Abstract:
Viddler crab is a type of crab that lives in holes or soaks in the substrate of mangrove
ecosystem. This research was conducted from January to April 2020 in the Sungai Rawa
Mangrove Ecotourism Area. The purpose of this study was to determine and obtain
correlation values between condition of mangrove ecosystem and the abundance of viddler
crabs. Survey method used in this research was purposive sampling technique. This study
found 7 types of mangroves namely Avicennia marina, Avicennia alba, Avicennia officinalis,
Sonneratia alba, Sonneratia ovata, Rhizophora mucronata, Rhizophora apiculata. The
mangrove condition at the observed station was in the rare (damaged) category. Mangrove
density in transect 1, 2 and 3 were 775 trees/ha, 375 trees /ha, and 200 trees /ha, respectively.
The highest abundance of viddler crab was 4500 ind /ha found in station 1, while the lowest
abundance was in station 2 where fiddler crab species was not found. The correlation between
the existence of viddler crab and mangrove density showed a strong positive relationship. It
means that the higher value of mangrove density leads to the high abundance of viddler crab
