Mammals allude to those among us whose animal nature is relatively pronounced. Fowl, because they can fly, allude to those of us who are less “earth-bound,” i.e., who live a more intellectual life and can therefore “fly” above a purely animal existence. Nonetheless, just as fowl need to periodically rest from flight, human intellect is limited by nature. Therefore, fowl, like mammals, are used as sacrifices, since both our animal natures and our intellects need to be spiritually refined and uplifted.
In contrast, fish, which must remain constantly in water, allude to those of us who have so refined themselves that they remain always connected to G‑d, “swimming” constantly in Divine consciousness. Since the Divine side of our personality does not need the elevation that our animal side does, fish are not used for sacrifices.1

Good 🌻 Morning!
Great Wisdom! GD is amazing! There is an omniverous South American fish that can leap 1.5 feet out of the Amazon waters to eat FRUIT and seeds from low hanging bushes. They are known as the Piraputanga fish. Remarkably, they often work together as a team. Teamwork is a sign of "good fruit!" :D These fish is an example of what it is like swimming, staying CONNECTED to GD, and constantly LEAPING into Divine Consciousness - Torah. TU!
Baruch HaShem,
🕊💜
"O Taste and See that the Lrd Is Good!" and His Fish. ;))