Which ocean habitat is formed by dense underwater forests of kelp?

A kelp forest is an ocean habitat formed by dense underwater forests of large brown algae. Kelp grows mainly in cool, nutrient-rich coastal waters and can create several vertical layers from the seafloor to the surface.

Kelp attaches to rocky bottoms with holdfasts rather than true roots. Gas-filled structures called pneumatocysts help many species keep their blades near the light. Kelp forests provide food, shelter, and nursery habitat for fish, sea otters, seals, and numerous invertebrates.

Sea urchins can heavily graze kelp, while sea otters may indirectly protect kelp by eating urchins. Storms, marine heatwaves, pollution, and changes in predator populations can reshape these ecosystems. Kelp is an alga, so a kelp forest is not a true botanical forest despite its tree-like structure.