Common Plants in a Marine Ecosystem

Marine vegetation provides the basis for all life in the ocean, taking solar energy and turning it into a source of food for other creatures. There are approximately 4,000 known species of marine plants, with a great diversity of form and ecological function. Many of these species are commonly found along beaches and coastal waters, providing a strong indicator of the health of the environment.

Found in temperate ocean water throughout the northern hemisphere, bladderwrack (Fucus vesiculosus) is one of the most common marine plants seen along beaches. It is a variety of brown algae (seaweed) that attaches to rocks via a hard, disc-shaped root. Foliage occurs in a wide range of sizes, from a few inches to several feet, and is rubbery with a glossy, olive-green coloration. It has several air sacs, or bladders, along the stem to help hold the foliage aloft in the water. Bladderwrack occurs mostly in intertidal areas where sunlight can reach it.

A common sight along beaches from Alaska to California, Turkish towel (Mazzaella affinis) is known for its rough, bumpy texture and deep red color. It grows predominantly in low intertidal and subtidal areas where it is periodically exposed to air. The plant grows with a single blade of foliage that tapers dramatically at each end, with a discoid root attachment at the base. Each blade grows to approximately 3 feet in length when mature.

Sea lettuce (Ulva fenestrata), a form of green algae, is among the most common marine plants in the world. It grows in a single large sheet with deeply lobed edges that are seen attached to rocks and underwater structures within the intertidal zone. It is bright green in color and nearly translucent, with small perforations along the leaves. Sea lettuce sometimes overruns its ecosystem, depleting oxygen from the water and killing local marine life.

Eelgrass (Zostera marina) is a common marine grass found in oceans around the world. It grows in sandy estuaries, either fully submerged or floating near the surface. The thin, ribbon-like foliage is perennial and bright green with subtle white markings. It produces tiny flowers that later develop into bladder-like fruit. The grass forms vast beds along the ocean floor, providing breeding and nesting grounds for fish and small crustaceans.

Feather boa kelp (Egregia menziesii) is a chocolate-brown to light olive-green-colored kelp found in intertidal regions from Alaska to Baja, California. It grows to 30 feet in length and is lined with hundreds of 3-inch-long leaflets along either side, as well as numerous floating bladders. Despite its strong root fasteners, feather boa kelp often breaks free and washes up on beaches where it is frequently seen.