Some , marine species are known to science—about 15 percent of all the species identified on the planet. But the sea is so vast that a million or more as yet unknown species may live in its waters. Most of these aquatic species are tied together through the food web. The foundation of the sea's food chain is largely invisible.
Marine food web
Examples of Marine Food Chains | Sciencing
Compared to terrestrial environments, marine environments have biomass pyramids which are inverted at the base. In particular, the biomass of consumers copepods, krill, shrimp, forage fish is larger than the biomass of primary producers. This happens because the ocean's primary producers are tiny phytoplankton which grow and reproduce rapidly, so a small mass can have a fast rate of primary production. In contrast, many significant terrestrial primary producers, such as mature forests , grow and reproduce slowly, so a much larger mass is needed to achieve the same rate of primary production.
The Food Chain & Fish
Define the role of marine microbes. Explain to students that, in a single drop of salt water, thousands of microbes tiny organisms , including bacteria and phytoplankton tiny floating plants , are interacting to form the base of the food web for the entire ocean. The oxygen and biomass they produce also sustains terrestrial life. Tell students that phytoplankton algae take in sunlight, nutrients, carbon dioxide, and water to produce oxygen and food for other organisms.
At the bottom of the food chain are microscopic plants and at the top are well-known predators like sharks and seabirds. Producers create their own food. These single-celled, microscopic plants float on top of the ocean, take in energy from the sun and use it to convert carbon dioxide and other nutrients into carbohydrates, which nourish other ocean life. Other types of phytoplankton are technically protists like diatoms and algae. They make up 95 percent of the primary producers on earth.