I think we may be close to an even split on the bird-stocking aspect here on the forum.

I believe it happens, instinct wise, by a bird like a heron moving live fish.

I don't think the bird egg transport thing is real, but I suppose it has a snowballs chance.

Stocking by human (Ole Mudcat Joe) is the first go-to reason for seeing an odd fish in a body of water, but beyond that, I believe certain birds will move live fish.


Excerpt from Robert Crais' "The Monkey's Raincoat:"
"She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."