Midwest Fish & Wildlife Conference 2019

AUTHORS: Kelly Mildebrandt, Lake Superior State University

ABSTRACT: Population genetics play a crucial role in wildlife conservation and management. Severe genetic bottlenecks can cause problems for long term viability of wild populations. Michigan’s elk population was reestablished in 1918 from seven known individuals of Rocky Mountain elk (Cervus elaphus nelsoni). Within the last 100 years that population grew to almost 1,400 individuals, declined to 200, and is now close to 1,200 elk. With the dramatic fluctuation in population size and the low number of founding members, evidence of genetic bottlenecking would be expected. Acquiring data on the genetic status of the Michigan elk herd would help wildlife managers and biologists make decisions on how to keep the local population healthy and thriving. Ninety two tissue samples were obtained from the 2017 Michigan Elk Hunt in Atlanta, MI. These are currently being analyzed for genetic diversity and evidence of genetic bottlenecking. The results will be also compared with recent research on the Rocky Mountain elk in its natural range.

AUTHORS: Bradley Dawson, University of Minnesota Duluth

ABSTRACT: Invasive fish species have caused numerous detrimental effects in the Great Lakes region. Basic life history knowledge of a species is necessary to accurately determine if the species is truly ?invasive?. One species, the tubenose goby (Proterorhinus semilunaris), is thought to have arrived in the Great Lakes in the 1990s via ballast water in trans-oceanic ships. This species has been poorly studied within North America, making it difficult to predict its effects on native ecosystems._x000D_
This study seeks to inform on the potential of the tubenose goby as a true invasive species within the context of the Great Lakes. Growth rates and seasonal diet patterns were examined from a population within the St. Louis River Estuary near Duluth, Minnesota, a tributary to Lake Superior. Growth rates and dietary breadth have ramifications for survival, competitiveness, and dispersal ability of fish species, influencing its potential success as an invasive species. Gobies were sampled from shallow vegetated habitat via a seine net during summer and fall periods. I removed otoliths and aged fish on daily and annual increments for growth modelling; furthermore, stomach contents were identified and weighed to provide measures of fitness and dietary breadth between seasons (fall vs. summer) and between several locations within the estuary. _x000D_
Preliminary results suggest a relatively low dietary breadth that is heavily dependent on Crustacea, regardless of location or season. Developing growth analysis indicates that tubenose gobies may be fast-growing and short-lived, indicating an r-selected life history.

AUTHORS: Cory Bauerlien, The Ohio State University

ABSTRACT: There is limited information regarding the effect that the invasion of Round Goby Neogobius melanostums into Lake Erie had on Walleye Sander vitreus diets and growth. Therefore, the purpose of this study was to evaluate the effect of Round Goby presence (pre-Round Goby = 1990-1996; post-Round Goby = 1997-2017) on Walleye diet composition and growth rate information. Analysis of variance was used to assess hypotheses regarding the effects of sex, age, habitat use, and temperature on diet selectivity (measured using Jacobs’s selectivity index) and growth parameters within the von Bertalanffy growth model.  While diet selectivity for Round Goby was not found, Walleye consumption of Round Goby was highest in August (p < 0.001), likely as a function of high surface waters (>22°C; p = 0.003) and location nearshore (i.e. ≤10m depth; p < 0.001). Walleye length-at-age, as well as growth coefficients, Linf and K, from fitted von Bertalanffy models, were higher for both male and female Walleye post-Round Goby, especially in younger individuals (ages 1-4).  The results presented demonstrate how aquatic invasive species may have the ability to affect native predator population characteristics. There may be other factors influencing the observed changes in Walleye growth, which should be addressed in future research.

AUTHORS: Jehnsen Lebsock, Western Illinois University; Brent Knights (USGS), Alison Coulter(SIU), Rebecca Neeley(USFWS), Matthew Shanks (USACE) and James Lamer (WIU).

ABSTRACT: Asian Carp are a highly invasive species introduced into the Mississippi River System in the mid 1970?s and now, due to expanding populations, are a pervasive threat to invading the Great Lakes. The Dresden Island, Marseilles, and Starved Rock Asian Carp populations in the upper Illinois River (leading edge) pose the greatest risk to the Great Lakes and therefore understanding their habitat use and behavior in this region are important for removal efforts to limit further expansion. Therefore, the objectives of our study were to use acoustic telemetry to determine habitat preferences and connectivity, and areas of concentration of silver carp, bighead carp, and grass carp at this leading edge of the invasion. We tracked the three Asian carp species from early March until November 2018 using a mobile Vemco VR-100 receiver at pre-defined grid points (0.54 km apart) within the three pools. Ninety-two tagged Asian carp have been detected (53 in Dresden Island Pool, 14 in Marseilles Pool, and 31 in Starved Rock Pool). Data from this study will be used to identify seasonal habitats of Asian carp to increase the efficiency of contracted harvest of potential Great Lake's Asian carp propagules. Continued research will result in a better understanding of the factors influencing Asian carp habitat use and connectivity to help predict these behaviors and target removal efforts. 

AUTHORS: Tyler Thomsen, Western Illinois University; Madeline Tomczak, Western Illinois University; Boone La Hood, Illinois Department of Natural Resources, Division of Fisheries; Kevin Irons, Illinois Department of Natural Resources, Division of Fisheries; and James Lamer, Illinois River Biological Field Station

ABSTRACT: Since the unintended introduction into the waterways of the southern United States in the 1970?s, Asian Carp have become widely established throughout a majority of the Mississippi River drainage basin. Abundances of Asian Carp have remained low in Pools 17, 18, and 19, due to the structural characteristics of Lock and Dam 19. Adult Asian Carp have been closely monitored, however larval fish communities in these pools have not been well characterized. The objectives of this study were to investigate and describe early life history of Asian Carp, as well as to describe larval fish habitat preference in the Upper Mississippi River. Early stages of Asian Carp require backwater reaches of riverine habitat to grow and develop. Quatrefoil light traps were used to sample for larval fishes from May to September of 2016 and 2017 when main channel water temperatures were above 17?C. To better determine habitat use, twelve light traps were deployed for a minimum of one hour at various locations representing several habitat conditions. The conditions sampled were recorded as woody or vegetation for cover, and open or shoreline for location. Weather conditions were recorded as calm or windy, as well as clear or rainy. Water quality was tested for each light trap location. Larval fish collected were enumerated, measured and identified to family. A total of 1,108 individual light trap samples were collected over the two-year period, representing twelve different families. A majority of the individuals identified were native cyprinid and centrarchids.

AUTHORS: Ciara McCarty, Minnesota Department of Natural Resources

ABSTRACT: As the second most harvested duck in the state, Wood ducks provide recreational hunting opportunity and funding for conservation through the purchase of hunting licenses. It is important for managers to understand the movement patterns of waterfowl in order to properly manage populations and conserve habitat to maintain a healthy population. There are no formal reports of where birds produced in the state migrate to and no way to test significant factors that drive migration. This project will utilize waterfowl banding data over the last 20 years to help describe some of the connections between production and harvest areas.

AUTHORS: Jake Kvistad, Central Michigan University

ABSTRACT: Rusty crayfish is the most widespread invasive crayfish in the Laurentian Great Lakes, where their documented effects include reducing macrophyte cover, displacing native crayfish, and consuming native fish eggs. Their role as egg predators has been implicated as an impediment to the recovery of native fish populations, such as lake trout and many coregonids, which utilize nearshore cobble reefs as spawning habitat. Despite this, an effective control strategy for rusty crayfish in the Great Lakes has not yet been developed. We tested a rusty crayfish control strategy on nearshore cobble reef spawning habitat in Little Traverse Bay, MIWe intensively trapped rusty crayfish off a treatment reef using a combination of standard gee minnow traps and modified pyramid traps prior to fall spawning of native fish and installed a set of physical barriers around the reef to slow crayfish recolonization after removal. A nearby reef was untreated and used as a reference site. Crayfish density was observed before, during, and after treatment at both sites from diver collections using replicate 1 m2 quadrats. Treatment effects on non-target species were also measured at treatment and reference sites, including benthic invertebrate and round goby densities. Egg bags were installed in treatment and reference reef habitat and seeded with eggs to measure the extent to which rusty crayfish removal on the treatment reef reduced predation pressure on native fish eggs. If successful, our strategy may be applicable for crayfish control in other Great Lakes reef habitats impacted by invasive crayfish.

AUTHORS: Peter Jenkins, The Ohio State University

ABSTRACT: Lake Erie management agencies estimate Yellow Perch (Perca flavescens) recruitment to the fishery (age-2) in part using the relative abundance of age-1 fish from the Ohio Division of Wildlife (ODW) western basin trawl survey in August. Currently, the ODW uses prespecified length classifications to classify the ?age? of 0, 1, and 2+ yellow perch on the boat. High variability in length at age between cohorts emphasizes the need for a more fluid length classification. The studies objective is to use seasonal growth data and environmental factors to help inform age-1 length classifications, thus increasing the accuracy of age-1 relative abundance estimates and reducing bias in recruitment estimates. Using pooled ODW monthly trawl data we compared a traditional von Bertalanffy growth model and Somers? and Pauly?s seasonal growth models using minimum AIC to determine the best fit model. Pauly?s model was determined to be the best and subsequent models were fit for each cohort from 2007 to 2015. There was high variability in model parameter estimates between cohorts so further analysis of biotic and abiotic factors were examined. we used the growth factor K? and correlated that to cumulative growing degree days, total fish density, young of the year yellow perch density, and mean zooplankton length. Only the growth factor K? and total fish density had a significantly positive relationship. We plan to translate this analysis into a hierarchical model to help improve our ability to predict length of August age-1 Yellow Perch in the western basin of Lake Erie.

AUTHORS: Zachary Witzel, Western Illinois University; Kevin Irons, Illinois Department of Natural Resources; James Lamer, Illinois River Biological Station, Illinois Natural History Survey, and Western Illinois University

ABSTRACT: Bigheaded carp (bighead carp and silver carp) are highly invasive fishes in the Mississippi River System and can be detrimental to native fishes and ecosystems. To limit their impact and further expansion, fishermen have been contracted through state and federal agencies to remove bigheaded carp using predominantly gill nets. Mesh size of entanglement gears determines the size structure of fishes able to be captured. To increase efficiency and effectiveness of bigheaded carp harvest and minimize the capture of bycatch, it is important to understand the relationship of gill net mesh size with the size structure of persistent populations. Therefore, the objective of our study is to determine the size of bigheaded carp and commonly encountered bycatch that are effectively caught in different sized gill nets based on their size (bar size = 7.62, 8.89, 10.16, 10.8, 11.43, 12.7, 13.335, and 15.24 cm). Gill nets were used in pools 16 through 20 on the Mississippi River to capture silver carp (n=445) and bighead carp (n=72). Multiple areas were targeted for their capture including backwater, and main channel areas of bigheaded carp. With this information managers will be able to more efficiently target bigheaded carp if knowledge of population size structure is available.

AUTHORS: Erik Carlson, University of Wisconsin-Milwaukee

ABSTRACT: The offshore migration habits of the invasive Round Goby (Neogobius melanostomus) in Great Lakes is based on anecdotal information. When Round Goby move offshore, they have the potential to become prey items for fishes like Lake Trout, Burbot, and Brown Trout. Due to the Round Goby?s preference for rocky habitat, it is difficult to sample using traditional methods, such as trawls. To better understand this movement, and the factors that drive it, a remotely operated vehicle (ROV) equipped with a tracking system was used to observe the number of fish along transects, and to collect specimens for diet and aging purposes. In this study, six ROV transects per site were taken at depths of 10 meters to 40 meters in 10 meter increments. Initial observations showed more goby nearshore (10 m site) in September (1.71 fish per transect meter) and decreasing to 0.15 fish per meter, while at 30 m abundance increased from 0.03 fish per meter to 0.41 fish per meter by the end of October. A 2-Factor ANOVA, with depth and time of year as the two factors, showed significant results for the interaction between depth and time of year. The main factors are not interpretable when the interaction is significant. Additional transects will be conducted in spring to observe the return of Round Goby back to nearshore habitat.

AUTHORS: Jessica Weir, Ball State University

ABSTRACT: Some of the largest threats to diversity include overexploitation and aquatic invasive species (AIS) spread. Recreational fishing and boating are vectors of AIS, and management is often concerned with minimizing the risks associated with angler movement across the aquatic landscape. While data collection and mitigation projects for management and conservation often involve expensive specialized equipment, multiple man-hours, and proper training for the individuals carrying out the work, there exist more economic modes of passive data collection. Smartphones, utilized by millions worldwide, come standard with data-gathering tools including GPS and high-resolution digital cameras. This hardware, paired with broad network coverage, creates an exciting opportunity for sharable, mobile measurement of fisheries data. Fishbrain is a privately-owned smartphone application that is available for free worldwide, generating an extensive local, national, and international network of recreational anglers. The app users connect with each other and voluntarily share angling information about their fish catches. Data stored and freely shared with scientific research partners include: species identification, size, geographic location, and fishing method. In this study, we will utilize the geographic information to assess the fine-scale movement of recreational anglers. More particularly, we are mapping the movement of anglers as a network of aquatic connectivity across the United States and Canada to compare to current distributions of AIS. The next phase of this study will compare the angler connectivity network to the existing hydrologic connectivity network as vectors of AIS spread.