Kadalundi Vallikunnu wetland located in Kerala holds sizeable number of birds. The species richness and diversity of birds in this wetland is documented by following line transect method during two years covering all the seasons. The three habitats documented include mudflat, mangrove and shallow water. Post monsoon season favors bird species richness than pre monsoon and monsoon seasons. Found some unique and rare species in this study. The rarefaction and Eigen value in the Principal Component Analysis revealed that mudflat has more species diversity than others. The three habitats are separated by distance of only 500 meter, the chance of habitat overlap is observed which altered the habitat preference behavior of shorebirds. This study highlighted the habitat preference of wetland birds and also the influence of some factors in their habitat selection. We observed the proliferation of mangroves into the mudflat habitat that induces habitat overlap.