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Earth and Ecosystem Sciences

Mollusk Sampling in Large Connecting Rivers of the Laurentian Great Lakes

Freshwater mussels (unionids) are the most imperiled group of organisms in North America.

    • 70% of native species are either extinct or vulnerable to extinction (Haag 2012).

Dreissenid fouling of unionids is a primary cause of mortality in the Great Lakes watersheds.

    • Interferes with unionid feeding, respiration, locomotion, and reproduction (Schloesser et al. 1998; 2006; Lucy et al. 2014).

Little information is known on snail distributions throughout North America.

    • Snail surveys for the St. Clair and Detroit River System (SCDRS) have not been previously reported.

A new hope?

    • Large unionid refuge discovered and documented in St. Clair River delta (Zanatta et al. 2002, McGoldrick et al. 2009).

Objectives of this study:

    • Determine species richness and relative abundance of unionids remaining in the SCDRS.
    • Determine densities and community data for native and invasive snails in the SCDRS.
    • Determine densities of Quagga and Zebra mussels (collectively dreissenids) throughout the SCDRS.

Introduction

Site Selection

Survey Methods

Detroit River

60 sites were chosen throughout the Detroit River:

    • 20 sites were historically surveyed in the 1980s and/or 1990s.
    • 10 sites were chosen as potential refuges for unionid mussels based on expert knowledge of refuges.
    • 30 sites were randomly selected with equal representation between upriver and downriver sections.

After surveying the Detroit River, a unionid species distribution model was created using:

    • MaxEnt
    • Live unionid sites from the Detroit River.

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St. Clair River

76 sites were chosen throughout the St. Clair River

    • 11 sites were chosen based on a unionid species distribution model created from the Detroit River data.
    • 20 sites were historically surveyed in the 1990’s.
    • 8 sites were chosen as potential refuges for unionid mussels based on expert knowledge of refuges.
    • 37 sites were randomly selected (15 sites upriver and 22 sites downriver).

Unionids

Three 10-minute dives were performed by 2 divers at each site (1 person-hour time search).

    • Divers brought to the surface all live unionids and unionid shells for identification to species and quantification (Mulcrone & Rathbun 2020).

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Gastropods and Dreissenids

Six sediment samples were collected by petite PONAR at each site.

    • Sediment samples were sieved using water and 1 mm and 0.5 mm sieves.

Snails and dreissenids were identified to species and quantified.

    • Dreissenids were identified as either live or shell. Dreissenids categorized as alive at the time of PONAR collection had the following characteristics:
      • Intact hinge, intact periostracum, and/or tissue present.

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Abiotic Measurements

At each site we measured:

    • Surface water temperature, Secchi depth, and water column depth.

Additionally, divers estimated visibility, water velocity, dreissenid presence, sediment composition, and macrophyte coverage.

Figure 1. Summer 2019 sampling sites for the Detroit River (n = number of sites).

Figure 2. Summer 2021 sampling sites for the St. Clair River (n = number of sites).

Results

Acknowledgements

Unionids

  • In the Detroit River, 220 live unionids (12 species) were found among 5 sites (Figure 1).
  • In the St. Clair River, 14 live unionids (9 species) were found among 7 sites (Figure 2).

Dreissenids

Detroit River:

    • 308 ± 155 live dreissenids m-2
    • 84% Quagga Mussels

St. Clair River:

    • 489 ± 152 live dreissenids m-2
    • 99% Quagga Mussels

Snails

19 snail species were found in the SCDRS:

    • Snail presence was recorded at 98% (55/56) of Detroit River sites and 100% (51/51) St. Clair River sites.

Funding for this project was provided by the U.S. Fish and Wildlife Great Lakes Fish and Wildlife Restoration Act and the Cooperative Institute for Great Lakes Research. This research is supported by the EES doctoral program and IGLR at Central Michigan University. Special thanks to Michigan DNR divers P. O’Neil & K. Snyder; CMU divers K. Cushway, S. LaValley, N. Ring & N. Trombley; and ECCC divers C. Duggan, B. Gray, A. Morden, C. Treen, C. Weavers & C. Yonch. Special thanks to DFO (M. Goguen, K. McNichols-O’Rourke, M. Dolan, L. Dutheil, B. Foucault, E. Maclennan-Nobrega, K. Smith, S. Turner & K. Zammit), Michigan DNR (D. Clapp, J. Francis, E. Plant, D. Tar, S. Thomas, B. Utrup, T. Wills, B. Yonker), USGS (R. Debruyn, K. Keretz & E. Roseman), NOAA (A. Elgin), USFW (J. Boase), and CMU student researchers (L. Daniels, M. Layer, A. Rittmaier, E. Smrcka, J. Sokol, H. Torolski & J. Willsie).

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References

Lucy et al. 2014. Quagga and Zebra Mussels: Biology, Impacts, and Control 623-642.

Haag. 2012. North American Freshwater Mussels: Natural History, Ecology, and Conservation 316-390.

McGoldrick et al. 2009. Journal of Great Lakes Research 35:137-146.

Mulcrone & Rathbun. 2020. Michigan Dept. of Natural Resources. 78 p.

Schloesser et al. 1998. American Midland Naturalist 140:299-313.

Schloesser et al. 2006. American Midland Naturalist 155:307-320.

Zanatta et al. 2002. Journal of Great Lakes Research 28:479-489.

Historically Surveyed

Expert Selected

Randomly Selected

Crystal Bay (n=1)

  • 5 live mussels
  • 1 species (Giant Floater)

Elba Island (Grosse Ile, n=1)

  • 1 live mussel
  • 1 species (Plain Pocketbook)

Near Lake Erie (n=1)

  • 2 live mussels
  • 2 species (Threeridge & Pink Heelsplitter)

Downstream of River Canard (n=2)

  • 212 live mussels
  • 10 species
  • Most common species:

Fragile Papershell

Leptodea fragilis

Mapleleaf

Quadrula quadrula

Historically Surveyed

Expert Selected

Randomly Selected

Model Selected

Downstream of Black River (n=2)

  • 2 live mussels
  • 2 species (Fluted-Shell & Threeridge)

Downstream of Black River (n=1)

  • 3 live mussels
  • 2 species (Mucket & Fat Mucket)

Middle Ground Reef (n=2)

  • 3 live mussels
  • 2 species (Plain Pocketbook & Threeridge)

South Channel (n=1)

  • 2 live mussels
  • 2 species (Fat Mucket & Pink Heelsplitter)

North Channel (n=1)

  • 4 live mussels
  • 3 species (Eastern Pondmussel, Creeper, & Giant Floater)

U.S.

Canada

Shay S. Keretz1, Daelyn A. Woolnough1, Todd J. Morris2, Gabrielle E. Sanfilippo1, Dylan T. Powell1, Nichelle M. VanTassel1, Aaliyah D. Wright1, and David T. Zanatta1

1Department of Biology and Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, Michigan, USA 48859 2Great Lakes Laboratory for Fisheries and Aquatic Sciences, Fisheries and Oceans Canada, Burlington, Ontario, Canada L7S 1A1

INSTITUTE FOR

GREAT LAKES

RESEARCH

CENTRAL MICHIGAN UNIVERSITY

Objectives