Fish (IMAGE) Cary Institute of Ecosystem Studies Caption Nitrogen is an essential component of protein; fish store nitrogen in their biomass when they feed in coastal waters. Credit Kieran Kelleher, World Bank. Usage Restrictions In print and internet outreach License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.