Direct answer
Yeti crabs are deep-sea crustaceans in the family Kiwaidae. Some grow chemosynthetic bacteria on hair-like setae and harvest those bacteria as food near vents or methane seeps.
Yeti crab names a small deep-sea family
Yeti crabs belong to Kiwaidae, a family first described in 2005. Their pale bodies and hair-covered appendages inspired the nickname.
Different Kiwa species live at hydrothermal vents or methane seeps and do not all use exactly the same behavior.
The hairs carry bacterial communities
Hair-like setae on the claws, chest, or legs provide surface for bacteria. At vents and seeps, those microbes can use reduced chemicals such as sulfide or methane-related compounds as energy sources.
The crab gains access to food produced without sunlight.
Kiwa puravida appears to farm its food
A 2011 study described Kiwa puravida waving bacteria-covered claws through seep fluid. Lipid and isotope evidence indicated the epibiotic bacteria were its main food source.
Specialized mouth appendages scraped the bacteria from the setae, supporting the farming interpretation.
Farming is a testable behavior, not a metaphor
Researchers linked arm waving, microbial growth surfaces, chemical-rich fluid, and feeding anatomy. The word farming summarizes that evidence but should not imply planning identical to human agriculture.
It describes behavior that increases microbial productivity and then harvests the result.
At a glance
| Feature | What the evidence shows | Example or boundary |
|---|---|---|
| Kiwa puravida | Methane seep | Waves claw bacteria through fluid |
| Hair-like setae | Host chemosynthetic bacteria | Harvested by the crab as food |
| Vents and seeps | Chemical energy, not sunlight | Habitat for the described species |
| Energy source | Chemosynthesis | No sunlight required |
Frequently asked questions
Are yeti crabs true crabs?
They are decapod crustaceans in their own deep-sea family, Kiwaidae.
Why are they hairy?
Setae provide surface for microbial communities and may have sensory roles.
Do they eat the bacteria?
For Kiwa puravida, isotope, lipid, behavior, and anatomy support bacteria as a major food source.
Are all yeti crabs the same?
No. Species differ in habitat, body form, and distribution of bacteria-bearing setae.
Evidence
Sources reviewed
- Dancing for Food in the Deep Sea: Bacterial Farming by a New Species of Yeti CrabPLOS ONE · checked 2026-07-30
- What is a hydrothermal vent?NOAA National Ocean Service · checked 2026-07-30
- The Deep SeaSmithsonian Ocean · checked 2026-07-30