# saltwater fish **URL:** \ **Category:** Factual Questions\ **Created:** [October 29, 2004, 5:34pm UTC](https://boards.straightdope.com/t/saltwater-fish/271887 "2004-10-29T17:34:58Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![merovingian](https://avatars.discourse-cdn.com/v4/letter/m/35a633/32.png) [@merovingian](https://boards.straightdope.com/u/merovingian)\ **Post date:** [October 29, 2004, 5:34pm UTC](https://boards.straightdope.com/t/saltwater-fish/271887/1 "2004-10-29T17:34:58Z")
Growing up in southern Florida. I’d always hear stories about people catching saltwater species in supposed freshwater lakes, canals, ect… I’m wondering what is the farthest that a saltwater species has been found to survive in fresh water. I think Salmon is a species that can live in both fresh and salt water, but I’m not sure. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 29, 2004, 9:28pm UTC](https://boards.straightdope.com/t/saltwater-fish/271887/2 "2004-10-29T21:28:57Z")
Eels also migrate between their marine breeding grounds and freshwater streams and even ponds (they can squirma across wet ground for quite some distance if conditions are right). Bull sharks can be found far upstream in large rivers. ---
**Author:** ![Selkie](https://avatars.discourse-cdn.com/v4/letter/s/bbce88/32.png) [@Selkie](https://boards.straightdope.com/u/Selkie)\ **Post date:** [October 29, 2004, 9:33pm UTC](https://boards.straightdope.com/t/saltwater-fish/271887/3 "2004-10-29T21:33:03Z")
Monodactylus argenteus (and I believe other members of the genus) lives in both saltwater and freshwater, and everything in-between. ---
**Author:** ![Rikster](https://avatars.discourse-cdn.com/v4/letter/r/e9a140/32.png) [@Rikster](https://boards.straightdope.com/u/Rikster)\ **Post date:** [October 31, 2004, 5:38am UTC](https://boards.straightdope.com/t/saltwater-fish/271887/4 "2004-10-31T05:38:38Z")
Bull Shark [http://shark-gallery.netfirms.com/med/bull.htm](http://shark-gallery.netfirms.com/med/bull.htm) It is found close to to shore and can live for a while in fresh water, frequenting estuaries, river and lakes. They have been found up to 1,750 miles up the Mississippi River in the USA and 2,500 miles up the Amazon River in Peru. ---
**Author:** ![Dan\_Turk](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dan\_Turk](https://boards.straightdope.com/u/Dan_Turk)\ **Post date:** [October 31, 2004, 7:28am UTC](https://boards.straightdope.com/t/saltwater-fish/271887/5 "2004-10-31T07:28:40Z")
you can acclimate your guppies(and often swordtails, mollies, platies…closely related) to be pure saltwater fish, too… it’s not too hard, and makes for some puzzled looks from friends “there’s a…um…guppy…next to your…anemone?” ---
**Author:** ![Spoke](https://avatars.discourse-cdn.com/v4/letter/s/a88e57/32.png) [@Spoke](https://boards.straightdope.com/u/Spoke)\ **Post date:** [October 31, 2004, 7:10pm UTC](https://boards.straightdope.com/t/saltwater-fish/271887/6 "2004-10-31T19:10:53Z")
> [@Rikster](#): > > Bull Shark > > [http://shark-gallery.netfirms.com/med/bull.htm](http://shark-gallery.netfirms.com/med/bull.htm) > > It is found close to to shore and can live for a while in fresh water, frequenting estuaries, river and lakes. They have been found up to 1,750 miles up the Mississippi River in the USA and 2,500 miles up the Amazon River in Peru. And in fact the freshwater sharks in Lake Nicaragua, thought until recently to be a separate species, are just plain old bull sharks that jumped rapids to get into the lake. [Cite.](http://animal.discovery.com/fansites/jeffcorwin/carnival/waterbeast/bullshark.html) Saltwater seems to be optional for these beasts.