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Underwater Forests

4 minutes

(Describer) Under a round logo of a wave, title: Ocean Today.

(Describer) Sliding out from dark leaves, title: Underwater Forests.

(female narrator) Kelp forests exist along much of the West Coast of North America. Kelp are actually large brown algae that live in cool, relatively shallow waters close to the shore. They grow in dense groupings, much like a forest on land. These underwater towers of kelp provide food and shelter for thousands of fish, invertebrate, and marine mammal species. Kelp are very simple organisms that consist of a holdfast, a stipe, and blades. At the bottom is a root-like structure called a holdfast that anchors kelp to rocks and other materials on the ocean floor. Young kelp must compete for space to settle and grow, as the rocky bottom is carpeted with smaller algae and invertebrates like anemones and sponges. The stipe is similar to a plant stem. It is strong, yet flexible, allowing kelp to sway in the currents of the ocean. Many fish use this middle area of the kelp forest as hunting grounds. The blades contain a special gas which act like a float, keeping the kelp blades close to the water's surface where they absorb energy from the sun. This ability to float raises the kelp to the sea surface, forming a dense canopy. The canopy serves as a nursery or brood area for many organisms, due the warmer surface temperatures and slower water currents. Many organisms, from small fish to birds, and even whales, use the thick blades as a safe shelter for their young from predators or even rough storms. Kelp forests have a greater variety and higher diversity of plants and animals than almost any other ocean community. NOAA's scientists study kelp forests by visiting the same locations over and over, to assess the presence and abundance of a variety of organisms. Monitoring allows marine scientists to determine if the kelp forest is changing over time, and to identify the cause of those changes, whether natural or human. Healthy kelp forests maintain the existence of thousands of plants and animals, fish stocks, and many ocean and tourism-based businesses. All of these require a thriving ocean ecosystem. We all depend on the ocean for food, oxygen, and even life-saving pharmaceuticals. Do your part to keep our ocean and local waterways clean, litter-free, and healthy.

(Describer) Sunlight filters down to the stalks of kelp. Logos are shown for the Smithsonian and NOAA. Accessibility provided by the US Department of Education.

Accessibility provided by the U.S. Department of Education.

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Kelp forests can be seen along much of the West Coast of North America. NOAA scientists study kelp forests by visiting the same locations over and over to assess the presence and abundance of a variety of organisms. Monitoring allows marine scientists to determine if the kelp forest is changing over time and to identify the cause of those changes, whether natural or human. Healthy kelp forests maintain the existence of thousands of plants, animals, and fish stocks. All of these require a thriving ocean ecosystem.

Media Details

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