Rufous-Throated Dipper

Nests and Nest Site Characteristics of Rufous-Throated Dipper (Cinclus schulzi) in Mountain Rivers of Northwestern Argentina

Patricia N. Sardina Aragón, Natalia Politi and Rubén M. Barquez

The Rufous-throated Dipper or Argentine dipper (Cinclus schulzi) is an aquatic songbird found in South America, and is part of the dipper family. It is the subject of an article in the current issue of Waterbirds. The Rufous-throated Dipper lives along rapid rocky streams in the Andes in Bolivia and Argentina at 800 m to 2500 m in elevation. The bird breeds in the alder zone at 1500 m to 2500 m in elevation. BirdLife International have classified this species as "Vulnerable". Threats included reservoir construction, hydroelectric dams, and irrigation schemes. The current population is estimated at 3,000 to 4,000 individuals.

     The Rufous-throated Dipper (Cinclus schulzi) is an endemic and threatened bird that inhabits the mountain rivers of southern Yungas of Argentina and Bolivia. This is the rarest and least known species of the genus, in part because of its restricted distribution. The aim of this study was to describe the nests and nest sites of the Rufous-throated Dipper in mountain rivers of northwestern Argentina. Five rivers were surveyed in transects of 3 to 6 km long from 2010 to 2013. The shape, size, substrate and building material of nests and nest and non-nest characteristics were assessed and compared in plots of 2 by 2 m. Plots with nests were compared to non-nesting plots for a number of habitat characteristics. Most nests found (78.57%; n = 28) had a globular shape, were attached to rocky substrates and were built using moss. The height of nests above the water level (P = 0.02), slope (P = 0.03) and watercourse width (P < 0.01) varied among rivers. Plots at nest sites had significantly higher values of some habitat characteristics than non-nesting plots, including emergent rocks (P < 0.01), slope (P < 0.02), greater number of rapids (P < 0.01), number of pools (P < 0.01), water velocity (P < 0.05), and river depth (P < 0.01), but had narrower watercourse width (P < 0.01). Previously, the understanding of the breeding ecology of the Rufous-throated Dipper was based only on anecdotal evidence.