Flora index
Fauna index
guide to the mangroves of singapore
Peter K L Ng and N Sivasothi (editors)
Fiddler crabs
Uca spp.
Family Ocypodidae

There are some eight species of fiddlers in Singapore, most of which occur in mangroves or along the shore.

Males are characterised by a greatly enlarged claw while the other is small with spoon-tipped fingers. The large claw is used to court females as well as fend off male rivals. The 'courtship wave' of fiddlers is diagnostic for each species. The smaller claw is used for feeding.
close-up of battling fiddlers
Two crabs grappling pincers

wide shot of fiddlers among pneumatophores
Colony of fiddler crabs
waving their larger claws

Fiddlers prefer to live out of water on damp ground; even when they are sealed in their burrows during high tide, they maintain a bubble of air underground! They have tufts of hair at the base of their legs which they use to absorb water into their gill chamber through capillary action.

close-up showing large orange claw Orange fiddler
Uca vocans
3-4 cm
The Orange fiddler is very common on sandy-muddy substrates, often at the edge of mangroves.

close-up showing large rosy claw Rosy fiddler
Uca rosea
2 cm
  close-up of colourful crab on mud
The Rosy fiddler is found mainly in back mangroves, on firmer mud.

This beautiful species was described in 1940 from Singapore. Today, it is highly endangered locally because most of Singapore's back mangroves have been lost.
crab on mud displaying
Uca annulipes displaying
Porcelain fiddler
Uca annulipes
2-2.5 cm
The Porcelain fidder prefers slightly sandier substrates and can be found on sandbanks.

close-up showing colourful face Purple fiddler
Uca paradussumieri
up to 5 cm
The most striking species is the Purple fiddler. close-up of crab
It is an obligate mangrove crab, and often occurs in soft mud. Juveniles build chimney-like burrows.

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What is mangrove?

The Ecosystem


Indirect uses
Potential uses

About Mangroves
in Singapore

Mangroves to visit
From "A Guide to Mangroves of Singapore", Peter K. L. Ng and N. Sivasothi (editors)
Volume 1: The Ecosystem and Plant Diversity and Volume 2: Animal Diversity
Authors: Kelvin K. P. Lim, Dennis H. Murphy, T. Morgany, N. Sivasothi, Peter K. L. Ng,
B. C. Soong, Hugh T. W. Tan, K. S. Tan & T. K. Tan
BP Guide to Nature Series published by the Singapore Science Centre, sponsored by British Petroleum
2001 Raffles Museum of Biodiversity Research, The National University of Singapore & The Singapore Science Centre