The Coronado Islands are a group of islands located 13 km (8 mi) off the northwest coast of the Mexican state of Baja California. Battered by the wind and waves, the rocky islands are mostly uninhabited except for a small military detachment and a lighthouse keeper. Despite their barren appearance, they serve as a refuge for seabirds and support a sizable number of plants, including 6 endemic taxa found only on the islands. The waters around the islands support a considerable amount of diverse marine life.

The Channel Islands are an eight-island archipelago located within the Southern California Bight in the Pacific Ocean, off the coast of California. They define the Santa Barbara Channel, which sits between the islands and the California mainland. The four Northern Channel Islands are part of the Transverse Ranges geologic province, and the four Southern Channel Islands are part of the Peninsular Ranges province. Five of the islands are within the Channel Islands National Park, and the waters surrounding these islands make up Channel Islands National Marine Sanctuary. The Nature Conservancy was instrumental in establishing the Channel Islands National Marine Sanctuary.