Translation of "Taint" in Portuguese

Back, from another quarter of the sky, / dark-ambushed, round the clamorous Harpies fly / with taloned claws, and taste and taint the prey.

Vindo de esconderijos invisíveis, / de outro ponto do céu surge o estrídulo bando; / cai novamente voejando sobre nós, / os pés em garra, as bocas repugnantes / sujando as iguarias.