In 1940, John Steinbeck and Ed Ricketts chartered a purse seiner, the Western Flyer, for a 6-week expedition to the Sea of Cortez. They captured and catalogued marine invertebrates (animals without backbones) at 21 different sites along their route. In 1941, the two friends published Sea of Cortez, a narrative account of their journey and a “phyletic catalogue”of all the species they found. The catalogue includes 484 species of marine invertebrates! This summer, the Western Flyer Foundation invites you to take an expedition to your local coastline to catalogue and identify as many marine invertebrates as you can using iNaturalist. A Bioblitz is an event that focuses on finding and identifying as many species as possible in a specific area over a short period of time. The intertidal zone is the area of a seashore which is covered at high tide and uncovered at low tide.