Marine, intertidal, mixed coarse, exposed, eulittoral

Mixed-coarse sediments are those where no one grain size occupies more than 70 percent of a stretch of beach. Instead, the beach is a mix (in variable quantities) of a few boulders, with cobble, gravel, and sand. Few such sites exist in highly wave-exposed areas because waves tend to 'sort' substrate types; this habitat type is much more common where sea stacks or other features reduce the wave energy reaching the shore. Drift algae may accumulate in these habitats, providing food and habitat for a variety of small organisms.