Biology of the West African fiddler crab, Uca tangeri (Eydoux, 1835) (Decapoda: Ocypodidae) from a mangrove wetland in Lagos, Nigeria

Rasheed Olatunji Moruf, Teslim Asafe Ojetayo


The size distribution, allometric growth pattern, stomach analysis and sex ratio of the West African fiddler Crab, Uca tangeri in a mangrove wetland were investigated. The carapace length ranged from 1.11-3.7 cm and the weight 7.7-25.5 g. The crab exhibited negative allometric growth (b<3). No linear relationship was found between length and weight of U. tangeri as correlation coefficient (r) was 0.2464 for combined sexes. The condition factor ranged between 4.7 and 12.1, varying in relation to size and sex. The crabs fed mainly on detritus, diatoms, and algae with higher preference for plant materials. The males were significantly more numerous than females with the ratio 1:0.6. Uca tangeri is an ecologically important species in our marsh. Therefore, mangrove ecosystem should be effectively monitored for the conservation of this species.


Growth pattern, Feeding habits, Sex ratio, Mangrove.

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