Diversity and habitat preference of brachyuran crabs in Gulf of Kutch ...

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Arthropods, 2012, 1(1):13-23
make 80% faunal biomass (Golly et al., 1962) and their density can reach up to 80-90 individuals per m 2
(Macintosh, 1984).
Gulf of Kutch, an indent to mainland of Gujarat is fourth major coral reefs areas of India. This area is
geographically isolated from other reef areas of India; still it shows great varieties of marine habitats like coral
reefs, mangroves, rocky intertidal zone and sea grass beds. The area is extensively explored by researchers as
far as Scleracitnian and molluscs groups are concerned. Total 45 different species of hard corals (Dixit et al.,
2010; Pillai and Patel, 1988) and 188 species of mollusc species were recorded in this area (Apte, 1998). Major
mangrove forest cover of the state lies in the area and the mangrove ecology is well studied with reference to
floral diversity but faunal component is least studied (Pandey and Pandey, 2010). Except few studies on
marine fauna of the then Mumbai state (Chhapgar, 1957) no particular studies on brachyuran crab fauna have
been done. So to generate the baseline picture of brachyuran crab diversity of Gulf of Kutch, the present study
was carried out at eight different sites of Gulf of Kutch. The main aim of the study is to generate the
information on brachyuran crab diversity and their habitat preference in selected habitats of Gulf of Kutch.
However, the area of Marine National Park and Sanctuary was not included in the present study.
2 Materials and Methods
2.1 Study sites
Gulf of Kutch is the western proximity of Gujarat state and as stated earlier, it harbors huge variety of marine
fauna. For the present study few locations of Gulf of Kutch (except Marine National Park and Sanctuary area)
were selected (Fig. 1). The study sites were not within the Marine national Park, however, considering the
legislative regulations collection, preservation or museum deposition of any specimen was not done.
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Fig. 1 Distribution of sampling sites in study area
The crab diversity was studied at eight different stations (Table 1). Selection of the stations was done on
the basis of two parameters; one is habitat diversity (e.g. mangroves mudflats, open mudflats and rocky shores)
and second is accessibility of the study site. The study area was classified in to three main habitat types; among
the mud flats; area near the low tide mark and with no vegetation cover was considered as open mudflat, the
mud flat which has mangrove canopy cover is considered as mangrove mudflats and the others included rocky
shores. Avicinia marina makes the major canopy cover of mangrove mudflats of the study area while the
canopy made by Rhizophora mucronata and Ceriops tugal were comparatively much sparse. Furthermore, the
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