The Site comprises the largest sand spit in Japan, a narrow fish-hook shaped peninsula (Notsuke-hanto), and a bay formed between the sand spit and the main island of Hokkaido (Notsuke-wan). It features salt marshes which are dominated by a dune grass species (Leymus mollis) and sand dunes which are covered with Japanese rose (Rosa rugosa) and a herb layer of multiple species including white clovers (Trifolium repens). The Site is regularly visited by more than 20,000 waterbirds, including whooper swan (Cygnus cygnus), brent goose (Branta bernicla) and greater scaup (Aythya marila). Notably, over 8,000 brent geese were recorded during the autumn season in 2018, making the Site the largest migratory stopover of the species in East Asia. Eelgrass (Zostera marina) beds span the bay, providing spawning and nursery grounds to fish and crustaceans. This repository of fishery resources enables the practice of traditional trawl net sailboat fishing which has continued since the Meiji era, in which the main catch is the Hokkai shrimp (Pandalus latirostris).