What are two factors which account for the abundant marine life found at channel islands?

1) Upwelling: The Channel Islands are located in a region of strong upwelling, where cold, nutrient-rich water from the depths of the ocean rises to the surface. This upwelling brings with it essential nutrients that support the growth of phytoplankton, which in turn forms the base of the food chain for the diverse marine life found around the islands.

2) Unique Habitat: The Channel Islands are home to a variety of unique habitats, including kelp forests, seagrass beds, and rocky reefs. These habitats provide shelter and food for a variety of marine species, including fish, invertebrates, and marine mammals. The islands' proximity to the mainland also allows for the exchange of species between the two ecosystems, further contributing to the islands' rich biodiversity.