Although the shadows on their faces make it difficult to see their red foreheads and light-colored upper beaks, I am fairly certain these are Red-lored Parrots (Amazona autumnalis). There is a chance, however, that they are Mealy Parrots (Amazona farinosa). Both species have wide, white orbital rings and stout, green bodies that make this parrot pair look like strange, inquisitive aliens climbing up a skinny branch.

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