As production season winds down, things start to slow down a bit at the hatchery. However, that doesn’t mean we don’t have fish on station. We hold on to several species for different reasons throughout the winter. We currently have four of our ponds set up to overwinter fish.
One of these ponds is dedicated to finish growing out the Rainbow Trout hatched last winter. These will be grown as much as possible until the end of April when they will be stocked out as catchable sized trout. Another pond is dedicated to keeping our “fishing day” fish, mainly Rainbow Trout with some fun surprises sprinkled in. There are some absolute monsters in there, partially due to the fishing day cancellations in 2020. The next fishing event will be epic, whenever that might be!
Another pond is dedicated to all the broodstock sportfish on station, including Yellow Perch, Bluegill, Largemouth Bass, Smallmouth Bass, and Black Crappie. They will be divided into their own ponds come spring. Finally, a pond is used by some of this years’ Walleye and Smallmouth Bass crops. These are destined to become host fish for the mussel program in 2021. More current and future mussel host fish can be found inside the buildings. Channel Catfish, Freshwater Drum, Walleye, Golden Shiner, and Flathead Catfish are all waiting their turn to carry around some baby mussels. Never a dull moment!
By: Nick Bloomfield
One of the broodstock ponds with the 20-21 season’s first dusting of snow. USFWS photo
Feeding the Rainbows- an automatic feeder distributes feed to hungry Rainbow Trout. USFWS photo.
A very cold team effort to remove the pump and filter cage unit that supplies Blackhawk Slough/Mississippi River water to the trailer all season.
At the end of the summer growing season, juvenile mussels that have been cultured in the MARS trailer all summer are counted, measured, and moved to the mussel building at GNFH for winter culture. The MARS trailer is also brought back to the hatchery, cleaned, needed repairs are made, and is winterized for storage until next spring.
The MARS trailer is installed at Blackhawk Park each year as soon as spring flood waters recede, with electricity to run air and water pumps, clean water to maintain the filtration system, and UV sterilization systems operating as biosecurity measures. These features make the MARS trailer a very productive culture system for many species of juvenile mussels, and also require a team effort to close-out the system at the end of the season. We were lucky to have low water levels and several balmy Wisconsin fall days to pack up the trailer, haul the water pump and its filter cage out of the slough, bring everything back to the hatchery, and power wash away a season’s worth of river mud, algae, bugs, and unwanted pests.
The juvenile mussels that spent the summer in the MARS trailer are now settled into their winter homes in rearing pans and baskets in the mussel building. This year, the mussel building is getting a major renovation: in addition to a re-design of the rearing pan system, the last picture below also shows insulated building walls and a new head tank for incoming pond water. We’ll feature these and many more upgrades to the building in an upcoming issue of Genoa News and Notes!
By: Beth Glidewell
Higgins Eye juveniles settle into their winter home in the mussel building.
Megan adjusts water flow to pans in the newly redesigned system. Photos by Beth Glidewell/USFWS.
The Fish and Wildlife Service celebrated November as Native American Heritage Month, a time the Service used to reflect on the rich history and cultures of Native Americans both past and present, and their importance to natural resource conservation in the future. The Genoa National Fish Hatchery, along with our Fish and Wildlife Conservation Offices work very closely with tribal conservation offices to assist in the conservation mission of the tribes on their tribal lands and waters. This is part of our nation’s tribal trust responsibilities, many spelled out in treaties signed by the U.S. government with the tribes sometimes many years ago. The Genoa (WI) National Fish Hatchery actively works with 12 Midwestern and Northeastern tribes to assist them in the Recovery of Threatened and Endangered Species, the Restoration of Native species of fish, and the creation of sport fisheries that are enjoyed by tribal members and non-members alike.
All of this happens over a large landscape of sovereign tribal lands and waters. Endangered species such as the freshwater mussels are supplied and propagated in tribal hatcheries. Lake sturgeon and Coaster brook trout are supplied to tribes through targeted restoration plans in order to assist in species recovery over their historic range. Also recreational fish species such as Walleye, Rainbow trout, Brook trout, Bluegill, Black crappie, and Largemouth bass are also supplied to tribes to meet their fisheries management objectives.
The Genoa staff always consider meeting our tribal commitments with a measure of respect and honor, and while November is specifically chosen as Native American Heritage Month, it is celebrated year-round through the cycle of life at the Genoa facility.
By Doug Aloisi
(Top) A Tribal biologist fin clips hatchery Coaster brook trout recaptured from a wild fish population survey. Photo Credit: FWS photo. (Below) A Tribal biologist holds hatchery lake sturgeon recapture. Photo Credit: Pat Brown
GNFH truck at the stocking site at Devil’s Lake, Forest County. Photo by Nick Bloomfield/USFWS.
September and October were busy months at Genoa National Fish Hatchery. Pond harvesting and distributing those harvests kept us on the move for a couple month stretch of time. One of those trips was made up to our tribal partners in the northern part of Wisconsin with a load of Black Crappie, but there was truly nothing crappy about them. These little gems are destined for life in smaller lakes ideal for panfish. On 9/24, I set out for the long round trip to two lakes. Devil’s Lake is located on Forest County Potawatomie lands in northeastern Wisconsin. Oneida Lake is just west of Green Bay on Oneida Nation lands. Each lake received 2000 Black Crappie and some Fathead Minnows to grow on. It gave me a chance to break out of Vernon County for a day and get a nice preview of the fall colors that were working their way towards our neck of the woods. Hopefully some of these fish will find the end of a fishing rod in the next few years!
By: Nick Bloomfield
(Right) Mussels are distributed across known mussel habitat (a mussel bed) at the stocking site. Photos by Beth Glidewell USFWS.
While not many aspects of 2020 have been “normal”, we have been lucky to have historically average water levels on the Upper Mississippi River. Conditions have remained favorable for releasing juvenile mussels well into the fall months, so we were able to do a second round of stocking of hatchery reared juvenile mussels to a site near Guttenberg, Iowa this October. Several hundred black sandshell juveniles and plain pocketbook mussels had grown enough over the summer in the MARS trailer to be of stocking size –longer than about 15mm, which will increase their likelihood of survival when released into the natural mussel bed in the river. The juveniles were tagged with a glue dot so they can be recognized as hatchery reared juveniles (though produced from wild parents) during future survey efforts. Stocking juvenile mussels in the fall still allows them time to settle in and get safely burrowed in the sediment before winter and the spring’s high water levels, then be ready to grow as soon as the waters warm in the spring.
A large group of juvenile mussels were stocked to this location earlier in the summer in collaboration with Iowa DNR. While at this location, we were also able to SCUBA dive and collect broodstock- primarily Hickory Nut mussels- for next year’s propagation efforts. We’ll hold these broodstock animals over the winter at GNFH, use their larvae to inoculate host fish in the spring, and in a couple of years, have juvenile mussels to release and further improve the mussel bed at Guttenberg.
By: Beth Glidewell
When things are left in the river they become habitat for all of the animals that live there. Mussel cages are no different. Despite our best efforts, a handful of cages were left in the St. Croix River for more than 4 years. There wasn’t much left except the bases that still provided excellent habitat for native mussels. It’s unlikely that the mussels crawled in themselves, instead it’s likely that their host fish were hiding in the structure provided by the bases and the juvenile mussels dropped off and grew there. Species found included Endangered Higgins Eye, Plain Pocketbook, Fatmucket, Paper Pondshell, Giant Floater, Pink Heelsplitter, Threeridge, White Heelsplitter, Mucket, Creeper and Cylindrical Papershell. While we were recovering the cages we also looked for Higgins Eye broodstock and found some displaying mussels and some natural surfaces providing habitat as well.
By: Megan Bradley
The remains of a mussel cage.
The newly constructed information kiosk in front of the Interpretive Center at Genoa NFH. Display of Hatchery information will greatly enhance visitor’s experience at GNFH and facilitate use of the walking trails and open spaces while the buildings remain closed. USFWS Photo.
It has been quite a struggle to provide an environmental education experience while visiting the hatchery during the current pandemic, never mind make improvements to visitor services. Due to the current COVID-19 pandemic the station’s culture buildings and Visitor Center have had to be closed to the public. However, the Friends of the Upper Miss, the hatchery’s grass roots support agency has taken on the challenge to make improvements to the hatchery’s visitor center and gift shop. These modifications are to improve visitor and staff safety once we are able to open up the buildings to visitors again. These include building attractive and functional polyethylene guards at visitor contact stations at the front desk and book store to reduce viral transmission. Hand disinfection stations were also added for further risk reduction.
Also included in the improvements this fall is a new visitor kiosk. The kiosk is located on the outside of the Visitors Center and is currently available to the public. It contains information put together by our former environmental education specialist Raena Parsons, and the kiosk was built by Friends Board Members Ken Visger and Ron Walley and the hatchery maintenance staff. It is out in the open air and available for visitors to peruse now as the hatchery grounds, pond area and nature trails are still open and available for people to use. It is hoped that someday soon the hatchery and its facilities will be fully open to everyone. In closing, it is safe to say that we are fortunate to have our Friends group, with these talented folks with diverse talents support our conservation mission.
By: Doug Aloisi
Poly guard installed on Visitor’s Center front desk. USFWS Photos.
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.