Imagine the sights and sounds of a forest.
Sunbeams slice through the darkness. The chirps and rustles of life surround you.
Now, imagine that that forest is underwater. What would it feel like to swim through an underwater forest?
Welcome to the kelp forest.
Here, you won’t find trees; instead, 150-foot seaweeds tower above you. Fish swim around you; sea lions frolic in the distance.
Your national marine sanctuaries are home to magnificent kelp forests that host an endless variety of fish, invertebrates, and plants. Like trees in a forest, kelp can grow in dense stands. These kelp groves provide hiding places to young fish and other animals that are hiding from predators; they help absorb wave activity and reduce erosion on nearby shores.
Kelp can grow nearly two feet a day. It has no roots – instead, claw-like holdfasts anchor it to the seafloor.
Kelp forests rely on a delicate balance to maintain their role as an ecosystem. Sea urchins, one resident of the kelp forest, is a big fan of kelp holdfasts. They chow down on these holdfasts, causing the kelp to lose its grip and float away. What’s left is known as an urchin barren.
Of course, the urchins aren’t particularly trying to destroy this ecosystem, but if the sea urchin population gets out of hand, it can spell real trouble for kelp forests. With too many sea urchins, you won’t just have a few urchin barrens here and there; instead the entire ecosystem is threatened.
That’s where sea otters come in.
Sea urchins are one of the otter’s favorite foods, so a healthy population of otters can help keep urchin populations in check.
With balanced populations of sea urchins, sea otters, and other creatures, kelp forests can thrive and serve as a refuge for fish, invertebrates, and other animals. That’s why we at NOAA do regular surveys to track kelp forest conditions, understand natural cycles and human impacts, and protect these majestic towers of life.