Marine Ecosystem

ocean · salt water · habitats · food webs

Oceans are massive. Marine ecosystems cover more than 70% of Earth's surface and contain 97% of all the water on our planet. That means the ocean is way bigger than all the land, mountains, and freshwater lakes combined.

Salt makes the difference. Seawater contains about 35 parts salt per thousand parts of water, which is what makes it taste salty and different from rivers and lakes. This salty water is home to creatures specially adapted to live in it.

Zones like neighborhoods. The ocean is divided into different zones depending on how deep the water is and what the shoreline looks like. Each zone, from the sunny shallow areas to the dark deep ocean, is home to different creatures.

Open ocean giants. The oceanic zone is the vast open part of the ocean where huge animals like whales, sharks, and tuna swim around. This is the biggest zone and has fewer hiding places than shallow waters.

Colorful coastal homes. Near the shore you can find amazing places like coral reefs, kelp forests, mangrove swamps, and seagrass meadows where thousands of creatures live together. These areas are some of the most lively and full of life on Earth.