Justification of Red List Category
This species is restricted to a small range on a single island. The population is moderately small, but stable and currently not under imminent threat. The species is therefore listed as Near Threatened.
The species is widely distributed throughout its range. Until recently, the population was believed to be small; however, following a thorough survey the population size is now estimated at 10,000-19,000 breeding territories (Dvorak et al. 2019), which equates to 20,000-38,000 mature individuals.
Surveys in the 1980s and in 2010-2017 recorded the species at a density of c. 0.6 individuals/ha (Curry 1989, R. Curry in litt. 2005, Dvorak et al. 2019). The population is therefore considered stable over the last three decades (J. Freile in litt. 2018, Dvorak et al. 2019).
Mimus melanotis is endemic to the island of San Cristóbal in the central Galápagos islands, Ecuador (Sibley and Monroe 1990).
The species is widespread across all habitat types on the island from lowlands up to the island summit at 730 m, including farmland, woodland with scattered trees of native Miconia or introduced guava, as well as scrub woodland and cactus scrub (Dvorak et al. 2019). Population densities were found to be highest in dry habitats (Dvorak et al. 2019). It tends to avoid dense lowland forest, taller, wetter woodland, grassland and urban areas (Cody 2004). The species forages on the ground for arthropods, also taking fruit and berries and occasionally picking ticks (Acarina) off marine iguanas (Amblyrhynchus spp.). It breeds in January to April, apparently not cooperatively, in contrast to other Nesomimus spp. (Cody 2004).
The original vegetation on San Cristóbal is highly degraded and disturbed, mainly through overgrazing by goats, human settlements and the introduction of non-native plants (Psidium guajava, Syzygium jambos, Rubus niveus) and animals (e.go. Black Rats Rattus rattus and feral cats Felis catus) (Curry 1989, Vargas 1996, Dvorak et al. 2019). Moreover, the nestling parasite Philornis downsi is present on the island (Wiedenfeld et al. 2007, Bulgarella et al. 2019). A number of disease vectors have been introduced, including Culex quinquefasciatus (vector of avian malaria) and Simulium bipunctatus (Peck et al. 1998, Vargas and Bensted-Smith 2000, Whiteman et al. 2005), and chickens on the growing number of chicken farms have brought in new diseases and may act as intermediary hosts (Gottdenker et al. 2005). The incidence of parasites and diseases could be more important in the future with the increase in frequency and intensity of El Niño events and the more humid conditions in the islands (H. Vargas in litt. 2005, Wiedenfeld et al. 2007). Nevertheless, the high density and stable population of San Cristobal Mockingbird suggest that the species is able to adapt to and tolerate these conditions.
Conservation Actions Underway
The Galápagos National Park was gazetted in 1959, and includes almost all the land area of the islands. In 1979, the islands were declared a World Heritage Site (Jackson 1985). Several small-scale habitat restoration projects are carried out across San Cristóbal (Dvorak et al. 2019). Populations of introduced mammals, including goats, donkeys and cattle, were reduced on the island; projects to sterilise feral cats and dogs are ongoing (Dvorak et al. 2019).
25-26 cm. Large mimid, greyish-brown above and pale below, with prominent black lores and blackish ear patch. Sexes similar, female c. 10% smaller than male in linear measurements. Juvenile is more streaked below than adult. Voice Loud, melodious and disjointed territorial song, typical of other members of its genus.
Text account compilers
Butchart, S., Curry, R., Ekstrom, J., Fessl, B., Freile, J., Gilroy, J., Harding, M., Sharpe, C.J., Temple, H., Vargas, H. & Wiedenfeld, D.
BirdLife International (2022) Species factsheet: Mimus melanotis. Downloaded from http://www.birdlife.org on 20/01/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 20/01/2022.