The Archaeological Study of Shell Middens

Maybe it is Just a Pile of Shells to You, but to an Archaeologist...

Shell Midden at Elands Bay (South Africa)
Shell Midden at Elands Bay (South Africa). John Atherton

One type of site that some archaeologists love to investigate is the shell midden or kitchen midden. A shell midden is a heap of clam, oyster, whelk, or mussel shells, obviously, but unlike other types of sites, it is the result of a clearly recognizable single-activity event. Other kinds of sites, such as camp sites, villages, farmsteads, and rockshelters, have their attractions, but a shell midden was created by and large for one purpose: dinner.

Diets and Shell Middens

Shell middens are found throughout the world, on coastlines, near lagoons and tidewater flats, along major rivers, in small streams, wherever some variety of shellfish is found. Although shell middens also date from pretty much all of prehistory, many shell middens date to the Late Archaic or (in the old world) Late Mesolithic periods.

The Late Archaic and European Mesolithic periods (around 4,000-10000 years ago, depending on where you're at in the world) were interesting times. People were still essentially hunter-gatherers, but by then were settling down, reducing their territories, focusing on a broader range of food and living resources. One often used way to diversify the diet was to depend on shellfish as a reasonably easy to obtain food source.

Of course, as Johnny Hart once said, “the bravest man I ever saw was the first to devour an oyster, raw”.

Studying Shell Middens

According to Glyn Daniel in his great history 150 Years of Archaeology, shell middens were first explicitly identified as archaeological in context (i.e., built by humans, not other animals) during the mid-nineteenth century in Denmark.

In 1843, the Royal Academy of Copenhagen led by archaeologist J.J. Worsaee, geologist Johann Georg Forchhammer, and zoologist Japetus Steenstrup proved that the shell heaps (called Kjoekken moedding in Danish) were, in fact, cultural deposits.

Archaeologists have studied shell middens for all kinds of reasons.

Studies have included

  • calculating how much dietary meat there is in a clam (only a few grams in comparison to the weight of the shell),
  • food processing methods (steamed, baked, dried),
  • archaeological processing methods (sampling strategies vs. counting the entire midden--which nobody in their right mind would do),
  • seasonality (what time of year and how often were clambakes held),
  • other purposes for the shell mounds (living areas, burial sites).

Not all shell middens are cultural; not all cultural shell middens are solely the remnants of a clambake. One of my favorite shell midden articles is Lynn Ceci’s 1984 paper in World Archaeology. Ceci described a series of weird donut-shaped shell middens, consisting of prehistoric pottery and artifacts and shell located on hillsides in New England. She figured out that they were in fact evidence of early EuroAmerican settlers reusing prehistoric shell deposits as fertilizer for apple orchards. The hole in the middle was where the apple tree stood!

Shell Middens through Time

The oldest shell middens in the world are about 140,000 years old, from the Middle Stone Age of South Africa, at sites like Blombos Cave. There are fairly recent shell middens in Australia, within the last couple hundred years anyway, and the most recent shell middens in the United States that I’m aware of date to the late 19th century and early 20th century AD, when the shell button industry was in progress along the Mississippi River.

You can still find heaps of freshwater mussel shells with several holes punched out of them lying along the bigger rivers of the American midwest. The industry nearly obliterated the freshwater mussel population until plastics and international trade put it out of business.

Shell Midden Archaeology

Sites: Stallings Island, USA; Vuelta Limon, Mexico; Plum Piece, Lesser Antilles; Da But, Vietnam; Capelinha (Brazil); Chilca, Peru; Natsushima, Japan, San Blas, Mexico, Blombos Cave, South Africa.

Cultures: Hoabinhian, Chantuto Phase, Jomon Tradition, Ertebølle-Ellerbeck culture, Howiesons Poort.

A Few Recent Studies

This article is part of the About.com Dictionary of Archaeology.

Ainis AF, Vellanoweth RL, Lapeña QG, and Thornber CS. 2014. Using non-dietary gastropods in coastal shell middens to infer kelp and seagrass harvesting and paleoenvironmental conditions.

Journal of Archaeological Science 49:343-360.

Biagi P. 2013. The shell middens of Las Bela coast and the Indus delta (Arabian Sea, Pakistan). Arabian Archaeology and Epigraphy 24(1):9-14.

Boivin N, and Fuller D. 2009. Shell Middens, Ships and Seeds: Exploring Coastal Subsistence, Maritime Trade and the Dispersal of Domesticates in and Around the Ancient Arabian Peninsula. Journal of World Prehistory 22(2):113-180.

Choy K, and Richards M. 2010. Isotopic evidence for diet in the Middle Chulmun period: a case study from the Tongsamdong shell midden, Korea. Archaeological and Anthropological Sciences 2(1):1-10.

Foster M, Mitchell D, Huckleberry G, Dettman D, and Adams K. 2012. Archaic Period Shell Middens, Sea-Level Fluctuation, and Seasonality: Archaeology along the Northern Gulf of California Littoral, Sonora, Mexico. American Antiquity 77(4):756-772.

Habu J, Matsui A, Yamamoto N, and Kanno T. 2011. Shell midden archaeology in Japan: Aquatic food acquisition and long-term change in the Jomon culture. Quaternary International 239(1-2):19-27.

Jerardino A. 2010. Large shell middens in Lamberts Bay, South Africa: a case of hunter-gatherer resource intensification. Journal of Archaeological Science 37(9):2291-2302.

Jerardino A, and Navarro R. 2002. Cape Rock Lobster (Jasus lalandii) Remains from South African West Coast Shell Middens: Preservational Factors and Possible Bias. Journal of Archaeological Science 29(9):993-999.

Saunders R, and Russo M. 2011. Coastal shell middens in Florida: A view from the Archaic period.

Quaternary International 239(1–2):38-50.

Virgin K. 2011. The SB-4-6 shell midden assemblage: a shell midden analysis from a late prehistoric village site at Pamua on Makira, southeast Solomon Islands [Honors]. Sydney, Australia: University of Sydney.