Louisiana Waterthrush, Parkesia motacilla

Louisiana Waterthrush, Parkesia motacilla. Photograph taken within a residential community in Alamos, Sonora, February 2019. Photograph and identification courtesy of David F Smith, Alamos, Sonora.

The Louisiana Waterthrush, Parkesia motacilla, is a mid-sized members of the Parulidae Family of New World Warblers, which has one hundred eleven individual species that have been placed into eighteen genera, and one and one of thirty-four global members of the Setophaga Genus. They are known in Mexico as chipe arroyero.

The Louisiana Waterthrush is a large wood warbler. The sexes are similar in appearance, but the males have slightly larger bills and longer tails and wings. The adults have an olive-brown back, wings, tail, and crown with a white belly and undertail coverts, a brown streaked breast, and a broad white supercilium. They have small indistinct white spots at the tips of their outer tail feathers. Their bills are gray to black, their iris is brown, and their legs and feet are pink.

The Louisiana Waterthrush are normally found in close proximity to a moderate to high gradient streams and wide rivers at mid- and upper elevations in hilly and mountainous forests. They are known for their loud, ringing, resonant song. They are noted for constantly wagging its tail in a teetering motion as it walks along the ground. Their primarily food is aquatic invertebrates. They have life spans of up to twelve years. They are a complete migrant that withdraws entirely from breeding range annually by early fall and returning in the early spring. Migration occurs at night. The Louisiana Waterthrush has been poorly studied and very limited information about their behavioral patterns and biology has been documented.

The Louisiana Waterthrush is found during the winter months from Sonora, Nuevo León and Tamaulipas south to South America.

The Louisiana Waterthrush are similar to the Northern Waterthrush, Parkesia noveboracensis (larger bill, brighter pink legs, and a broader whiter eye line).

The Louisiana Waterthrush breeds in the United States and is a total migrant wintering in Central and South America. The Louisiana Waterthrush has been poorly studied and very limited information about their behavioral patterns and biology has been documented.

From a conservation perspective the Louisiana Waterthrush is currently considered to be of Least Concern with stable, widely distributed populations. Their long-term viability is threatened by deforestation and related loss of riparian forest canopy and stream pollution of both their breeding and wintering habitats. They are believed to a be good indicator of a stream’s ecosystem integrity.