Calmars

Calmars is the plural form of calmar, a common name for squid in several languages. Squids are pelagic cephalopods found in oceans worldwide. They belong to the class Cephalopoda and the order Teuthida and are characterized by an elongated mantle, eight arms, two longer tentacles, and paired fins on the mantle.

Physiology and locomotion: The body is streamlined for fast swimming. Squids propel themselves by jetting water through a funnel (hyponome). They have complex eyes and high brain-to-body ratios. In most species the circulatory system includes two branchial hearts and one systemic heart, distributing oxygen throughout the body. They often display rapid color changes using chromatophores for camouflage, signaling, or communication.

Habitat and diet: Calmars inhabit open oceans from shallow continental shelves to deep pelagic zones; many species undertake vertical migrations between day and night. They are carnivorous, feeding on fish, crustaceans, and other cephalopods. Predators include larger fish, marine mammals, and seabirds. Reproduction involves males transferring spermatophores to females; females lay egg capsules or masses that attach to substrates and hatch later.

Life cycle and variation: Lifespans are typically short, often one year or less, with rapid growth and high juvenile survival in favorable conditions. Some species exhibit bioluminescence and complex mating behaviors. Conservation status varies by species; many are not threatened, but overfishing, bycatch, and climate change can affect populations.

Human interactions: Calmars are widely harvested for food in many regions. They are caught by various methods including purse seines, trawls, and jig fleets. They play a significant role in marine ecosystems as both predators and prey.