Marine environments encompass a vast array of geological and ecological systems that are intricately intertwined with the saltwater of the world's oceans. These environments play a crucial role in supporting biodiversity and providing essential ecosystem services. Important marine ecosystems include exposed and protected coastlines, mangrove swamps, tidal salt marshes, kelp beds, lagoons, and coral reefs.
The coastlines themselves, whether rocky or made up of unconsolidated sediment, create varied environments with exposed cliffs, tide pools, and sheltered beaches, each supporting a unique array of life.
Mangrove swamps, typically found along tropical and subtropical coastlines, consist of salt-tolerant trees and shrubs that provide vital coastal protection from erosion while serving as nurseries for fish and other marine life. Tidal salt marshes, common along temperate coastlines, are flooded and drained by tidal waters, and are home to grasses and other plants that stabilize sediments and support a wide range of wildlife, including birds, fish, and invertebrates.
Kelp beds, primarily found in colder, nutrient-rich waters, are underwater forests of large brown algae that provide shelter and food for a variety of marine organisms, from sea otters to fish and invertebrates. Lagoons, often situated between a barrier island and the mainland, offer calm, shallow waters that support diverse species of fish, mollusks, and birds.
Coral reefs, found in warmer tropical seas, are some of the most biodiverse ecosystems on the planet, providing homes for coral species, fish, crustaceans, and a host of other marine life. These marine environments are essential for the health of our planet, providing food, coastal protection, and recreational opportunities while helping regulate the Earth's climate and carbon cycles.
There are National Natural Landmarks designated for their marine environments nationwide that illustrate the beauty and diversity of these ecosystems. Some of these include:
- Le’ala Shoreline, AS
- Bogoslof Island, AK
- Simeonof National Wildlife Refuge, AK
- Walrus Islands, AK
- Año Nuevo Point and Island, CA
- Point Lobos State Reserve, CA
- Pygmy Forest, CA
- Lignumvitae Key, FL
- Wassaw Island, GA
- Muskeget Island, MA
- Long Beach, Orient State Park, NY
- Bear Island, NC
- Smith Island, NC
- Mona and Monito Islands, PR
- Bayside Resaca Area, TX
- Virginia Coast Reserve, VA
- Lagoon Point, VI
- Salt River Bay, VI
- Sandy Point, VI
- Point of Arches, WA
Last updated: April 10, 2025