Edmonds Marsh is one of the few urban saltwater estuaries remaining in the Puget Sound area. Before settlement this salt marsh occupied nearly 40 acres of barrier estuary and marsh complex, a rare geologic and biologically rich coastal ecosytem. Development reduced the marsh to its present area of 22.5 acres, which is now being restored and preserved for wildlife habitat, water quality and public enjoyment.

This ecologically unique wildlife sanctuary is habitat for over 225 species of resident and migratory birds. Great Blue Herons foraging are frequently observed from bird-viewing areas on an interpretive walkway along the north side of the marsh. A heron nesting colony is located in the trees bordering the south side of the marsh. Cattails (typha latifolia) provide food and habitat for many marsh animals including blackbirds, ducks, muskrats and wrens.