Genoa NFH mussel biologists have been busy this summer tagging juvenile mussels prior to their release into local rivers. One of the last batches of mussels to be tagged are a cohort of 3000 Salamander Mussels that were propagated in 2018 and are now ready for release. These mussels have been tagged with a black glue dot on each valve, or side of the shell, so during future survey efforts researchers will be able to tell if a found animal was propagated at the hatchery or is the result of natural recruitment. Later this summer, we’ll be working with partners from the Wisconsin DNR to release these mussels into the lower Chippewa River. Salamander mussels are a smaller mussel species, with mature adults reaching about 2” in length. These mussels are found only in specific sections of large and medium sized rivers in the Midwest, as they prefer very specific habitats conditions. Salamander mussels can occasionally be found in high abundance in protected spots under large flat rocks or the submerged ledges along cliff faces, near- but protected from- swift flows.
It is not a coincidence that these very specific habitat preferences are also the preferred habitats of the Mudpuppy (Necturus maculosus)—the aptly named Salamander Mussel is the only North American freshwater mussel species that uses a non-fish host to complete its lifecycle. The process is the same- Salamander Mussel glochidia attach to Mudpuppy gills just like other species’ glochidia attach to fish gills, then, when development is complete, drop off the host animal and settle into the sediment- in this case the protected spots under large rocks where the Mudpuppies spend much of their time. After release this fall, we hope these juveniles will be able to settle in good habitats with healthy Mudpuppy populations, and help this interesting mussel species maintain healthy populations in the Chippewa River! By Beth Glidewell
Juvenile Salamander Mussels with a black superglue dot on each valve are kept in a tank at the hatchery while waiting to be released into the Chippewa River. Photo credit: Beth Glidewell/ USFWS.
Even 2020 is proving to be a good year for mussel production at GNFH. The most exciting moments of any year of production is when we first start seeing new juveniles in our tanks. Since mussels start out so small (<200 ?m), only once they’ve grown to more than a millimeter in length do we have confidence in their survival. A month or so after juveniles are placed in tanks in the Mobile Aquatic Rearing System (MARS), or Mussel Trailer, our biologists find themselves ever so gently feeling along the bottom and edges of the tanks for the tiny pebbles that might be growing juveniles. Sometimes instead of pebbles, when we draw our hands from the water we have mussels attached to our fingers by a web of their byssal threads. This year was no different. After weeks of careful dabbling one day I drew up a tiny Black Sandshell and when I searched the front edge of another tank I found, not the tiny juveniles we usually find, but substantial animals that will be ready for release this fall.
We started the year with Giant Floater production in February. These juveniles grew in plastic shoe boxes in the mussel building until the water warmed enough for the trailer to be deployed. This species grows quickly once the water begins to warm. They reached the size of dimes by mid-July.
Black Sandshell production started later in early June and most of the juveniles went out into ponds at the hatchery still attached the Walleye, but a few fish were held back to see how many juveniles might be in any cage. These juvenile mussels went into the trailer and they’re bigger than the head of a pin, or about a millimeter in length. These tiny animals are growing quickly for their shell thickness. We find that for most species the thinner the shell the more quickly juveniles grow. Black Sandshell produce a substantial shell that allows them to be stable in rocky runs on the Mississippi and tributaries, while the Giant floaters grow in the finer substrates in lower flow areas.
By: Megan Bradley
Giant Floater juveniles (dropped off the fish in February 2020), approximately the size of dimes.
Our world has changed dramatically in the past few months. Even in the world of fish production. In a typical year, the Genoa National Fish Hatchery (GNFH) would go off station to collect eggs from 6 river strains of wild lake sturgeon to raise to fingerling size to reduce predation. Then they would be stocked in a number of different locations to restore lake sturgeon within its historic range. This year in the middle of a global pandemic all off-station travel was ceased in order to protect staff and others from the novel virus. Only one lake sturgeon egg take was actually accomplished in New York out of the 6 active programs that the station is involved in. This was due to its occurrence happening in early June, when restrictions were easing in upstate New York. Our partners in Conservation, the New York Department of Environmental Conservation, (NYDEC) with the assistance of the Fish and Wildlife Service’s New York Field Office (NYFO) collected and shipped the eggs overnight via FEDEX to the station in order for us to continue this restoration effort in Calendar Year 2020. The eggs were in great shape and hatched out well. So well that surplus fish were available for shipment back the state of New York. In a normal year, we would load up the smaller surplus fish in August and drive them out to our partners in New York as a precursor to the final distribution of an additional stocking of 7 inch fish in mid-October.
This year with travel still unavailable a new plan had to be formulated. As with the eggs, the only mode of transport available to us was via FedEx. Not having shipped lake sturgeon with this method over this long distance by air was a little disconcerting at best. Using the limited information available in “grey literature” from other species of fish we set out to document the actual effectiveness of this method of transportation on lake sturgeon small fingerlings of less than 2.5 inches. To date, the station has shipped 10,000 small fingerlings using this method back to New York for stocking by New York DEC and FWS’s NYFO personnel by priority overnight airmail with minimal loss. In a normal year, this method would not be considered given the uncertainties of air freight travel, but in this instance, desperation leads to innovation. Through 20 boxes of freight, 10,000 2 month old fish measuring 2-2.5 inches were distributed in their native habitat. In the year of 2020, we are going to try to count this one as a win.
By: Doug Aloisi
Top- Lake Sturgeon fry pre-shipping. Bottom- Boxed lake sturgeon fry – Photo Credit:Doug Aloisi/USFWS
On July 1st, 2020, the hatchery received 12 devil crayfish from the Forest Preserve District of DuPage County to see how they would grow and survive using the same rearing techniques as the Hine’s emerald dragonfly. The Forest Preserve had collected the eggs in 2019 and with the excellent survival last year and over the winter, was planning for the crayfish to go to local schools as part of an outreach program. With the outbreak of COVID-19 and schools being closed, the programs were unable to start up in 2020 and the crayfish were outgrowing their homes, starting to fight one another, causing damage, missing claws, etc.
The transfer to Genoa allowed the Forest Preserve to reduce their numbers and allowed Genoa to try rearing a new species. Upon arrival, the crayfish were individually swabbed, and those samples sent to the La Crosse Fish Health Center for disease testing. They are being housed in the dragonfly trailer in cages to allow pond water to flow through to provide zooplankton for food and then the effluent water is discharged off station to prevent any possible outside contamination while the disease testing is pending. To date, they have survived the first couple molts, indicating they are eating well and the water quality is good for the crayfish [Continued on
[Continued from Page 2] These crayfish are an important part of the habitat for the Hine’s emerald dragonfly, their extensive burrows with chimneys provide a home to the larval stage of the dragonfly during times of drought and over the winter. Future work with this species will include studies of how they move, what materials they will use for burrows and to see if they will stay in locations where they are stocked, creating habitat for the dragonflies.
Top: Crayfish being swabbed for disease testing. Bottom: Crayfish in individual cages. Photo by Angela Baran Dagendesh /USFWS Photos.
By Angela Baran Dagendesh
Sometimes the stars align just perfectly that allows us to partner with some of our traditional partners in a relatively new emerging resource area such as mussel restoration. It especially works well when our partners are as passionate about the resource as The St. Regis Mohawk tribe of northern New York. The hatchery has an ongoing relationship with the tribe involving lake sturgeon restoration. Genoa has been actively supplying lake sturgeon fingerlings for northern New York waters since 2011. The tribe has recently become interested in freshwater mussel propagation for restoration due to recent tribal aquatic resource recovery plans that include mussel restoration using propagation as a recovery tool.
Further contacts were made when tribal biologists attended the Freshwater Mussel Propagation for Restoration course at the FWS National Conservation Training Center in Shepherdstown West Virginia. Genoa mussel biologists assist in the teaching and formulation of that class as well as the Conservation Biology of Freshwater Mussels course offered
there. Through these classes a relationship was formed and we agreed to assist in drafting a cooperative agreement in order to further the tribe’s freshwater mussel propagation program through technical expertise and assistance, providing host fish of various species, analyzing food content of the tribes hatchery water supplies, and by reviewing designs of the tribal hatchery in order to suggest improvements relating to freshwater mussel propagation.
In the past year, this partnership has proven effective by supplying 2 shipments of freshwater drum, a host fish for 2 species of concern referenced in the lower Grasse River Mussel Recovery plan. Also provided to the tribe was a review of their newly constructed mussel propagation lab and review of the Quality Assurance Project Plan focusing on freshwater mussel propagation This is a great start to a valuable partnership to conserve fish and aquatic resources in tribal waters. We look forward to the future and all of the potential opportunities at hand to further stewardship of aquatic resources with the St. Regis Mohawk Tribe.
Bt Doug Aloisi
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