A clam garden (k’yuu kudhlk’aat’iija in the Haida language, lux̌ʷxiwēys in the Kwak'wala language:2) is a traditional Indigenous management system used principally by Coast Salish peoples.:205 Clam gardens are a form of mariculture,:308 where First Nations peoples created an optimal habitat for clams by modifying the beach.:2 These clam gardens are a food source for both First Nations peoples and animals. They also provide food security as they are a food source that can be readily harvested when needed.:2
Clam gardens are found along the west coast of North America. Over 2,000 clam gardens have been identified on the coast of Alaska, British Columbia, Washington state and California.:7 Though most clam gardens are currently untended, restoration of sections of previously untended clam gardens are occurring in Fulford Harbour on Salt Spring Island and on Russell Island located in the Gulf Islands National Park Reserve.
Once a location was chosen by an individual or a group of First Nations peoples, clam garden construction began with the creation of a boulder or rock wall on the chosen enclosed beach. Strong individuals would roll large boulders down to the lowest tideline on the beach, thus creating a rock wall.:207 The rising tide brings sediment over the rock walls, where it becomes trapped in the clam garden.:207 The rock wall is low enough that it allows the clam garden to be submerged at high tide, but tall enough that the beach is exposed for harvesting during low tide.:207
Due to weather and the movement of tides, rock walls require continual maintenance.:207 Historically, clam gardens were regularly tended by First Nations individuals regularly moving rocks from inside the clam gardens onto the rock wall.:207 Both archeological evidence and traditional knowledge assert that boulder walls were built up over time and continually maintained.:207 Individuals continually added new rocks at the top of the boulder wall, presumably by First Nations peoples when they were harvesting clams.:207:8
The accumulation of sediment trapped by the boulder wall creates a flatter beach, which is an optimal growing habitat for clams.:2 This sediment has an optimal density for clam growth, free from fine clay and silt particles that are washed away by the high tide.:207
The density of the sediment was also due to the process of aerating the sand while clams were harvested. Many clam gardens also have a high amount of gravel and shell hash, which aid in aerating the sand.:8:6 This density allows for freer movement of clams, in addition to easier removal of clams from the sediment.:204
Clam gardens are an ideal habitat for many animals. The modified beach attracts growth of many clams, notably: butter, littleneck, cockle and horse clams.:204:3 Animals such as barnacles, snails, crabs, eels, mussels, and sea cucumbers also live in clam gardens.:208 Other animals such as ghost shrimp and worms are found buried in the loose sediment.
Clam gardens were a food source for many Coast Salish peoples, and provided food security to many diverse First Nation communities. This was due to the abundance of clams that could be easily harvested and were readily accessible.:202:205 Women and children were the primary group tasked with harvesting clams at low tide, though everyone in the community could participate.:308:2 Once harvested, families could consume the clams immediately or smoke them to be preserved for the winter.:205 Resources of clams, either smoked or harvested from the gardens were important since they served as sustenance when other foods were scarce.:5 Some nations, such as the Kwakwaka’wakw nation, traditionally harvested clams from October to early March so as to avoid the red tide.:204:11
Clam gardens were not exclusive to humans but also served as a protein-rich food source for animals, such as bears, during the spring or summer. Animals such as raccoons, mink, river otters, bears, sea ducks, and geese also feed in clam gardens.:208
Traditional clam harvesting also allowed for intergenerational knowledge transmission, with elders passing down knowledge about clam gardens to the next generation.:308 Clam gardens were similar to an outdoor classroom, where traditional knowledge, language and cultural practices could be learned by the community.:308
Each nation has specific protocols and governance systems around land management, and many access areas are family based.:11 For clam gardens, families often asserted ownership by regularly tending to the beach and maintaining the rock wall.:9 These clam gardens were then handed down to the next generation. Historically, unmanaged clam gardens could be harvested by anyone in the community.:8 Families could claim ownership by building their own clam garden on an undeveloped beach area in their traditional territory.:5
The exact age of the origin of clam gardening is unknown. In present day, scholars argue that accurately dating clam gardens is difficult due to the rock wall being submerged, in addition to rising sea levels.
Archeologists are studying the ages of clam gardens using methods such as optically stimulated luminescence and radiocarbon dating on the rock wall.:12 Scholars are using both methods to gain a better understanding of the age of clam gardens.:12 The results are different depending on the sample as evidence suggests walls were built up by communities over time.:12 Dating results suggest that clam gardens range from 1000 to 1700 years old,:12 whereas other samples indicate that they are around 3000 years old.
Conversely, many First Nations peoples have a different perspective of clam garden creation. For example, Clan Chief Adam Dick, Kwaxsistalla of the Kwakwaka'wakw nation, states that clam gardens have been around “since the beginning of time.”:202 Tom Sewid, a Native Watchman of the Mamalilikulla-Qwe'Qwa'Sot'Em nation, states that his ancestors have maintained clam gardens over "thousands of years" citing clam gardens as title to his traditional lands.
- "Gardens of plenty: K'yuu ḴudhlḴ'aat'iija (clam gardens) grow clams four times faster". Council of the Haida Nation. 25 January 2016. Archived from the original on 2 November 2018. Retrieved 2 November 2018.
- Turner, Nancy; Recalma‐Clutesi, Kim; Duer, Douglas (26 March 2013). "Back to the Clam Gardens" (PDF). EcoTrust. Archived from the original (PDF) on 2 November 2018. Retrieved 2 November 2018.
- Sewid, Tom, Elizaga, Andrew (18 August 2013). "Mysteries of Ancient Clam Gardens". Youtube. 2:35, 4:48. Archived from the original on 2 November 2018. Retrieved 2 November 2018.
- Deur, Douglas; Dick, Adam; Recalma-Clutesi, Kim; Turner, Nancy J. (10 April 2015). "Kwakwaka'wakw "Clam Gardens"". Human Ecology. 43 (2). 205. doi:10.1007/s10745-015-9743-3. ISSN 0300-7839.
- Augustine, Skye; Dearden, Philip (2014-03-07). "Changing paradigms in marine and coastal conservation: A case study of clam gardens in the Southern Gulf Islands, Canada". The Canadian Geographer. 58 (3): 305–314. doi:10.1111/cag.12084. ISSN 0008-3658.
- Groesbeck, Amy S.; Rowell, Kirsten; Lepofsky, Dana; Salomon, Anne K. (2014-03-11). "Ancient Clam Gardens Increased Shellfish Production: Adaptive Strategies from the Past Can Inform Food Security Today". PLoS ONE. 9 (3): e91235. doi:10.1371/journal.pone.0091235. ISSN 1932-6203. PMC 3949788. PMID 24618748.
- Thomson, Jimmy (5 October 2015). "Clam Gardens Are Cultivating a New Look at Ancient Land Use". Hakai Institute. Paragraph 11. Archived from the original on 2 November 2018. Retrieved 2 November 2018.
- Snively, Gloria, Williams, Wanosts'a7 Lorna (2017). "Knowing Home: Braiding Indigenous Science with Western Science, Book 1". BC Campus Open Ed. Ancient Clam Gardens. Archived from the original on 2 November 2018. Retrieved 2 November 2018.CS1 maint: multiple names: authors list (link)
- Britten, Liam (4 January 2017). "Gulf Islands seeing return of traditional First Nations clam gardens". CBC. Paragraph 5. Retrieved 2 November 2018.
- Petrescu, Sarah (2 July 2017). "Uncovering ancient secrets in a First Nations clam garden". The Times Colonist. Paragraph 10. Retrieved 2 November 2018.
- Neudorf, Christina M.; Smith, Nicole; Lepofsky, Dana; Toniello, Ginevra; Lian, Olav B. (9 February 2017). "Between a rock and a soft place: Using optical ages to date ancient clam gardens on the Pacific Northwest". PLOS ONE. 12 (2): e0171775. doi:10.1371/journal.pone.0171775. ISSN 1932-6203. PMC 5300257. PMID 28182645.
- Lepofsky, Dana; Caldwell, Megan (2013). "Indigenous marine resource management on the Northwest Coast of North America". Ecological Processes. 2 (1): 12. doi:10.1186/2192-1709-2-12. ISSN 2192-1709.
- Jackley, Julia; Gardner, Lindsay; Djunaedi, Audrey F.; Salomon, Anne K. (2016). "Ancient clam gardens, traditional management portfolios, and the resilience of coupled human-ocean systems". Ecology and Society. 21 (4). doi:10.5751/es-08747-210420. ISSN 1708-3087.