Dispersion And Sexual Maturity Of Mergus Octosetaceus Vieillot, 1817 In The Serra Da Canastra, Minas Gerais, Brazil

Dispersion and sexual maturity of Mergus octosetaceus Vieillot, 1817 in the Serra da Canastra, Minas Gerais, Brazil. The Brazilian Merganser (Mergus octosetaceus) is a Critically Endangered species that occurs at low densities in clear streams with rapids. The Serra da Canastra National Park region, in Minas Gerais, has the largest and most well known population of the species. We conducted research involving banding and marking with radio transmitters in the region of this National Park. In September 2010, a young male of M. octosetaceus, aged between 60 and 90 days, was captured and marked on the Sao Francisco river. After that, this individual was registered on some occasions in this same river, until April 28, 2011. Less than two months after, this male was recorded nesting in the Santo Antonio river. The straight line distance between the rivers of origin and destination is of 19,3 km, and each river is located on opposite sides of the Canastra plateau. Possible dispersal routes are discussed. This paper presents the first record of M. octosetaceus dispersal and first data on sexual maturity of this species.