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 accelerated when Dr. Mary Sears, impressed by her research quality, suggested Ángeles Alvariño to Dr. Roger Revelle, director of the Scripps Institution of Oceanography at 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 zooplankton off the coast of California and in the Atlantic, Pacific, and Indian Oceans. During this time, she identified twelve new Chaetognatha species, nine siphonophores, and one medusa.