Saving the chambered nautilus
The chambered, or pearly, nautilus (Nautilus pompilius) is a charismatic cephalopod species known for its exceptional spiraling, chambered shell. It belongs to a family that has barely changed since appearing in the fossil records around 500 million years ago, leading scientists to describe it as a “living fossil.” Its fractal shell designs are so beguiling that consumer demand for the shells is pushing the animals toward extinction.
Populations of the chambered nautilus are now at risk of going extinct from overfishing to satisfy the international shell-trade market. Evidence shows that unique nautilus populations have been unsustainably harvested in some areas of the Philippines, and that local extirpations have already occurred. Other fished nautilus populations are also believed to be declining.
Unique life-history characteristics such as slow growth rates, low fecundity, and long generation and gestation times also make the chambered nautilus vulnerable to even low levels of fishing intensity. In this sense the species is more similar to oceanic sharks than its cousins, squids and octopi. Chambered nautiluses have a very restricted capacity to rebound, since migration and population distribution is limited, resulting in isolated populations with poor or no connectivity. The loss of isolated populations thus represents a loss in genetic biodiversity and potential loss of unique subspecies.
The Center, with the support of members of the scientific community who are working on the chambered nautilus, in 2016 petitioned the National Marine Fisheries Service to protect the chambered nautilus under the Endangered Species Act. In response to our petition, in 2018 the agency protected the nautilus as threatened.
The greatest danger to this unique species' continued survival is overfishing. Other ongoing and growing threats include habitat degradation, climate change, and life-history characteristics that render the nautilus particularly vulnerable.