Hmm. Aren’t the Great Lakes in North America connected to each other and then to the St. Lawrence River via Lake Ontario, which eventually leads to the Atlantic Ocean? Maybe the map should include those large bodies of water too.

[–] DemBoSain@midwest.social 7 points 10 months ago (1 children)

Lampreys are the greatest explorers among saltwater fish. They've mapped most of deepest darkest Greatlakesica, but most don't make it back out to report their findings.

[–] mick@lemmy.world 2 points 10 months ago (1 children)

How do biologists determine that the lampreys migrated from the ocean versus being hatched/born in the Great Lakes?

[–] Everythingispenguins@lemmy.world 4 points 10 months ago

Accent. You can take the fish out of the ocean but you can't take the ocean out of the fish.

[–] teft@lemmy.world 7 points 10 months ago

There are fish that go from saltwater to freshwater or vice versa. They're called anadromous fish. Salmon are one species like that. So you'll have to include every river as well.

[–] Horsey@kbin.social 3 points 10 months ago* (last edited 10 months ago)

Niagra falls is a one-way trip into the Great Lakes, although it does look like there are other passages through that area for fish.