Yes, beavers are considered a foundation species.
Beavers are skilled ecosystem engineers. By building dams, they create ponds and wetlands that significantly alter the landscape. These habitats support a wide variety of species, including fish, amphibians, birds, and mammals, increasing biodiversity.
Beaver dams also help regulate water flow, reduce erosion, improve water quality, and support nutrient cycling by trapping nutrients and sediment.
Because beavers have a large and often disproportionate impact on the structure and function of their ecosystems, they are classified as foundation species.