Freshwater crab Nature (IUCN); of the species for which data are available, 32% are threatened with extinction. For instance, all but one of Sri Lanka's 50 freshwater crab species are endemic to that country, and more than half are critically endangered. Freshwater crab There are around 1,300 species of freshwater crabs, distributed throughout the tropics and subtropics, divided among eight families. They show direct development and maternal care of a small number of offspring, in contrast to marine crabs which release thousands of planktonic larvae. This limits the dispersal abilities of freshwater crabs, so they tend to be endemic to small areas.
Freshwater inflow Freshwater inflow Environmental flows can be broken down into instream flow, freshwater inflow, and outflow, as shown in the depiction below. Instream flow is the freshwater water flowing in rivers or streams. Freshwater inflow is the freshwater that flows into an estuary. Outflow is the flow from an estuary to the ocean. This article's focus is upon freshwater inflow. Freshwater inflow: Freshwater flows into an estuary and mixes with the marine water of the estuarine ecosystem. The mixing of freshwater inflow and the marine water of the estuarine ecosystem occurs spatially and temporally from climatic influences including tidal action, seasonal