Plants and Animals
Sagittunio nasutus Eastern pondmussel
Key Characteristics
The Eastern pondmussel is a medium to large (to 6 inches, average about 3 inches), elongate mussel with a thin but sturdy, greenish-yellow to brown shell, with narrow green rays sometimes visible. Identifying features include a bluntly pointed posterior end, straight dorsal and curved ventral margins, and a low, wide beak. The nacre varies in color from white to iridescent pinks and blues.
Status and Rank
US Status: No Status/Not Listed
State Status: E - Endangered (legally protected)
Global Rank: G3 - Vulnerable
State Rank: S2 - Imperiled
Occurrences
County | Number of Occurrences | Year Last Observed |
---|---|---|
Alcona | 1 | Historical |
Alger | 1 | 1940 |
Allegan | 1 | 2002 |
Arenac | 2 | 1932 |
Bay | 5 | 1926 |
Benzie | 2 | 1925 |
Cheboygan | 11 | 2019 |
Emmet | 8 | 2018 |
Huron | 3 | 1964 |
Iosco | 5 | 2000 |
Macomb | 4 | 1940 |
Monroe | 15 | 2014 |
Montcalm | 1 | 2015 |
Montmorency | 1 | 1925 |
Ogemaw | 1 | 1957 |
Oscoda | 1 | 2013 |
Presque Isle | 3 | 2005 |
Roscommon | 1 | 2015 |
Saginaw | 6 | 2010 |
St. Clair | 8 | 2016 |
St. Joseph | 1 | Historical |
Tuscola | 1 | Historical |
Wayne | 28 | 2019 |
Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.
Habitat
Preferring fine sand to mud substrates, the Eastern pondmussel inhabits lakes and ponds, as well as slackwater areas of canals, rivers and streams (Metcalfe-Smith and McGoldrick 2007).
Specific Habitat Needs
Sandy substrate needed in: Great lake, littoral, benthic; Great lake, pelagic, benthic; Inland lake, littoral, benthic; Inland lake, pelagic, benthic; Mainstem stream (3rd-4th order), pool.
Natural Community Types
- Great lake, littoral, benthic
- Great lake, pelagic, benthic
- Inland lake, littoral, benthic
- Inland lake, pelagic, benthic
- Mainstem stream (3rd-4th order), pool
- River (5th-6th order), pool
For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.
Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.
Management Recommendations
Maintaining habitat integrity is essential to the survival of the Eastern pondmussel, and mussels in general. Dredging, impoundments, construction and dam removal negatively affect this species. Where these activities occur, monitoring to assess impacts, and mitigation measures such as relocation of potentially affected specimens, should be carried out. Healthy populations of host fish are critical to the maturation and dispersal of glochidia, and should also be managed for. As unionid mussels have shown particular sensitiviy to pollutants such as ammonia (Wang et al. 2007), chlorine (Valenti et al 2006), and heavy metals (March et al. 2007, Valenti et al. 2005, Wang et al. 2007), high water quality standards must be met. The treatement of lake areas with herbicides and pesticides containing copper should be avoided where Eastern pondmussel is present. Non-point source pollution and altered stream hydrology should also be addressed to ensure the viability of unionid mussel populations. Zebra mussels attach to native mussels and restrict movement and feeding, eventually causing mortality. The extirpation of entire native mussel communities has often been the result (Schloesser et al. 1996). Preventing the spread of zebra mussel adults and larvae by cleaning boat hulls, trailers, scuba and fishing gear, is critical in maintaining Eastern pondmussel populations.
Active Period
Gravid from first week of August to fourth week of May
Survey Methods
Visual and tactile search using scuba or glass-bottom buckets. Tactile search (by hand) is especially important where water turbidity and pebbles/rocks make visual detection difficult. After identification, live mussels should be planted back into the substrate anterior end down. Surveys should not take place after heavy rains or during periods of high water as these conditions can make detection much more difficult. Methods of documenting survey effort include: searching a large measured area, e.g. 128m2; taking multiple quadrat samples; and recording search time (person hours). For all methods, at least some excavation of substrate (by hand, 5-10cm down) should be done to detect buried mussels. Searching a large measured area or timed searches are generally better for detecting rare species and generating a species list than quadrat sampling. These two methods allow more types of microhabitats and a larger area to be covered. Quadrat sampling is better suited for documenting changes in density and other statistical analyses at the site level (Strayer and Smith 2003).
Glass-bottom bucket less than waist deep water
Survey Period: From first week of June to first week of October
Time of Day: Daytime
SCUBA greater than waist deep water
Survey Period: From first week of June to first week of October
Time of Day: Daytime
References
Technical References
- COSEWIC. 2007. COSEWIC assessment and status report on the Eastern pondmussel Ligumia nasuta in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa, ON. 34pp.
- Grabarkiewicz, J. and W. Davis. 2008. An introduction to freshwater mussels as biological indicators. EPA-260-R-08-015. U.S. Environmental Protection Agency, Office of Environmental Information, Washington, DC.
- March, Ferrella A., F. James Dwyer, Tom Augspurger, Christopher G. Ingersoll, Ning Wang, and Christopher A. Mebane. 2007. An evaluation, of freshwater mussel toxicity data in the derivation of water quality guidance and standards for copper. Environmental Toxicology and Chemistry 23(10): 2006-74.
- Ortmann, A.E. 1919. Monograph of the naiades of Pennsylvania. Part III. Systematic account of the genera of the naiades. Annals of the Carnegie Museum 8:222-365.
- Scholesser, Don W., Thomas F. Nalepa, Gerald L. Mackie. 1996. Zebra Mussel Infestation of Unionid Bivalves (Unionidae) in North America. American Zoology 36:300-10.
- Valenti, T.W., D.S. Cherry, R.J. Currie, R.J. Neeves, J.W. Jones, R. Mair, and C.M. Kane. 2006. Chlorine toxicity to early like stages of freshwater mussels (Bivalvia: Unionidae). Environmental Toxicology and Chemistry 25(9):2512-18.
- Valenti, T.W., D.S. Cherry, R.J. Neves, and J. Schmerfeld. 2005. Acute and chronic toxicity of mercury to early life stages of the rainbow mussel, Villosa iris (Bivalvia: Unionidae). Environmental Toxicology and Chemistry 24(5):1242-6.
- Wang, N., C.G. Ingersoll, I.E. Greer, D.K. Hardesty, C.D. Ivey, J.L. Kunz, W.G. Brumbaugh, F.J. Dwyer, A.D. Robers, T. Augspurger, C.M. Cane, R.J. Neves, and M.C. Barnhart. 2007. Assessing contaminant sensitivity of early life stages of freshwater mussels (Unionidae): Chronic toxicity testing of juvenile mussels with copper and ammonia. Environmental Toxicology and Chemistry. 35pp.
- Watters, G. Thomas, Michael A. Hoggarth, and David H. Stansbery. 2009. The Freshwater Mussels of Ohio. The Ohio State University Press, Columbus. 421 pp.