In nearshore marine ecosystems, the sea otter plays a critical role in maintaining the ecological balance of coastal kelp forests. Kelp forests are underwater areas with a high density of kelp canopy, supporting a diverse array of marine life. Sea otters feed primarily on sea urchins, which are herbivorous invertebrates that graze heavily on kelp. Without sea otters to control the urchin population, these invertebrates quickly multiply and consume entire forests of kelp, creating barren seafloors known as 'urchin barrens.' While sea otters also consume crabs, clams, and other invertebrates, their predation on urchins is their most ecologically significant behavior. By keeping the urchin population in check, sea otters indirectly protect the habitat of hundreds of other species, including various fish, snails, and crabs that rely on the kelp for shelter and food. Ultimately, the presence of sea otters is essential to preserving the overall health and biodiversity of the entire nearshore marine community.
Which of the following statements best expresses the main idea of the passage?
- ASea otters consume a variety of invertebrates, including sea urchins, crabs, and clams.
- BAll marine predators are essential for protecting their ecosystems from ecological collapse.
- Sea otters play a crucial role in maintaining the health and biodiversity of nearshore marine ecosystems by controlling the population of sea urchins.Answer
- DKelp forests are the only underwater ecosystems that can support a diverse array of marine life.