Climate change contributes to the decline in off-reservation tribal harvest availability in the Great Lakes region

Climate change threatens the lifeways of Indigenous Peoples, impacting their rights to self-determination and sovereignty. In the Laurentian Great Lakes region, Indigenous communities have experienced harvest declines of wild rice (Ojibwemowin: Manoomin; Dakodiapi: Psiŋ; Latin: Zizania palustris), a sacred aquatic plant central to their culture. Here we analyzed 1985–2020 wild rice density and harvest data in relation to key climate variables. Our results indicate that wild rice stem density in the fall is higher in years that have (1) lower early-summer water levels due to decreased precipitation, and (2) longer lake-ice duration due to colder winter temperatures. Overall, wild rice available for tribal harvest off-reservation has declined regionally by ~5–7% annually—declines that are likely to continue due to anthropogenic climate change, specifically increased early-summer precipitation and warmer winters. This decline has infringed on Indigenous lifeways by reducing off-reservation tribal harvest, a right guaranteed by treaties with the U.S. government. Wild rice available for harvest outside of tribal reservations has declined by 5–7% annually, and the declines are likely to continue due to increasing early-summer precipitation and warmer winters, according to long-term monitoring data collected by tribal organizations.