In order to reproduce, male squid species create a single bundle of sperm, called the spermatophore, which they utilize to fertilize female squids through the central mantle cavity. Male squids have a specially developed appendage just to place the spermatophore within the cavity of the female squid, whereas females have special glands found within the body that manufactures nutrients and forms the shells of the fertilized eggs. Following this, the female squids plant these spermatophores in clusters that are commonly deposited to the seafloor itself or to algae or other features present in the surrounding environment. Squid eggs are also communal and multiple squids will contribute to the eggs, each of which holding up to 200 eggs inside. These eggs are commonly mass-produced in the squid family as squids themselves, as well as their eggs, are preyed on by a host of predators such as sharks, whales, dolphins, sea snakes, eels, among other sea creatures. Research by Francisco Rocha and peers demonstrates five flexible cephalopod reproductive strategies, including semelparity, iteroparity, group-synchronous ovulation, intermittent terminal spawning, and continuous spawning with asynchronous ovulation (Rocha et al., 2001).
Furthermore, upon the deposition of the egg capsules to the seafloor or it’s environment, the female squid will imbue them with a protein by the name Loligo microseminoprotein, which is said to drive male squids crazy. This is said to be the first substance triggering aggression in marine organisms, as any other creature, even one of the same family, will likely be bruted by the male who has come in contact with the eggs. Males will grapple, flare their appendages, charge their opponent, engage in fin beating, as well as other aggressive behaviors brought on by the eggs and their allure.
This process, though universal to almost all species of squid, is not the same for the Gonatus onyx, one specific species that commonly resides in shallow waters. Though this is the environment in which they frequent, these squid will descend to drastic depths to lay vast quantities of eggs, said to be in the ranges of two to three-thousand. These squid additionally do not anchor or attach the eggs to the seafloor, but instead carry them around, frequently suspending the egg mass from hooks attached to the squid’s arms. Water is also pumped into the tubular egg clusters in order to maintain the survivability of the eggs and provide them with necessary water and oxygen. Often however, this leaves the female squids susceptible to predatory organisms in the surrounding environment as the large sack limits the speed and mobility of the invertebrate.