Her career ramped up when Dr. Mary Sears, impressed with the quality of her research, recommended Ángeles Alvariño to Dr. Roger Revelle, the director of the Scripps Institution of Oceanography, part of the University of California San Diego,  who offered her a position as a biologist. She worked at UCSD from 1958 to 1969 where she studied the zooplankton off the coast of California as well as the Atlantic, Pacific and Indian Oceans. During this period she discovered 12 new Chaetognatha species, nine siphonophore and one medusa.
Her career progressed when Dr. Mary Sears recommended Ángeles Alvariño to Dr. Roger Revelle at the Scripps Institution of Oceanography, part of the University of California San Diego, who offered her a biologist position. She worked at UCSD from 1958 to 1969 where she researched zooplankton along the California coast and in the Atlantic, Pacific, and Indian Oceans. During this period, she discovered twelve new Chaetognatha species, nine siphonophores, and one medusa.