Is Nitrogen Pollution Changing the Food Chain in Long Island Sound?

By: Terry Backer and Julia Hyman Ellen Thomas, PhD, a professor at Yale and Wesleyan University, released findings showing that nitrogen pollution, and perhaps warming waters, may have changed the basis of the food chain in the Long Island Sound. Her research shows that a key shift in populations of microscopic algae has been occurring over the last several decades. This fundamental shift in the Sound’s menu of who eats what is likely to cause many familiar species’ populations to decrease. At the base of the Sound’s food chain are diatoms--single celled organisms that are found in fresh and salt water. Foraminifera, or forams, are also single celled organisms which adopt dazzling and intricate shapes with many looking like exotic microscopic seashells. Until recently the most common foram in the Sound was Elphidium excavatum, which eats diatoms. For 10,000 years diatoms were the most important microscopic algae suited to the Sound’s water temperatures and nutrient levels (including ...  more