Sea Lettuce (Ulva lactuca)

Description: Sea lettuce—a type of green algae—is one of the most commonly-found species of seaweed, typically seen in tide pools attached to rocks. Sea lettuce is what one may imagine when they think of a typical seaweed: it grows in thin strips, it averages about 30 centimeters (almost 1 foot) in length, and its color varies in shades of green. Sometimes it’s more pale, but often it is a vivid, bright green.

Habitat: Its geographic range spans from northern Alaska down to California along North America’s Pacific Coast. It’s also found along the coastlines of China, Japan, Korea, and Russia.  

Tide Pool Tidbits:

• Sea lettuce is edible and can either be eaten fresh or dried. Other human uses of sea lettuce include using it in soaps, hair care products, and facial creams since it can increase hair growth and keep skin revitalized, plump, and youthful.

• Like other types of algae, sea lettuce can grow at rapid rates when exposed to high nutrient levels from things such as fertilizer runoff near agricultural areas. After these massive sea lettuce blooms occur, the seaweed eventually dies. What one may not initially expect is that the process of the sea lettuce rotting consumes almost all of the available oxygen in an area. This leads to hypoxic conditions known as “dead zones” which can cause other marine creatures to suffocate and die if they cannot escape that area.

Reference: Central Coast Biodiversity