Invertebrate
Invertebrate
Freshwater Shrimp
Macrobrachium species
Freshwater Shrimp of the genus Macrobrachium are common and ecologically important inhabitants of Trinidad's rivers and streams, several species supporting small-scale local fisheries and prized for their size and flavour.
Freshwater Shrimp of the genus Macrobrachium are common and ecologically important inhabitants of Trinidad's rivers and streams, several species supporting small-scale local fisheries and prized for their size and flavour.
Identification
Elongated, laterally compressed crustaceans ranging from a few centimetres to, in the largest local species, over 20 cm including greatly elongated, clawed front legs used for defence and prey capture. Colouration is typically translucent to greenish-brown, helping them blend with submerged vegetation and debris.
Behaviour
Forages mainly at night among submerged roots, leaf litter, and rocky stream substrate for algae, detritus, small invertebrates, and occasionally small fish. Most species have a life cycle that requires migration between freshwater rivers and brackish or estuarine water for larval development, meaning free passage along rivers to the coast is important for maintaining healthy populations.
Status in T&T
Common in rivers and streams across Trinidad, supporting small-scale artisanal fisheries in some areas. Not considered threatened as a group, though individual populations can be affected by river damming, pollution, and barriers that block the migration route between fresh and brackish water needed for reproduction.
Threats
- River damming and barriers blocking migration to brackish water
- Water pollution
