Tennessee Wildlife Resource Agency partnership with Dale Hollow NFH
Dale Hollow National Fish Hatchery has active mussel recovery partnerships with Tennessee Wildlife Resource Agency (TWRA) and Ecological Services (ES. The hatchery provides a food abundant healthy growing site on the lake to grow mussels closer to adult size before they are planted out into the waterways being supported by the species specific projects. The three recovery teams have our individual roles, but there is a lot of trust and cooperation that has been developed over the years, so efforts are always collaborative even when stations are performing independent duties. The majority of the hatchery mussel rearing labor involves boat house upkeep, weekly cage brushing, and providing as much support as possible to develop and grow the partnerships so we can continue to try to maintain breeding genetic diversity and annual population output.
TWRA Cumberland River Aquatic Center current mussel rearing project goals are to research and build capacity to rear listed species, even if nobody else has had success with captive breeding. They experiment with different feeds, water quality, host fish, and even in-vitro fish blood/plasma zygote outputs. Every year they've made more headway and are developing a mountain of information that is becoming the core driver behind target species captive production. Since the state is responsible for genetics, the station mostly just supplies logistics and the grow-out location to TWRA's flexible and evolving species project scopes. The TWRA C-RAC team is led by Senior Scientist Dan Hua with staff, interns, and volunteer. The following species have been planted/harvested/inventoried this year. Dan Hua’s breeding and rearing objectives with Dale Hollow National Fish Hatchery right now is to focus on high need species, species whose rearing science needs the most study, propagation of mussels not reared by other programs, and continued breeding refinement strategies with both host infestation and in-vitro fertilization using fish blood media.
| Scientific name | Common name |
| Dromus dromas* | Dromedary pearlymussel |
| Epioblasma ahlstedti* | Duck River dartersnapper |
| Epioblasma obliquata* | Catspaw |
| Hemistena lata* | Cracking pearlymussel |
| Lampsilis abrupta* | Pink mucket |
| Lampsilis fasciola | Wavy-rayed lampmussel |
| Lemiox rimosus* | Birdwing pearlymussel |
| Medionidus conradicus^ | Cumberland moccasinshell |
| Obovaria subrotunda# | Round hickorynut |
| Plethobasus cyphyus* | Sheepnose |
| Pleurobema plenum* | Rough pigtoe |
| Ptychobranchus subtentus* | Fluted kidneyshell |
| Toxolasma cylindrellus* | Pale lilliput |
| *. Endangered species | |
| ^ Proposed Endangered | |
| # Threatened |
Of the hatchery's 50 cages, 42 of them need the outer mesh replaced. The old metal mesh did great for years but is rusting and cutting everyone that works with it now. Some aluminum mesh was located and tested satisfactory as replacement material - the new mesh is not as stiff/sharp so even the default seams will pose much less handling hazard. TWRA is really going above and beyond with their science and scope of their mussel rearing already, plus now they are also going to help us supply the maintenance work to start overhauling the cage material. We have more future cage designs to play with eventually, but we are going to focus on the rehab effort to update the current rearing hardware to safe working status.
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Ecological Services partnership with Dale Hollow NFH
The Hatchery's partnership with Ecological Services (ES) is still mostly in the planning stage, with implementation possible later in 2024 or early in 2025.
A collaborative effort to focus on the stratification and replication of surviving mussels into redundant thriving and breeding locations of target mussel species in Wolf River. Single, geographically vulnerable mussel populations have been identified and hatchery grow-out in the connected Dale Hollow reservoir water body is projected as viable tool capable of assisting the dissemination of target species further into endemic waters.
Target Wolf River Species for Augmentation:
- Fluted Kidneyshell
- Cumberland Moccansinshell
These species have identified footprints on the Wolf River, but are facing risks from the limited spread along singular stretches of water. Hatchery involvement for 2024 will include the program tracking and facilitation of wild intake, holding, and progeny rearing. As a collaborative effort the genetics will be spread further along the Wolf River to increase population redundancy, increase wild reproduction via stocking, and research captive rearing best practices.
At the end of the first year the goals are to develop protocols with timeline for the intake of wild genetics, host fish, and mussel progeny growth phase, track wild population data from ES project oversight, and report on comprehensive restoration efforts, test feed for captive reared intensive culture specimen, and start to develop protocols and holding units for quarantine host fish. We have a small grant proposal for interested conservation groups to consider funding a new working platform idea for the boat-house that would raise and lower multiple cages on decking using some low cost winches - this could increase a lot of the mussel inventory work efficiency and would only cost the price of some base materials.
For partner, volunteer, and science questions, please email thomas_reeves@fws.gov
