Through connecting bodies of water: >>16706179 like streams, creeks, rivers, storm drain ponds, or even flood waters.
Their eggs can also be transported on the bodies of water fowl: >>16705865
Some fish can also crawl to new water sources like snakeheads.
There are a million ways for fish to get into ponds, lakes, and rivers. If it's a reservoir, modern pond, lake, or whatever then man put them there. It's as simple as that. Most bodies of water don't have shit in them.
Nowadays, there's usually government programs that put them there.
Historically, all the pathways previously mentioned. Even "isolated" bodies of water aren't always that way year round. Floods can cause typically disconnected bodies of water to flow into each other for a period of time allowing fish to cross over.
Sometimes birds will scoop out fish from ponds and drop them in a different pond. Also fish can disperse by flooding events, among other dispersion methods.
All this means that you can find fish in even the most isolated lakes in America.
>>16706208
There are shrimp who live in the puddles formed after heavy rains on Stone Mountain, Georgia. Most of the time, the puddles don't exist as the water evaporates in the hot Georgia sun. Nevertheless, the shrimp are there when there's enough rain to create puddles in the rocky surface as their eggs are able to survive each cycle of evaporation and rain.
>>16705852 (OP)
There are very few truly isolated bodies of water, almost all of them are connected trough streams and rivers at least seasonally all the way to the oceans. Beyond that and things like fish hitching a ride using animals like birds or humans deliberately spreading them you have to consider geological timescale, all low points that would form lakes in places like Canada and Scandinavia were connected at one point or another during the last ice age or rather the ending of it by melt water streams and lakes or by channels that were later filled with debris which is very recent as far as fish are concerned.
Lots of eels and similar fish travel over land. In Australia Longfin Eels are so absurdly hardy and adaptable and travel such great distances land that they live in just about every single body of water the size of a pond and larger that isn't surrounded by kilometers of desert. They also sometimes get locked in these locations and can't go to the ocean to breed (they die like salmon when they do) so they grow from the normal eel size of a meter to a meter and a bit to nearly 3m long. Pick related is a gigantic one cut in two
Fish get around so easily that the US government spends billions (with a b) on things like underwater electric fences to keep them from moving into new territory.
>>16707017
thats a weird fish
but what i was thinking of was like a pond that had no fish in it and then a land animal evolved to be a fish in the pond or a fish that evolved from nothing inside the pond
>>16707020 >what i was thinking of was like a pond that had no fish in it and then a land animal evolved to be a fish in the pond or a fish that evolved from nothing inside the pond
Lolno. Nobody's suggesting that's what happened.
