Creature Feature: Tidewater mucket mussel

Turkey, stuffing, mashed potatoes, and pumpkin pie . . . all will appear on many tables this coming Thursday for Thanksgiving, a national holiday in the United States commemorating the fabled autumnal harvest meal at Plymouth, Massachusetts in 1621. While the Thanksgiving myth mis-portrays the history of the Wampanoag people and the Pilgrims, how accurately do our beloved holiday foods reflect what was eaten by people of the Northeast at the time? If there had been a fall feast at Plymouth in the early 1600s, it probably would have included staples of the region like turkey and corn along with another food that is much less common at modern-day Thanksgiving meals: mussels^1,2!

The tidewater mucket (shells pictured above) is a species of mussel found along the Northeast coast of the United States and was likely an important diet staple of people in that region in the 1600s. Image from the National Biodiversity Center [Source].

Historical records indicate that mussels were abundant and easily harvested in the New England area, thus making mussels, and shellfish in general, a key portion of people’s diet². It is unknown exactly which mussel species were eaten, but a likely candidate is the tidewater mucket, Leptodea ochracea. Tidewater muckets can be found along the Atlantic coast from Nova Scotia to Georgia, including Southeastern Massachusetts and Cape Cod (the location of Plymouth Colony)³.

**This map highlights the region near Plymouth Colony where populations of tidewater muckets were historically and currently found. Image edited by Nicole Korzeniecki [Source].**

Tidewater muckets are aquatic, shelled animals. The adults are sedentary and partially burrow themselves in sediments at the bottom of rivers, streams, estuaries, ponds, and canals. They can thrive in a variety of substrates such as gravel, sand, silt, cobble, and sometimes clay^4,5. Most of their lives are spent in one place, however, the larval (juvenile) stage of the tidewater mucket involves a stretch of secondhand travel. During the spring, adult tidewater muckets produce glochidia, or parasitic larvae, that are released into the water and attach to the fins or gills of a host fish. Once attached, the glochidia become passengers as the host fish swims away, carrying the juvenile mussels to new locations where they can settle. Not all fish species can serve as hosts to glochidium, and the only confirmed host for the tidewater mucket is the white perch (Morone americana)⁶.

This image depicts the life cycle of a tidewater mucket and similar mussels. Starting on the bottom, a male mussel releases sperm that will fertilize the eggs released by female mussels. The larva that develops from these fertilized eggs then attaches to the gills of host fish (top left). When ready, juvenile mussels will detach from the fish’s gills and settle (top right), eventually becoming adult mussels. Image by Kim Lindgren [Source].

The tidewater mucket is classified as a species of “special concern” in Massachusetts, and it is considered “at risk” in Nova Scotia and “threatened” in Connecticut, Maine, and New Jersey³. Due to their sedentary lifestyle, adult tidewater muckets are vulnerable to environmental degradation, sedimentation, nutrient enrichment, pollution, invasive species, and consequences of urbanization³. Surveys of tidewater mucket populations throughout their range allow for monitoring and habitat assessment and aid communities in developing conservation and restoration programs targeted to those areas³.

Mussels, including tidewater muckets, are some of the most important internal filter feeders. This means that by using internal structures, they filter out particles like phytoplankton (tiny aquatic plants) and bacteria directly from the water and consume them⁷. Through this feeding mechanism, mussels improve the water quality and clarity of their aquatic environment⁷. Additionally, mussels are important members of marine and freshwater food webs because they consume primary producers like phytoplankton. Therefore, it is important to protect these animals in order to preserve the water quality and health of aquatic ecosystems.

**Most people see mussels out of the water with their shells closed. However, underwater, mussels keep their shells open to allow water to filter through their feeding structures [Source].**

The next time mussels appear on your table, take a moment to appreciate all they do for our aquatic ecosystems and diets—both now and nearly 400 years ago!

Nicole W. Korzeniecki is a graduate student in the Animal Behavior Graduate Group at UC Davis. She’s interested in the dynamics of social insect colonies, specifically in host-microbiome interactions, collective decision-making, and the self-organization of complex behaviors.

References

Gambino, Megan. “What was on the Menu at the First Thanksgiving?” Smithsonianmag.com, 21 Nov. 2011, https://www.smithsonianmag.com/history/what-was-on-the-menu-at-the-first-thanksgiving-511554/.
“First Thanksgiving Meal.” History.com, A&E Television Networks, 18 Nov. 2011, http://www.history.com/topics/thanksgiving/first-thanksgiving-meal.
“Tidewater Mucket Leptodea ochracea.” Natural Heritage & Endangered Species Program, Massachusetts Division of Fisheries & Wildlife, https://www.mass.gov/files/documents/2016/08/no/leptodea-ochracea.pdf
“Leptodea ochracea Tidewater Mucket.” NatureServe Explorer, https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.114703/Leptodea_ochracea
Ortmann, A. E. (1919). A Monograph on the Naides of Pennsylvania Part 3, Systematic Account of the Genera and Species. Mem. Carnegie Mus. Pittsburgh, Pennsylvania.
Wick, P. C. & Huryn, A. D. (2003). PL 31. Fish hosts and population demographics of Lampsilis cariosa and Leptodea ochracea (Unionidae) in Maine. Meeting Program and Abstracts of the 3rd Biennial Symposium of the Freshwater Mollusk Conservation Society, March 16-19, 2003, Durham, North Carolina. 56 pp.
“Filter Feeders.” Newport Bay Conservancy, https://newportbay.org/wildlife/marine-life/filter-feeders/.

For more information on the fallacies of Thanksgiving related to colonialism and Native American people, check out this episode from All My Relations Podcast.

Edited by Jessica Schaefer