Ucides Cordatus (Mangrove Crab)

The Ucides Cordatus (Mangrove Crab) is a large, burrow-digging mangrove crab found on sheltered mudflats and brackish backwaters. On the west coast, it occurs in great numbers on the broad mudflat just south of Portsmouth, and it is also recorded near the mouth of the Layou River among coconut groves and low, waterlogged ground in the Layou Valley. Burrows cluster at the base of mangrove stands typical of mangrove swamps, with entrances exposed at low tide.

Ecological and Cultural Significance

Ucides Cordatus lives in mangrove forests in intertidal zones, often near upper limits of high tide. Its burrows may reach depths of 70 cm or more, extend down to the water table, and are located under vegetation or in open ground. It forages on fallen mangrove leaves, algae, and small invertebrates, and in turn is prey for wading birds and nearshore fishes within Dominican wildlife. Adults are stout, gray-blue to slate with sturdy claws and a carapace that can reach about 7 cm across, well adapted to pushing through soft sediments and defending burrow entrances.

Sightings and Best Viewing Areas

Look for fresh spoil heaps and oval burrow mouths on mid to low tide. Quiet observation along the edge of the mudflat south of Portsmouth often reveals individuals emerging to feed before retreating as the water rises. Similar signs appear around the Layou estuary, where calm conditions allow easy viewing from firm ground. Nearby paths and viewpoints around Cabrits Marine Reserve provide orientation to the wider mangrove shoreline and its associated crabs.