Although it's difficult to know for sure, foam from various sources can have different characteristics.
Natural foam usually:
- appears as light tan or brown in color, but may be white;
- smells earthy, fishy or has fresh cut grass odor;
- can occur over large areas and accumulate in large amounts, especially on windward shores, in coves and eddies; and
- dissipates fairly quickly, except when agitated (as in high wind conditions).
Unnatural foam from human activity usually:
- appears white in color;
- gives off a fragrant, perfumed or soapy odor; and
usually occurs over small area, localized near a source of discharge.