individuals were assigned a variety of movement rules and compared the resulting distribution patterns for both species. Modeling fish movements near industrial discharges will complement field studies and provide for more effective management of fish populations that are potentially directly influenced by anthropogenic activities.