chris
So I have a feeling you may have confused the flamingo with yellow billed Oxpeckers, which eat the parasites on a hippos back. The Oxpecker gets food, a home, and protection from the hippo, and the hippo gets to deal with less parasites, so they relationship benefits them both quite a bit.
If you really did mean flamingos, though, I really don't think they pay each other any mind.
?
There are birds who help hippos with grooming and dental hygiene by picking hippos teeth and cleaning them. Maybe flamingoes are one of those birds. I always thought smaller bird breeds are the only ones who help hippos with that but I could be mistaken.
Elaine M
They're not competing for the same food or living space. Neither is a predator of the other.
Anonymous
Hippos are not hunters. Flamingoes are no threat to hippos.
daniel g
They pose no threat to each other, like deer and rabbits.