Estudo de haplótipos do DNA mitocondrial de colhereiros (Aves, Ordem Ciconiiformes, Platalea ajaja)

Abstract

Roseate spoonbill (Platalea ajaja) is a neotropical bird with wide geographic distribution in intercontinental and coastal wetland habitats. Populations are morphologically indistinguishable, with no apparent differentiation from the southern United States to northern Argentina. In this study we aim to determine the genetic diversity and to delineate the Brazilian population structure of this specie, using genetic data of a 483 base-pair fragment of the first domain of the mitochondrial DNA control region. Samples of 50 individuals were collected from five breeding colonies in two important Brazilian wetland areas, the Pantanal (four colonies, n = 39) and the Banhado do Taim (one colony, n = 11). The levels of variability estimated using nucleotide (π) and haplotipic (H) diversities were higher in the Pantanal (π = 0.004 and H = 0.753) than in Taim (π = 0,0004 and H = 0,182). No significant levels of genetic differentiation among Pantanal colonies (Fst and AMOVA values are not significant) and between Pantanal and Taim colonies (Fst and AMOVA values are not significant) were found. The unimodal pattern of the mismatch distribution and the neutrality tests results (Tajima`s D = -1,942, Fu = -23,271 and R2 = 0,055) pointed a recent expansion in the Pantanal population. The time since the expansion was estimated to be 30242 years before present and the Ne was estimated as 14556 females. Our results were discuss considering that the present Pantanal population was originated from a geographically limited founder population. The Ne estimates indicates that the Pantanal population represents around 10-30% of Roseate Spoonbill continental population.