Best Estuarine

The Guadalquivir Marshes are an extensive system of seasonal wetlands located in the delta of the Guadalquivir River in Andalusia, southern Spain. The ecosystem includes brackish tidal marshes and lagoons, and it contains a significant portion of the Doñana National Park, a UNESCO World Heritage sit...

The Chesapeake Bay marshes comprise an extensive network of tidal wetlands located along the shores of the largest estuary in the United States. These salt and brackish marshes are biologically highly productive, providing essential habitat for migratory birds, fish, and blue crabs. The plant life w...

The Gulf of St. Lawrence is a large semi-enclosed sea in eastern Canada through which the St. Lawrence River reaches the Atlantic Ocean. It is bordered by Quebec, New Brunswick, Nova Scotia, Newfoundland and Labrador, and Prince Edward Island, and connects to the ocean through the Cabot Strait and t...

The Elkhorn Slough Marshes are a network of tidal wetlands located on the coast of Monterey Bay in California. As one of the largest remaining salt marshes in the state, the area provides a habitat for diverse wildlife, including sea otters and migratory birds. The site is protected and studied as p...

The Indo-Pacific humpback dolphin is a small, sociable cetacean found in coastal and estuarine waters of Southeast Asia and eastern Australia. It’s notable for its unique facial markings and complex social behavior. This species faces threats from habitat loss and fishing activities, making it vuln...

The Santoña, Victoria and Joyel Marshes form a 6,677-hectare estuarine wetland complex in Cantabria, Spain, designated a Ramsar site in 1994. This ecosystem consists of tidal mudflats, salt marshes, and beaches that serve as a critical habitat for migratory birds along the East Atlantic flyway. The...

The Odiel Marshes (Marismas del Odiel) is a protected wetland complex located at the mouths of the Odiel and Tinto rivers in Huelva province, southwestern Spain. This estuarine ecosystem covers approximately 7,185 hectares and was designated a UNESCO Biosphere Reserve in 1983 and a Ramsar Wetland of...

The Jiquilisco Bay wetlands form a large estuarine and coastal ecosystem in the department of Usulután on El Salvador's Pacific coast. The area includes mangrove forests, tidal channels, mudflats, islands, lagoons, and seasonally flooded land, and it is recognized as a wetland of international impor...

The Maugean skate is a critically endangered cartilaginous fish endemic to the brackish waters of Macquarie Harbour in Tasmania, Australia.

The Japanese mitten crab is an East Asian crab commonly identified as Eriocheir japonica and named for the dense hair covering its claws. It is catadromous: adults migrate from rivers toward brackish or marine water to reproduce, while juveniles move upstream into freshwater habitats. Its native dis...

The Solway Firth is a major estuary forming the border between England and Scotland, designated as a Ramsar site for its vital bird populations.

The Atlantic sea nettle, Chrysaora quinquecirrha, is a true jellyfish found in estuarine and coastal waters along the Atlantic and Gulf coasts of the United States. It has a bell-shaped body with trailing tentacles equipped with stinging cells used to capture zooplankton and other small prey. Season...

Plum Island Sound is a Massachusetts estuary bordered by the Great Marsh, where tidal creeks and salt marshes support fish, shellfish, and migratory birds.

Metapenaeus macleayi, an estuarine penaeid prawn endemic to eastern Australia, forms the basis of commercial fisheries in New South Wales and Queensland.

The Atlantic stingray (Hypanus sabinus) is a small stingray common in coastal and estuarine waters of the western Atlantic, notable as one of the few elasmobranch species tolerant of fully freshwater environments.

The mangrove whipray is a species of stingray in the family Dasyatidae, widely distributed across the Indo-Pacific region. Scientifically classified as Urogymnus granulatus, it is closely associated with mangrove estuaries, sandy flats, and shallow, turbid coastal waters. The ray is recognized by it...

The Korean mitten crab is a catadromous crustacean native to the freshwater river systems of the Korean Peninsula. Like other mitten crabs, it is distinguished by the dense patches of hair-like setae on its claws, which resemble mittens. Adults live in freshwater habitats but must migrate down to es...

The Estuary Stingray is a vulnerable species of whiptail stingray endemic to the coastal waters and estuaries of eastern Australia, originally described by James Douglas Ogilby in 1908.

The franciscana, or La Plata dolphin (Pontoporia blainvillei), is a small cetacean native to the southwestern Atlantic Ocean's coastal waters off Argentina, Uruguay, and Brazil. It is the only living member of the family Pontoporiidae and is physiologically adapted to the shallow, turbid waters of e...

A small leptomedusa native to the Black and Caspian seas, now invasive in numerous estuaries worldwide, including San Francisco Bay and Chesapeake Bay.

The Atlantic brief squid is a small loliginid squid species inhabiting the coastal waters of the western Atlantic Ocean, ranging from the Chesapeake Bay down to Brazil. It is notably one of the smallest squid species targeted by commercial fisheries, typically reaching a mantle length of only a few...

A brackish-water hydromedusa native to the Caspian–Black Sea region, recorded as an invasive species in San Francisco Bay, California, since the 1990s.

Metapenaeus brevicornis, a small penaeid prawn native to the Indo-West Pacific from India to Southeast Asia, is a commercially important species in Asian coastal fisheries.

Palaemonetes species are small, transparent shrimp native to freshwater and brackish habitats of North America, widely used as feeder animals and in ecological research.

A small hydromedusa first described from the brackish Lake Manzala in Egypt, since recorded in coastal lagoons and estuaries across multiple continents.

A freshwater hydromedusa native to South America, reported from rivers and lakes in Brazil and Argentina, belonging to the family Olindiidae.

The Guiana dolphin (Sotalia guianensis) is a coastal and estuarine dolphin of northern and eastern South America, named by the IWC in 2008.

The Purple Marsh Crab is a semi-terrestrial crustacean native to coastal regions of the Americas, recognized by its vividly colored purple carapace and preference for mangrove habitats.

The La Plata dolphin (Pontoporia blainvillei), or franciscana, is a small South American cetacean described in 1844 and tied to saltwater estuaries.