Population study of Parathelphusa reticulata (Crustacea : Brachyura : Gecarcinucidae)

• Main Author: Tay, Vicki Weili
• Other Authors: Cai Yixiong
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Science
• Online Access: http://hdl.handle.net/10356/69192
• Institution: Nanyang Technological University

The Nee Soon Swamp Forest is the most important and last freshwater swamp habitat in Singapore housing freshwater flora and fauna. A particular freshwater crab species, Parathelphusa reticulata, is endemic to it and in low abundance. Extensive surveys on this crab were conducted over 10 weeks investigating its distribution, habitat characterisation, spatial and temporal variation in abundance. Trap samplings were carried out at 54 sampling sites, which represented the lower, middle and upper reaches of the stream system. Hydrological parameters were measured and habitat characterisations of the sites were conducted. P. reticulata tend to be in places with shallow waters, accumulations of leaf litter, in-stream macrophytes and high canopy cover. They are distributed at lower and middle reaches of NSSF and are relatively localised based on the Extent of Occupancy. Skewed sex ratio (1 female: 2.17 males) may be associated with growth rates, food restriction etc. Two cycles of hand samplings in the night were conducted at two sampling locations to study temporal variation. Sympatric aquatic species were documented and their possible impacts on P. reticulata were discussed. Data provide better understanding of the current distribution of P. reticulata and aid future conservation efforts in Nee Soon Swamp Forest.