Midwest Fish & Wildlife Conference 2019

AUTHORS: Eric Miltz-Miller, Dr. Jill B.K. Leonard – Northern Michigan University

ABSTRACT: Several species of larval stream salmonids dwell in winter stream conditions from spawning through their early larval stages, yet relatively little is known about the effect of winter habitat variability on these fish. Three Northern Michigan streams were selected based on winter conditions: No ice (stable/unfrozen), dynamic/intermittent ice formation, or constant ice throughout the winter (stable/frozen). Streams had two study sites, each with two artificial redds, two incubation boxes, and two natural redds. Wild brook trout (Salvelinus fontinalis) were field spawned and the resulting embryos stocked into artificial redds/boxes in the stream from which the parent fish originated. Larvae were collected at swim up and evaluated for stage/morphology. Our results show that embryos transplanted to non-natal stream sites, with lower average winter temperatures than their natal streams, resulted in longer intra-gravel periods, and larvae swam up at a less developed stage than in their natal sites. These results are important since all the streams in the study are currently managed as a single population, yet considerable variability in larval characteristics was generated by small-scale winter habitat variability.  Further, these results allow us to consider effects on brook trout of predicted climate changes in small streams based on winter conditions.

AUTHORS: Joseph T. Mrnak, Department of Natural Resource Management, South Dakota State University; Steven R. Chipps, South Dakota Cooperative Fish & Wildlife Research Unit, South Dakota State University; Daniel A. James, U.S. Fish and Wildlife Service

ABSTRACT: Pallid Sturgeon Scaphirhynchus albus are a federally endangered species endemic to the Missouri River basin and the lower Mississippi River. Natural reproduction of Pallid Sturgeon is negligible in the Missouri River with a recruitment bottleneck believed to occur during the drift phase of endogenous development. Understanding factors that affect survival of Pallid Sturgeon larvae is key given their critical status and ongoing recovery efforts. In this study, we evaluated the effects of water temperature on growth, energy reserves, survival, and settling time of endogenous Pallid Sturgeon larvae (<25 mm TL). We tested three water temperature treatments at a velocity of 8.9 cm s⁻¹; treatments included low temperature (18.7 °C), medium temperature (20.4 °C), and high temperature (23.3 °C). Larvae maintained at the high temperature exhibited significantly greater growth rate (1.05 mm d⁻¹) than larvae maintained at medium and low temperatures (1.04 and 1.03 mm d⁻¹, respectively). Energy reserves of Pallid Sturgeon larvae maintained in the high temperature treatment declined significantly compared to larvae in the medium and low temperature treatments. Moreover, larvae in the high temperature treatment experienced significantly greater mortality and settled on the bottom significantly faster than those in the medium and low temperature treatments. Increasing river water temperatures by manipulating water releases from upstream dams may provide a potential restoration option by shortening the development time and thus the drift distance required during the endogenous phase of Pallid Sturgeon larvae.

AUTHORS: Kevin Haupt, U.S. Fish and Wildlife Service; Hae Kim, West Virginia University Division of Forestry and Natural Resources; Donovan Henry, U.S. Fish and Wildlife Service; Sara Tripp, Big Rivers and Wetlands Field Station Missouri Department of Conservation; Quinton Phelps, West Virginia University Division of Forestry and Natural Resources

ABSTRACT: Larval fish sampling can provide insight into early life vital rates, abundance, and drift dynamics. In riverine environments, larval fish drift dynamics may influence early-life survival. Further, field and lab studies have shown that drift dynamics vary across species. Thus, information during this life stage is imperative for proper conservation and management of riverine fishes. However, successfully sampling larval fishes in riverine environments presents various challenges (e.g., spatial and temporal coverage and sampling effectiveness). As it relates to Scaphirhynchus sturgeon, these challenges are exasperated when targeting larvae in fast flowing reaches of the Missouri and Mississippi rivers. Prior research suggests that Scaphirhynchus sturgeon are benthic post-hatch. Our objectives were to determine drift dynamics and origin of Pallid Sturgeon in the Missouri River, Middle Mississippi River, and Upper Mississippi. We sampled in river reaches above and below the confluence of the Misssouri River, above chain of rocks and below chain of rocks on the middle Mississippi. We employed two 1000µm mesh, rectangular framed-nets off both sides of the boat. Weights (45kg) were affixed to the bottom of each net, to keep nets upright. Additionally, flow-meters were affixed to the mouth of the nets to measure volume of water filtered. Nets were deployed from the boat via an electric winch. Sampling commenced in mid April and ended in late June.  Overall, approximately 3,500 larval drift samples were collected during the study period.  Preliminary results indicate we have captured drifting Scaphirhynchus sturgeon throughout the water column (i.e., surface, middle, and bottom) at all river reaches.  To this end, employing larval drift nets throughout the water column may provide additional insight into Scaphirhynchus sturgeon life history that will inform conservation and management of these species.

AUTHORS: Jason Gostiaux, Contractor at US Geological Survey; Edward F. Roseman, US Geological Survey; Robin L. DeBruyne, University of Toledo; Jason L. Fischer, University of Toledo; Ashley Moerke, Lake Superior State University; Kevin Kapuscinski, Lake Superior State University; Christopher Olds, US Fish & Wildlife Service; Faith Vandrunen, Contractor at US Geological Survey; Kaley Genther, US Fish and Wildlife Service; Ethan Binkowski, Lake Superior State University

ABSTRACT: The St. Marys River is the Great Lakes connecting channel connecting Lake Superior to Lake Huron and is the international border between Michigan, United States, and Ontario, Canada.  This large river has a variety of habitats present including lakes, wetlands, islands, tributaries, side channels, and main channels.  Water flow is regulated through the navigational locks and a series of 16 compensating gates immediately upstream of the area known as the St. Marys Rapids.  This area is considered an important spawning and nursery area for numerous fish species, although no research has been done to assess fish use or production.  To address this knowledge gap, active and passive larval sampling gears were used to measure the timing and abundance of larval fishes upstream and downstream of the St. Marys Rapids area from May-August 2018.  Drifting eggs and larvae were collected near the bottom and surface during weekly daytime and nighttime sampling.  Eggs and larvae of several native (suckers, sculpins, troutperch, minnows) and introduced species (rainbow smelt, salmonids) were collected at sites above and below the St. Marys Rapids area, however, larval fish and eggs were more abundant below the St. Marys Rapids.  Furthermore, salmonid and lake sturgeon larvae were only captured downstream of the rapids area.  Lake sturgeon larvae have been documented in the Garden River, Ontario, a tributary of the St. Marys River, however, this is the first contemporary documentation of successful lake sturgeon spawning and larval drift within the St. Marys River proper.  Evidence of fish use of the St. Marys Rapids including the presence of multiple sensitive species, confirms the importance of this area for spawning, production, and biodiversity.

AUTHORS: Jason L. Fischer, University of Toledo, Lake Erie Center; Edward Roseman, US Geological Survey, Great Lakes Science Center; Christine Mayer, University of Toledo, Lake Erie Center; Todd Wills, Michigan Department of Natural Resources, Lake St. Clair Fisheries Research Station

ABSTRACT: Artificial rock reefs have been used to remediate spawning substrates for lithophilic spawning fishes (e.g., Lake Sturgeon, Acipenser fulvescens;Lake Whitefish, Coregonus clupeaformis; and Walleye, Sander vitreus) in the St. Clair-Detroit River System. Early projects used species specific metrics (e.g., proximity to historic spawning locations) to guide reef placement. However, long-term success of some of the initial reefs was compromised by accumulation of fine sediments. Therefore, to improve the likelihood of successful reef function, project managers incorporated geomorphological criteria in 2013 to avoid placing reefs in areas near sediment sources and depositional zones. To evaluate the effectiveness of the revised placement process, we quantified physical maturation of artificial reefs using 1) annual down-looking and side-scan sonar surveys beginning in 2014 to measure reef areas and bottom roughness and 2) underwater video surveys beginning in 2015 to quantity sediment composition. Roughness of reefs constructed after 2013 remained greater than bottom roughness in areas adjacent to the reefs thru 2017, however, roughness of the Hart’s Light Reef was significantly lower in 2017 than in 2014, indicating some sediment accumulation. Similarly, sediment composition of the reefs remained similar thru 2017 and prevalence of reef rock was high, except at Hart’s Light Reef, where dreissenid mussel shells composed 32% of the substrate by age three. However, in 2018 reef rock was less prevalent at all reefs, due to accumulation of shells, fine sediments, and gravel. Despite the use of geomorphic criteria to identify areas most suitable for reef construction, sediment composition of the reefs has changed and long-term evaluation is required to determine if the changes observed in 2018 are temporary or representative of a longer trend. Nevertheless, our evaluation indicates future reef restoration projects could benefit by incorporating methods for maintenance, in addition to using geomorphic criteria to identify restoration sites.