SPECIES

Chilean Mockingbird Mimus thenca Scientific name definitions

Natacha González, Vicente Pantoja, Maria Jesus S. Mallea, Matías Garrido, Antoine Touret, Angélica Almónacid, Heraldo V. Norambuena, and Fernando Medrano
Version: 2.0 — Published March 3, 2023

Distribution

Introduction

The Chilean Mockingbird is the most common mockingbird in Chile. It is extensively distributed, covering all of central Chile continuously, with populations in the north (near the edge of the Atacama Desert) and in southern Chile (in the edges of the Valdivian rainforest), in Argentina, it is rare, locally common in Neuquén and Chubut.

Chile

Resident in Chile, distributed from Copiapó and Caldera (Atacama region) continuously south to Chaitén (Los Lagos region). It is the only mockingbird on Chiloé island (25). It is present on almost all islands close to the continent except Isla Mocha despite suitable habitat for their existence there (26, 27).

It has been recorded from 0 to 2,100 m above sea level (18, 28), with some giving the upper elevational limit as 2,200 m (4, 29), 2,400 m (30), or 2,500 m (31), with records up to 3,500 m (6, 32).

Argentina

Resident in Argentina (33), distributed only near the southern Andes, specifically from Minas and Chol Malal (Neuquén) to Futaleufú (Chubut), from 1,000 to 1,400 m (34). Almost entirely allopatric to the Patagonian Mockingbird (Mimus patagonicus), despite some populations being sympatric in a few locations (33; eBird).

Historical Changes to the Distribution

Historically, Hellmayr (18) described Chilean Mockingbird as ranging from Atacama to Cautín. After that, a continuous expansion was documented, with mockingbirds reaching Huasco (Atacama) to the north and Toltén river to the south in 1938. This southern expansion was derived from deforestation (35; 36). It was later reported in Manflas (Atacama) to the north (37). Years after, it was described between Copiapó valley to Valdivia province (38), and after that, various reports have been increasing its range to the south, reaching the north of Chiloé island (39, 40, 25), and even, an outlier record in Puerto Cárdenas (Aysén) in 1985 (41).

Currently, its range is more austral, as some authors mention its expansion to the south (6). Deforestation has helped the expansion of this species in a similar way to Northern Mockingbird (Mimus polyglottos) expanding northwards in the northern hemisphere (42, 6). However, several extensions of native vegetation were deforested, increasing the fragmentation of populations of Chilean Mockingbird (6).

The population in Argentina was discovered and described in December 2006. However, it was an already established breeding population with several individuals, so it is unknown when the population was founded (43). After that, several records were registered in eBird between Neuquén and Chubut.

A study showed that Chilean Mockingbird was the third most common bird in urban parks in Las Condes, Santiago during autumn 1992 (44). Nowadays, those numbers are different, and the Chilean Mockingbird is less common (Authors, personal observation). In Osorno, a study in 2008 compared bird diversity between two urban parks, where Chilean Mockingbird was absent in one of them (IV Centenario) (45). Nowadays, there is only one record of the species there (Silva, ebird S98520730), despite it being common near (ca. 1 km) that park.

Distribution of the Chilean Mockingbird - Range Map
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  • Year-round
  • Migration
  • Breeding
  • Non-Breeding
Distribution of the Chilean Mockingbird

Recommended Citation

González, N., V. Pantoja, M. J. S. Mallea, M. Garrido, A. Touret, A. Almónacid, H. V. Norambuena, and F. Medrano (2023). Chilean Mockingbird (Mimus thenca), version 2.0. In Birds of the World (N. D. Sly, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.chimoc1.02