The primary predator of the sea otter is the orca.

The orca, or killer whale, is the primary predator of sea otters, particularly in coastal waters where both species coexist. As apex predators, orcas have a diverse diet that can include marine mammals like seals, dolphins, and, occasionally, sea otters. Orcas are known for their intelligence and sophisticated hunting strategies, which they use to catch sea otters, especially in regions where otter populations are vulnerable. While sea otters have few natural predators due to their size and agility, the presence of orcas can significantly impact sea otter populations. This dynamic highlights the interconnectedness of marine ecosystems, where each species plays a vital role in maintaining ecological balance.