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Sea Foam

Text by Vicki Osis and Bill Hanshumaker, marine education specialists, Sea Grant Extension, Oregon State University. © 2003 by Oregon State University.

This publication may be photocopied or reprinted in its entirety for noncommercial purposes.

ORESU-G-03-003

Graphics omitted from this version. A printable .pdf with all graphics is also available.

When it looks as if the beach or surf is littered with billows of soapsuds, the reason is not that someone has dumped a carload of detergent into the ocean. This common sight of spring and summer (and occasionally, brief periods in fall and winter) results from prolific reproduction of tiny single-celled plants of the sea called "phytoplankton."

Each individual is housed in a skeleton made of calcium or silica. Conditions of sun, temperature, and nutrients (such as nitrogen, phosphorous, silica, and calcium) stimulate rapid growth and reproduction. When the cycle has run its course, billions of individuals die.

Sea foam is created when waves or strong winds inject air into the dissolved organic matter in ocean water, forming bubbles. The organic matter, mostly made of dead microscopic plants, contains protein that gives the water enough surface tension to form bubbles. Surf and winds cause the mass to pile up in the familiar, sudslike masses.

If a microscope is available, you might want to take samples of foam to look at. The skeletons have a beauty that is seldom captured by drawings or photographs. Windrows of phytoplankton remains should tell you that the sea off our coast is producing tons of food for other creatures in the food web.

This publication was funded by the National Sea Grant College Program of the U.S. Department of CommerceÕs National Oceanic and Atmospheric Administration, under NOAA grant number NA16RG1039 (project number A/SGE-5), and by appropriations made by the Oregon State legislature. The views expressed herein do not necessarily reflect the views of any of those organizations.

Note: This is an accessible version of a document originally produced for the Web in .pdf format. While it contains all significant content of the original print document, it may omit layout and graphic elements which contribute to the look and feel of the original, and make the .pdf version more suitable for printing.