By that standard the monarch butterfly is stupid too. That said they are smart enough to follow only a portion of their full migratory route which takes 4 generations to complete.
Squirrels remember where they bury their nuts. Octopuses can solve puzzles.
So what about fish? Salmon remember where they were spawned before they head out to the ocean, and come back to the exact same pool to spawn before dying.
Squirrel do not remember much though. They fill the ground with nuts. Then they dig the ground seemingly at random. Most of theis caches are forgotten. Which often leads to nuts trees sprouting all over the place during spring.
Squirrels remember where they bury their nuts. Octopuses can solve puzzles.
So what about fish? Salmon remember where they were spawned before they head out to the ocean, and come back to the exact same pool to spawn before dying.
https://blog.nationalgeographic.org/2013/02/13/mystery-solve...
So sure, they're not "SMART" but there is a lot of "intelligence" they have acquired over many generations of evolutionary cycles.