What are euryhaline and stenohaline organisms?

Euryhaline organisms can adapt to a wide range of salinities. Salinity is the level of salt in water.

Therefore, euryhaline organisms can live in freshwater, brackish water (light salt water), and salt water.

This means that euryhaline organisms can live in freshwater rivers, streams, creeks, and ponds. They can live in estuaries and tidal pools where rivers meet the sea. They can live in marine water – the oceans and seas.

Euryhaline organisms are fish and aquatic animals. Euryhaline organisms include the Molly (Poecilia sphenops), the Guppy (Poecilia reticulate), the Green Crab (Carcinus maenas), and the Atlantic Stingray (Dasyatis sabina). 

Salmon, herrings, puffer fish, sturgeons, tilapia, trout, barramundi, perch, and eels are also euryhaline organisms. 

Stenohaline organisms can only live in one type of water salinity. Stenohaline organisms that live in freshwater will die if they swim in sea water. Stenohaline organisms that live in saltwater will die if they swim in freshwater. 

Photographer: Martina Nicolls

Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM