This Chilean endemic is a primary vector for the bright red leafless Quintral Mistletoe (Tristerix aphyllus) which parasitizes the Quisco Cactus (Echinopsis chiloensis). The mockingbird specializes in the mistletoe fruit and transfers its seeds to the cactus in its feces. Photos of the cactus and the mistletoe here. Populations such as this, in the northern part of their range average paler and grayer than those further south, but no subspecies have yet been described. Canon PowerShot SX50 HS.
References:
Botto-Mahan, C., Medel, R., Ginocchio, R. and Montenegro, G. (2000) Factors affecting the circular distribution of the leafless mistletoe Tristerix aphyllus (Loranthaceae) on the cactus Echinopsis chiloensis. Revista Chilena de Historia Natural, 73: 525 - 531.
Chilean Mockingbird (Mimus thenca), In Neotropical Birds Online (T. S. Schulenberg, editor). Cornell Lab of Ornithology, Ithaca, New York, USA. retrieved from Neotropical Birds Online: https://neotropical.birds.cornell.edu/Species-Account/nb/species/chimoc1
Cody, M. (2018). Chilean Mockingbird (Mimus thenca). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/58193 on 14 February 2018).