Biodiversity of freshwater mussels of the upper Sangamon River: Community Science in Action (2021-current)

A volunteer led effort to monitor freshwater mussels long-term in a central Illinois river was initiated in 2021. This work is a collaboration between community scientists in the Illinois RiverWatch Network and Upper Sangamon River Conservancy (USRC) and partners in research and education representing the National Great Rivers Research & Education Center, Illinois Natural History Survey, Missouri Botanical Garden, and Saint Louis Zoo. With support from the research and education team, community scientists with RiverWatch and the USRC implemented a mark-recapture study at 8 sites across the upper Sangamon River that will continue for 10 years. Results from the first two years include marking hundreds of mussels, capturing ~20 species, a genetic analysis of Pistolgrip Tritogonia verrucosa and Round Pigtoe Pleurobema sintoxia, and recording one live individual of the state endangered Spike Eurynia dilatata. Until 2022, live Spike had not been recorded in the basin in decades. Additionally, this project has produced a short film, mussel story map, and seminars for community events. The ability of this work to impact the long-term conservation of freshwater mussels will be enhanced by bringing the local community into the scientific process and engaging them as partners throughout our project.

Funded the first 2 years through a grant with the Living Earth Collaborative at Washington University in St. Louis. Currently pursuing other funding opportunities for our long-term objectives.


Distribution and relative abundance of Federally Listed mussels in the Vermilion River of Illinois and Indiana (2024-2025)

Twelve Federally-listed mussels are found in Illinois, and three of those are extant in the Vermilion River (Wabash River basin); both Northern Riffleshell Epioblasma rangiana and Clubshell Pleurobema clava are found only in the Vermilion River basin, and Rabbitsfoot Theliderma cylindrica is found only in the Ohio River and North Fork of the Vermilion River. A fourth species, the Salamander Mussel Simpsonaias ambigua, is under review by the U.S. Fish and Wildlife Service (USFWS) and its current status in this basin is uncertain. We will conduct a survey of Federally-listed mussels in the Vermilion River basin of Illinois and Indiana to provide robust and locally relevant evaluations of species distributions and relative abundances. Efforts from other projects listed below will help contribute to updating Salamander Mussel distributions in east central Illinois.

Funded by the Illinois Department of Natural Resources.


Investigating viable reproduction in freshwater mussels in the Vermilion River basin (2024-2025)

The US Fish and Wildlife Service recovery plans for Northern Riffleshell and Clubshell identify maintaining and restoring viable populations as a primary goal. Through this scope of work, monitoring will be resumed to assess persistence of relocated individuals and determine whether the translocated population is recruiting through the collection of juvenile individuals. Thus far, no formal assessment of recruitment or viable glochidia has occurred. Further, a sample of the resident fish population will be collected to confirm the presence of suitable host fish species. Host fish species will be sampled during mussel brooding timeframes to determine whether collected host fish have been infested with the respective mussel species’ glochidia. Collectively, these efforts are to determine whether the reintroduced populations have viable reproduction efforts.

Funded by the US Fish and Wildlife Service.


Regional Mussel Decline Study (2023-2025)

This project involves a collaborative effort between Minnesota Department of Natural Resources and Illinois Natural History Survey. The first component involves participation in a large-scale, cooperative project to examine causes of freshwater mussel declines in North America. This research will contribute to a larger collective effort with mussel experts in surrounding states’ carrying out a similar replicated study in cooperation with U.S. Forest Service (USFS), University of Kentucky, and American Rivers ( Funding allowed both states to implement several field sites for a juvenile mussel silo study, water and sediment analysis and mussel surveys for updating certain Species in Greatest Conservation Need.


The second component of this work is to use a combination of survey techniques including eDNA methodologies and targeted field sampling to explore Salamander Mussel and Mudpuppy distributions (see eDNA below). Additionally, because known populations of Salamander Mussel are reduced and presumably fragmented throughout its range, an assessment of current genetic variation and population structure is needed to identify evolutionarily significant units and prioritize conservation efforts to inform future plans to propagate and restore populations of this species where it is deemed appropriate.

We launched an effort “SimpsonaiasNation” in 2024 with regional mussel professionals to collect swabs from encountered Salamander Mussels across their range for the genetic analysis. This analysis will be conducted in partnership with Dr. Kentaro Inoue at the John G. Shedd Aquarium.

Funded by the US Fish and Wildlife Service Competitive State Wildlife Grants Program.


Environmental DNA (eDNA) monitoring of rare mussels, mudpuppies, and fishes (2019-current)

Presently, Salamander Mussels are listed as endangered in Illinois and as a species of concern, threatened, or endangered in most surrounding states. The USFWS is currently reviewing the species for listing under the United States Endangered Species Act of 1973 with a decision expected in fall 2024. Mudpuppies are listed as threatened in Illinois and a species of special concern in several surrounding states. Salamander Mussels and Mudpuppies are intricately linked as the Mudpuppy is the only host for the obligate parasitic larvae (glochidia) of Salamander Mussels. Given the complexities of finding live Salamander Mussels with any regularity, we initiated a proof of concept study to use eDNA as a survey tool to detect Salamander Mussels and their host’s presence or absence historical or (likely) extant locations in 2019 and 2020. Our goal in this pilot effort with the Salamander Mussel and Mudpuppy was to validate an eDNA survey protocol with an extremely rare mussel species and its elusive host.

Other eDNA work with these two species includes a seasonal detection study (2020-2021) and subsequent funding in a collaborative project with Minnesota Department of Natural Resources. We are conducting similar methods to what Isabel Porto-Hannes and the team at Fisheries and Oceans Canada recently published here and their assay. We are surveying and will be trapping in local east central Illinois watersheds with extant data for Salamander Mussels and mudpuppies in 2024-2025.

In northern Illinois, glacial lakes contain a unique fish fauna that includes several rare species. We collected samples at 8 sites and used an environmental DNA metabarcoding approach to determine occupancy of these rare fishes, along with compiling other fish community information, at each site. We modeled habitat and biotic characteristics to glacial lake fish occupancy using Hurdle models. Our results suggest an environmental DNA metabarcoding approach provided adequate information on rare species presence and community assemblages in urbanized glacial lake habitats in northeastern Illinois. 

Funded by the Illinois State Toll Highway Authority, the US Fish and Wildlife Service Competitive State Wildlife Grants Program, and the Philip W. Smith Memorial Fund Award (2021).


Kishwaukee River Mussel Population Study (2015-current)

In 2015, we began a long-term population dynamics and movement study of freshwater mussels in the Kishwaukee River in northern Illinois. Each year a team of biologists and land managers do an intensive search of a stretch of the Kishwaukee River along the I-90 Tollway.

The study is in its 10th year.

Funding from the Illinois State Toll Highway Authority supports this study.


Enigmatic invasive clams (2015-2018)

We observed a new introduction of an unknown Corbicula (basket clams) to the United States. Some of our research with this invasive species can be found here.

We had the privilege of hosting and advising an intern from the National Great Rivers Research & Education Center (NGRREC) 2017 Intern Program. Through this project, we mapped the spread, investigated geometric morphometrics, and genetics of the novel Corbicula species. A summary of results can be found here.

Descriptions of the 3 co-occurring Corbicula in Illinois can be found here.


Development of restoration criteria for freshwater mussel Species in Greatest Need of Conservation (2016-2020)

This project provided a detailed investigation into restoration options for specific mussel species in greatest conservation need. Optimal restoration options for a specific scenario–for example, stock host fish, restore habitat, improve water quality, or augment mussels, were investigated for Ellipse and Spike using a Bayesian Decision Network, a type of structured decision model. We determined limiting factors for both species present in northern Illinois (our focal area) and then subsequently built models to determine optimal restoration options in two stream systems. This project will be an initial step to provide guidance to state entities on the direction of restoration efforts for mussels in wadeable streams.

Funding from the US Fish and Wildlife Service State Wildlife Grant, Illinois Department of Natural Resources, and the Illinois Natural History Survey supported this study.


Defining expectations for mussel communities in Illinois wadeable streams (2013-2015)

This project updated knowledge of mussel Species in Greatest Conservation Need (SGCN). We reevaluated mussel species for listing as SGCN and provided an update of the statuses, distributions, and stresses to mussel SGCN appropriate for a revision of the Illinois Wildlife Action Plan (IWAP) and provided action items to include in the Streams Campaign. 

We completed distribution maps for each mussel species, and modeled potential species presence and historical (pre-settlement) distributions. Distribution maps and modeled expectations can assist with revisions or updates to conservation or recovery plans  for threatened and endangered species.

Funding from the US Fish and Wildlife Service State Wildlife Grant, Illinois Department of Natural Resources, and the Illinois Natural History Survey supported this study.


Investigating mussel communities in wadeable streams of Illinois (2009-2013)

Mussel community data was collected in wadeable streams throughout Illinois at existing basin monitoring sites used by the IL Department of Natural Resources and IL Environmental Protection Agency. These data added a mussel component to the existing datasets of water and sediment chemistry, instream habitat, and macroinvertebrate and fish indices, and provided baseline data for future monitoring of freshwater mussel populations on a local, regional, and watershed basis.

Statewide basin survey reports for freshwater mussels in Illinois can be found here.

Funding from the US Fish and Wildlife Service State Wildlife Grant, Illinois Department of Natural Resources, and the Illinois Natural History Survey supported this study.