Is there any sort of habitat within which both saltwater and freshwater species could survive?

Question

I'm not thinking of a normal habitat that might occur in nature, but rather a bio-engineered habitat. It seems to me that one actually could evolve a habitat with a mixture of microorganisms that are evolved to be responsive to certain very specific fish in certain very specific ways - ways which may enable a fish not normally accustomed to one type of water to handle it at least at a tolerable level.

There's not necessarily an ultimate "purpose" for such a scenario, I'm just curious if we currently have the knowledge that would be required to produce such a thing. It would make for some interesting "novelty aquatic displays", I'd think.

Answer 1

some species (like sea mammals and reptiles) could easily survive in fresh or salty water, preferrably salty, though. but fish rely on salinity to control their cell´s osmosis, and if a saltywater fish is placed on fresh water, it cells may explode (but dies earlier hehe), and if a freshwater fish is placed on salty water, it will dehydrate.

Answer 2

Yes it is possible. Such habitats do exist in nature, marshes, lagoons, estuaries etc.

Maintaining such a habitat would be difficult artificially because neither the fresh water or the marine species stay in such area for long. They just come to feed (marine hunts freshwater) and breed (both).

Answer 3

You do know that there are fish that can survive in both fresh and salt water right? (along with many crustaceans, and bacteria)


as for your question- It was kind of hard to understand- but what i think your trying to get at is almost like Darwin's theory of natural selection. (just google it if you don't know what it is- I'm too lazy to explain what it is and how it relates to this... maby ill edit it later... =P)

Answer 4

I went fishing at a trout farm once. The trout are fresh water fish but to keep them disease free, the owners pour bags of salt into the trouts water and It doesn't kill the fish.

Answer 5

There are salt tolerant organisms that might serve your purposes but electrolyte level is an internal parameter affecting nerve function. I doubt that any external influence would greatly alter the salt tolerance of any individual organism.

Answer 6

I THINK actually, that some wetlands found in nature can have freshwater and saltwater species existing in the same area.