I'm creating a fairly whimsical kid's fantasy world, so I don't need 100% accuracy- however, one of the major themes is respect for the environment (and spec evolution is a big interest of mine) so I like to make sure the creatures seem like they could potentially exist & have a natural history in an interconnected ecosystem, even if they're much sillier than actual hard sci-fi spec evo would be. Think, like, more grounded than moomins or pokemon but less grounded than any sci fi or fantasy media for adults.
In this world, there was a sudden, catastrophic, worldwide flood that wiped out most fully terrestrial and freshwater life. Many birds survived the initial flood because they could fly, but a lot of their old niches weren't viable anymore so the ones that wanted to survive longer had to adapt. Parrots, in the absence of fruits, nuts and seeds that their beaks evolved for, started foraging at newly-formed coastlines for small shellfish and invertebrates, eventually growing larger and becoming semi-aquatic flightless predators, somewhat like penguins.
My question is: parrot feet are heavily specialized for grasping branches. Many birds have three toes pointing forwards and one backwards. Parrots instead have two forward toes and two backward toes.
I know evolution finds it 'easier' to adapt already existing structures into new ones, rather than like, go back to a non-specialized foot and then re-adapt into a differently specialized foot. How might a a parrot's foot as-is change to suit an aquatic/semi-aquatic lifestyle, and how might that effect its underwater locomotion?