Opalescent squid eggs (Doryteuthis opalescens) are contained within a capsule that may hold 180 to 300 individual eggs. Opalescent squids live near shore and mate in large gatherings near the end of their lifespans. The resulting fertilized eggs are deposited by females in protective capsules in shallow sandy bays or mudflats. These capsules are made up of many layers of protein. When females see other deposited egg capsules, it stimulates them to also lay their own so that large clusters can form into what are called egg beds. Some egg beds can literally cover acres of area on the ocean floor.