Invertebrates
Fiddler Crab
Uca spp.
Key facts
- Temperature22–30 °C
- pH7.5–8.5
- Adult size5 cm
- Difficulty★★★☆☆
Full profile
- Family
- Ocypodidae
- Origin
- Tropical and subtropical coasts (worldwide)
- Size
- shell 2–3 cm; male’s largest claw up to 4–5 cm
- Temperature
- 22 – 30°C
- pH
- 7.5 – 8.5
- GH / KH / TDS
- Salinity 1.005 – 1.015
- Difficulty
- ★★★☆☆
- Water type
- brackish
- Behavior
- Semi-aggressive (males fight using their larger claws)
- Compatible with fish
- Only with large, fast fish; may attack slow ones
- Diet
- detritivore (sediment, algae, microorganisms in the mud)
- Reproduction
- oviparous; planktonic larvae in seawater
Notes: The male has a highly developed pincer (violin-shaped) used in displays to attract females and in fights with other males. Semi-terrestrial: requires areas of exposed soil or sand above water (mangrove shoreline biotope). Very sensitive to copper. Not compatible with fish that could tear them apart.
