Photographed in the National Marine Sanctuary of American Samoa, the nautilus is a mollusk that uses jet propulsion to roam the ocean deep. Credit: NOAA/Michelle Johnston
Photographed in the National Marine Sanctuary of American Samoa, the nautilus is a mollusk that uses jet propulsion to roam the ocean deep. Credit: NOAA/Michelle Johnston
About the Species
Nautiluses are cephalopods—a kind of mollusk. Cephalopod means "headfoot", which reflects their relatively complex brain and the numerous tentacles. Nautiluses are related to squids and octopuses, but are easily differentiated by their distinctive, ornate, coiled shells.
Although their taxonomy is poorly resolved, the nautilus family, Nautilidae, is currently considered to include seven species in two genera, Nautilus and Allonautilus, all which share the common name, chambered nautilus.
The chambered nautilus, Nautilus pompilius, is a highly vulnerable species because of its life history characteristics, including low reproductive rates, slow growth, and late maturity. This species is thought to occur in small, isolated populations throughout its range. They are also limited by both depth and temperature tolerances. They have multiple predators, including sharks, bony fish, and octopuses.
Chambered nautiluses are primarily targeted for their shells, which are sold commercially and traded internationally for use in art, furniture, jewelry, and other items. In 2018, NOAA Fisheries listed the chambered nautilus as a threatened species under the Endangered Species Act.
Protected Status
ESA Threatened
CITES Appendix II
Appearance
Nautiluses are known for their beautiful, coiled shells. The shell can range in color, from white to orange, and even purple, with unique color patterns. Protruding from the shell are more than 90 suckerless tentacles.
Behavior and Diet
The soft-bodied nautilus lives inside a hard, chambered shell. It uses the chambers to pump air and water in and out of its shell, creating jet propulsion to thrust itself backwards and to make turns. They possess a siphon tube, known as a hyponome, which runs the length of the shell. The hyponome allows the nautilus to control its buoyancy by regulating air and water in the shell chambers. Nautiluses are hunters and pick up food scents in the water column with chemosensors on their tentacles. They consume animals such as fish, crabs, and lobsters with their sharp, beak-like mouth.
Where They Live
Chambered nautilus are mainly found in the western Pacific Ocean and coastal areas of the Indian Ocean.
Lifespan & Reproduction
Unlike other cephalopods, nautiluses are relatively long-lived, reaching ages of 15 to 20 years, or more. They grow slowly, maturing around 10 to 15 years of age, and produce a small number of eggs that require at least a year-long incubation period.
Threats
Harvest for International Trade
The primary threat to nautiluses is overfishing through commercial harvest to meet the demand for the international nautilus shell trade. Chambered nautilus shells, which have a distinctive coiled interior, are traded as souvenirs to tourists and shell collectors and also used in jewelry and home décor items (where either the whole shell is sold as a decorative object or parts are used to create shell-inlay designs). The trade in the species is largely driven by the international demand for their shells and shell products since fishing for nautiluses has been found to have no cultural or historical relevance. While all nautilus species are found in international trade, N. pompilius, being the most widely distributed, is the species most commonly traded. Given their slow growth, late maturity, low reproductive output, and low mobility, chambered nautiluses are particularly vulnerable to overfishing. Efforts to address overutilization of the species through regulatory measures appear inadequate, with evidence of targeted fishing of and trade in the species, particularly in Indonesia, Philippines, and China, despite prohibitions.
Scientific Classification
| Animalia |
Mollusca |
Cephalopoda |
Nautilida |
Nautilidae |
Nautilus |
pompilius |
Last updated by NOAA Fisheries on 03/16/2022
