Friends of the Upper Mississippi

Multisizer III particle analyzer used to sample mussel food particles in water.

Preliminary Research Evaluating Feed Acceptance of Lake Sturgeon to Commercial Diets Lake Sturgeon, a priority species of concern for fish and aquatic conservation, listed by many states as threatened, endangered and of special concern, has recently been petitioned to be federally listed under the Endangered Species Act. Due to its depleted status, many agencies throughout the United States have developed restoration plans consisting of restoring wild populations of Lake Sturgeon. The goal of intensive culture of Lake Sturgeon is to maximize genetic contribution and post-stocking survival to effectively restore populations through reproduction and recruitment. To increase juvenile recruitment and survival, the NFHS goal is to release fingerlings of an optimal size and fitness that can maximize post-stocking survival and avoid predation. To do this, managers strive to maximize growth and fitness of reared fish at the same time as controlling feed and operation costs. Traditional feeds consisting of brine shrimp, bloodworms, and krill have been widely adopted nationwide because Lake Sturgeon readily accept them, resulting in low feed conversions and survival of fish to stocking. However, these feeds are four times the cost of commercial dry diets and are relatively poor in nutritional quality, decreasing in availability, and may contain contaminants, which is an emerging concern for fisheries managers. Hence, Genoa National Fish Hatchery is conducting preliminary research to determine feed acceptance of Lake Sturgeon to commercial feeds. Results from this study will be used for future research, evaluating genetic selectivity, growth and survival of Lake Sturgeon fed commercial diets. Results from this preliminary study will be completed the end of July of 2020. By Orey Eckes
Genoa National Fish Hatchery’s mission is to recover, restore, maintain and enhance fish and aquatic resources on a basin-wide and national level by producing over 35 aquatic species of varying life stages, participating in active conservation efforts with our partners, and becoming a positive force in the community by educating future generations on the benefits of conservation stewardship.

Freshwater Drum juvenile- a valuable mussel host fish. USFWS photos.

 Megan Bradley at Endangered Higgins Eye Release. Photo by USFWS.

Megan Bradley of the Genoa (WI) National Fish Hatchery recently received high honors for her achievements in furthering Aquatic Species Recovery through her work in freshwater mussel and fisheries science. She recently received Fish and Wildlife Service’s (FWS) Region 3 2020 Award for Science Excellence. FWS Region 3 administers FWS activities and mission in the 8 Midwestern States of Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio and Wisconsin.

Megan’s contributions to the conservation of native freshwater mussels include working with partners to reintroduce a new population of Higgins Eye Pearlymussel according to the Higgins Eye Recovery Plan. Megan was instrumental in these efforts by constructing a preplacement habitat sampling program, and contributing to the writing of the Higgins Eye Reintroduction plan that paved the way for acceptance to place this new population of Endangered species in historic habitat in waters with low zebra mussel populations. This new population joined a newly transferred federally Endangered Winged Mapleleaf mussel population. Both species were propagated through efforts directed through a multi-agency mussel conservation team, and executed through the Genoa National Fish Hatchery mussel propagation program.

Megan is also considered an expert in determining economic value to mussel resources which is proving invaluable in determining damages in Natural Resource Damage Assessments. Her leadership and input in the Freshwater Mussel Conservation Society’s role in the formulation and publishing of the American Fisheries Society publication “Investigation and Monetary Values of Fish and Freshwater Mollusk Kills was invaluable. This reference is considered the standard in repairing the aftermath of fish and mussel kills and is used in many Natural Resource Damage Assessment (NRDA) settlements as a resource to determine damages.

Megan also developed methodology to determine ploidy in wild and cultured lake sturgeon using technology and equipment available on station. She is able to determine ploidy in wild populations, and pre-release sampling plans have been implemented to ensure cultured lake sturgeon will not negatively affect current restoration efforts ongoing across the country. Congratulations Megan! We are proud of you and your efforts!

Three tiny logperch can be seen in the red circle (above, left).  Photos by Megan Bradley/USFWS.

Hopefully you caught our article last month about spawning Logperch on station. Well, good news, the eggs we spawned are hatching and we have hundreds of Logperch fry going into a pond on station. Now, if you’ve seen other fish fry around the hatchery you might be surprised by these. The only sign that they’re in a tank is the tiny black eyes moving around in the water column. It looks a lot like you’ve sprinkled course ground black pepper, except that those tiny black specks are actively moving in the water column as the Logperch fry search for zooplankton to eat.

We were also able to use some of the Logperch adults that didn’t spawn as hosts for the federally endangered Snuffbox. In collaboration with the WI DNR we’re planning to restore Snuffbox populations in the Wolf River basin. About 20 days after the Logperch were infested we got our first Snuffbox juveniles dropping off. These first tiny babies (~150 ?m long) are growing at the hatchery as we wait for the rest of their cohorts to drop of the host fish. Hopefully these will soon go out into the Mobile Aquatic Rearing System to eat the natural food in Mississippi river water (bacteria and algae) and grow large enough to overwinter well at the hatchery for release in 2021.

By: Megan Bradley

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A smallmouth bass nest. Photo by Nick Bloomfield/USFWS.

Spring time means love is in the air at Genoa NFH. All of the brood fish we have on station, which includes Largemouth Bass, Smallmouth Bass, Bluegill, Black Crappie, Yellow Perch, Fathead Minnow, and Golden Shiner, were moved into their own ponds in March. These species are all suited for spawning in lentic environments, where there is no flow. This is in contrast to the spawning habits of fish like Walleye and Lake Sturgeon, where we need to spawn the fish manually and puts the eggs in a jar that mimics the flowing lotic environment until hatch occurs. This is much more labor intensive than the natural spawning that occurs in the ponds. All that we need to do for these brood fish is maintain water quality until it comes time to do some harvesting. Hopefully, these brood fish haven’t heard all the talk about social distancing and the hatchery will be crawling with little fish destined for areas throughout the Midwest and as future hosts for our mussel program!

By: Nick Bloomfield

Walleye nets are hung on a fence in spring. Photo by USFWS.

The weather has not able to make up it’s mind this year at Genoa, we have warmed up several times and then received snowstorms right after! In between the snow and rain, hatchery staff have been busy getting the station ready for the spring field season. The buildings have been sprayed down, cleaned up, tanks are getting set up, spawning ponds were set up with air stones and screens and nets are getting prepped for the river. As soon as tanks were set up in the Sturgeon Building, we began draining our host fish pond after it finally warmed up enough to melt most of the ice on the pond, allowing us to harvest the fish. Every fall, Genoa National Fish Hatchery will harvest the production ponds, collecting enough fish first for the mussel program and then any fish beyond that will be used for fish requests or to help out our state partners. The host fish then will either be used immediately for mussels that brood in the fall or will hang out over the winter to be used in the spring or summer the following year. Because of space constraints at the hatchery, the fish will over winter either in the mussel building, sturgeon building or in one of the hatchery ponds. The most of the fish kept in the mussel building will be the ones inoculated in the fall with either Winged Mapleleaf or Washboard Mussels. Access to the colder pond water helps to keep the channel catfish closer to their normal temperatures, reducing stress on the fish and the growing mussels over the winter. The sturgeon building only has access to well water over the winter, so the golden shiners and largemouth bass will spend their time in in there. They are much better suited to the more constant water temperatures. The remaining channel catfish not used, smallmouth bass and walleyes will spend the winter in the pond. These species survive much better following the normal cooling down and warming up of the water outside, and the extra space reduces stress on the fish as well. By Angela Baran-Dagendesh