The objectives of this study were: (1) to investigate the richness and composition of the Psittacidae in palm swamps; (2) to determine if the sizes of flocks vary seasonally; (3) to compare detectability rates according to species. Psittacid communities were observed from November 2006 to November 2007 in semimonthly visits to the area using fixed-point observation. A total of 1616 individuals from eight species were registered in 199 contacts. The palm swamps were highly similar (H > 0.62), and their diversity was above 1.56. The Yellow-chevroned Parakeet was considered resident in the three palm swamps (Fr > 60 %). The White-eyed Parakeet and Red-bellied Macaw were the most abundant species in the three areas. Most of the species (n = 5) were more abundant in one of the seasons. The most abundant species in the rainy season were the White-eyed Parakeet and Yellow-chevroned Parakeet (42.16 ± 30.77 individuals), whereas in the dry season the most prevalent was the Red-bellied Macaw (68.50 ± 39.35 individuals). The highest detectability rate was for the Yellow-chevroned Parakeet, which demonstrates the inter-species differences and the need to adapt the methods of research, unclear for this family. Los objetivos de este estudio fueron: (1) investigar la riqueza y la composición de pstácidos en pantanos, (2) determinar si el tamano de los grupos varía estacionalmente, (3) comparar las especies de acuerdo con sus tasas de detectabilidad. Ensambles de psitácidos han sido observados entre noviembre de 2006 y noviembre de 2007 con visitas quincenales en cada área a través de observación de punto fijo. Un total de 1616 individuos de ocho especies fueron registrados en 199 contactos. Los pantanos fueron muy similares (H > 0.62), y su diversidad de Psittacidae fue 1.56. Brotogeris chiriri ha sido considerada residente en los tres pantanos estudiados (Fr > 60 %). Aratinga leucophthalma y Orthopsittaca manilata fueron las especies más abundantes en las tres áreas. La mayoría de las especies (n = 5) fueron más ...