The chambered nautilus is a shelled relative of octopuses and squid, often called a living fossil. Its beautiful spiral shell has been prized by collectors for centuries.
Interesting facts
- Its shell is divided into chambers, and it controls its buoyancy by adjusting gas and liquid inside them.
- It has about 90 tentacles without suckers.
- Its simple eyes work like a pinhole camera, with no lens.
- It rises towards the surface at night and descends to deeper water by day.
- If it goes much deeper than about 800 metres, its shell can implode.
- It lives much longer than most cephalopods, which usually live only a year or two.
Behaviour
Nautiluses move by jet propulsion, pushing water out through a funnel. They find food mostly by smell, scavenging on the reef slopes.
Breeding and young
Nautiluses mature slowly and lay only a few large eggs a year, which take about a year to hatch.
Threats and conservation
Overfishing for the shell trade, which targets adults and can wipe out local populations.
Where to see it
- Osprey Reef, Coral Sea, Australia (night dives)
- Palau, on specialist dives
- The Philippines
- Public aquariums with nautilus exhibits
Status source: IUCN Red List. Profile last reviewed September 2026.
