Hatchery biologists have spent the last several weeks preparing juvenile mussels of several species for release into the Mississippi River near Guttenberg, Iowa. This is stocking event is part of a multi-year effort to restore the mussel population in an area of the river that suffered severe impacts from a train derailment. Black Sandshell, Yellow Sandshell, Plain Pocketbook, Washboard, and Higgins Eye mussels were propagated at Genoa NFH, and have been reared at the hatchery, in the MARS ‘mussel trailer’ and in submerged containers in the Dubuque Ice Harbor (in collaboration with the National Mississippi River Museum) for the last 2- 3 years.
With high water for much of last fall, we and our Iowa DNR partners were not able to stock juvenile mussels at the site during 2019. This summer, with good river conditions the juvenile mussels were ready for the river after spending an additional winter and spring in the mussel building at Genoa NFH (the mussel biologists were also ready for the several thousand, rapidly growing juvenile mussels to go to the river!).
Prior to release, juvenile mussels are marked or tagged so future monitoring efforts can determine if a mussel was propagated or has resulted from natural reproduction or is an animal that has moved into the target area from surrounding areas. A colored super glue dot is added to one or both valves of the shell for most species, or in the case of Federally Endangered Higgins Eye mussels, a tag with a unique number is glued to the shell. When all of the mussels were counted and tagged, they were loaded up into big transport coolers, taken to Guttenberg, transferred to biologists from the Iowa DNR, and released into the Mississippi River. Hopefully the little mussels will settle in and help establish a healthy, stable mussel bed for years to come.
By Beth Glidewell
Washboard mussels laid out for glue dot tagging.
Higgins Eye with newly affixed numbered tags.
Pocketbook juveniles laid out for glue dot tagging prior to release in the Mississippi River near Guttenberg, Iowa. USFWS photos.
Fat Mucket juveniles produced during the 2019 pond season in Pond 14 North.
Mussel culture has grown throughout the last several years, but it is nowhere near the same place fish culture is. When it comes to fish, we have over a century of science to fall back on. When we run into a problem, there is a very good chance someone has had that same problem and tried different solutions. Freshwater mussel culture, on the other hand, does not always have that knowledge to fall back on. That means we get to be the tinkerers.
In 2019, we completed a study looking at mussel survival and growth in the twin ponds at the east edge of the property, ponds 14 north and south. We looked at water quality and food quantity in an organically fertilized pond vs an inorganically fertilized pond. While we didn’t see any difference in survival, we were able to grow substantially larger mussels in the inorganic pond, with no effect on fish production in either pond.
This year, we are trying something similar with additional mussel species. The inorganic vs organic pond is still in play, but we went without Aquashade in the inorganic pond and reserve the right to add algaecide if necessary. Aquashade dyes the water to limit sunlight penetration, slowing primary production and growth of aquatic vegetation. Algaecides can be toxic to mussels, but we want to see whether the small amounts used in typical fish production are problematic. Every little piece of information we can glean from these small-scale studies can be used to increase our ability to grow more and bigger mussels to help us achieve our mission.
By Nick Bloomfield
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.
A couple of thousand Fatmucket mussels were recently added to a small creek in downtown Dubuque, IA. Upper Bee Branch is a unique project for freshwater mussel restoration because the stream has, until recently, been covered by concrete and the streets of the city. The National Mississippi River Museum collaborated with the Dubuque County Conservation Board and Genoa National Fish Hatchery to return mussels to this urban creek. Freshwater mussels raised at the hatchery are released into the wild for several reasons; to restore the diversity of a community impacted by historic or recent pollution or physical environmental change, to increase the number or size of a population of an endangered species, or simply to restore their ecosystem services (water filtering) to a stream.
Releasing freshwater mussels is the easy part. They don’t squirm in your net, flip their tails and splash you or hide in the back corner of your stocking tank, however, they’re expert burrowers. This seems like it should make it easier to come back and check on how they’re doing, but unfortunately, this is rarely true. Finding a mussel in the creek is very much like seeking the proverbial needle in the haystack, even a haystack as small as the Upper Bee Branch, which is only a yard or so across. This means that in places where scientists want to regularly assess growth and survival, mussels can’t just be dropped into the stream. In the case of Bee Branch, silos, or concrete mussel containers have been placed out and only a handful of mussels put in a chamber where there’s steady water flow. This means that the mussels won’t be washed downstream in high flow, and they’re easy to find when sought. National Mississippi River Museum staff check on the mussels and measure for growth once a week over the summer to ensure that the creek will support the survival of this returning species.
Juvenile Fatmucket mussels ready for deployment into silos in Bee Branch, Dubuque, Iowa. Their size at the end of the growing season will be compared to their early season size (shown here, relative to a quarter). USFWS photo
By Megan Bradley
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!
Hine’s Emerald Dragonfly larvae are reared in PVC pipe cages submerged in tanks. Photo by Angela Baran Dagendesh/USFWS.
Genoa National Fish Hatchery began working with the Hine’s Emerald Dragonfly in 2015 after receiving a grant to help get the program underway. Each year brings new challenges and learning opportunities for working with this species! Last fall, the hatchery received 800 eggs to hold over the winter for spring hatch and summer grow-out. The learning curve has been quite steep for the eggs and newly hatched larvae, with hatching beginning in February this year, about 3 months early! The hatchery adapted quickly, setting up small cups with a little sand and supplementing with pond water out of the mussel building, warmed up to room temperature. Once it warmed up and pond water temperatures increased, the newly hatched larvae were placed loose in rearing tanks, to give them more space and hopefully avoid cannibalism. We are now transitioning to smaller cages to place in the tanks to further reduce cannibalism and also to protect the larvae from any other invertebrates that might come in with the pond water. Now that the temperatures have warmed up, zooplankton production in the ponds has taken off, providing an all you can eat buffet for the larvae! Once the larvae get a little larger, they will transition to the larger mesh cages and be placed out in the hatchery ponds. The larger mesh will still protect the larvae, but allow larger sized food to crawl in for the dragonfly larvae. Stay tuned this summer for updates and pictures of the growing dragonflies!
By Angela Baran Dagendesh
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
In 2019 GNFH biologists experimented with two ponds to see whether there was a difference in freshwater mussel survival from drop-off to about 6 months old in ponds that were fertilized with organic vs inorganic materials. Various water quality measures were made daily or weekly throughout the growing season, including algae (mussel food) levels in each pond, to track the effectiveness of each fertilization type. Both methods were successful, and the two ponds combined produced over 35,000 Fat Mucket (Lampsilis siliquoidea) mussels. This experiment is continuing in the 2020 season, and expanding to include two different mussel species, Black Sandshell (Ligumia recta), which use Walleye as a host, and Plain Pocketbook (Lampsilis cardium), which use Largemouth bass as a host.
In late May, hatchery biologists collected mussel larvae, called glochidia, from gravid mussels (Photo 1, gill filled with glochidia), allowed the glochidia to attach to the gills of their Walleye fish hosts in a bath exposure (Photo 2). When the mussels fully metamorphose from larvae into juveniles, they’ll drop off the fish’s gills and (hopefully!) fall into the sand in the bottom of the cage. These little mussels will start filter feeding and growing, and – later in the fall—we’ll carefully take the cage out of the pond, sift through the sand, and count and measure the juvenile mussels that were produced, comparing the outcomes between the two ponds.
Improving our ability to manage ponds for both fish and mussel production concurrently– and culture sand grain sized juvenile mussels past this first, sensitive life stage in hatchery ponds instead of in often unpredictable Mississippi River conditions—will help to make future mussel production more effective and reliable.
By: Beth Glidewell
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
Attendees listen to Frog Monitoring Volunteer, Ben Johnston, as he describes the mnemonics of frog calls. Photo by USFWS
36 people made their way to the interpretive center on Saturday, March 7 to learn about Wisconsin frog calls. Ben Johnston, volunteer frog monitor for Wisconsin DNR, taught audience members 11 frog calls and 1 toad call. Participants had an opportunity prior to and after the event to view living frogs, make a frog life cycle, or make a jumping frog. A huge thank you to Ben Johnston for providing such an interesting presentation! By Raena Parsons