A whirlwind spiral up an aquatic food chain goes like this: phytoplankton feed the zooplankton that feed the small fish and crustaceans that feed the larger fish that feed the even bigger fish that feed us.
Marine life education resources
Living organisms fill our ocean, estuaries, and coastal areas. These organisms take many forms from the tiniest single-cell plankton, to the largest mammal on Earth, the blue whale, and the largest colonial organism, the coral reef. Expanding our knowledge of the life cycle, habits, habitats, and inter-relationships of marine life is important to our understanding of the planet. Human interactions, influences, and reliance on these species as well as changing environmental conditions will determine the future health of these marine inhabitants. Toxic spills, oxygen depleted dead zones, marine debris, increasing ocean temperatures, overfishing, and shoreline development are daily threats to the existence of marine life. Part of NOAA's mission is to help protect these organisms and their habitats to ensure a sustainable balance of life.
Marine mammals are classified into four different groups: cetaceans (whales, dolphins, and porpoises), pinnipeds (seals, sea lions, and walruses), sirenians (manatees and dugongs), and marine fissipeds (polar bears and sea otters).
Sea turtles are air-breathing reptiles with streamlined bodies and large flippers. They are well adapted to life in the ocean and inhabit tropical and subtropical ocean waters around the world. Of the seven species of sea turtles, six are found in U.S. waters. These include the green, hawksbill, Kemp's ridley, leatherback, loggerhead, and olive ridley.
Imagine that you live in the sea and sometimes the water is salty and sometimes it is almost entirely freshwater. The water levels also rise and fall and even the chemistry of the water changes. How would you adapt to all these changes? These are the challenges of living in an estuary and the organisms that are found here are constantly adapting to different conditions.
Coral polyps, the animals primarily responsible for reef building, can take many forms: large reef building colonies, graceful flowing fans, and even small, solitary organisms. More than 6,000 species of coral are known, some live in warm, shallow, tropical seas and others in the cold, dark depths of the ocean.