One way to predict how productive certain areas of the ocean will be for fishing is by observing images that show the distribution and concentration of chlorophyll. Coastal Zone Color Scanner (CZCS) images, gathered by satellite instruments, show different concentrations of chlorophyll in the ocean.

Chlorophyll is a plant pigment found in microscopic ocean plants called phytoplankton. Phytoplankton are the primary source of food for marine life. Microscopic animals called zooplankton feed on phytoplankton. Still larger animals, in turn, feed on zooplankton. Thus, the presence of phytoplankton often results in larger fish moving into an area for food.

  !   Examine the CZCS image and color code to interpret where the highest numbers of phytoplankton could be found.