Great-tailed Grackle, Quiscalus mexicanus

Great-tailed Grackle, Quiscalus mexicanus mexicanus, Female. Bird photographed in Parque National Huatulco, Huatulco, Oaxaca, March 2021. Photograph and identification courtesy of Marina Sutormina, Stockholm, Sweden.

Great-tailed Grackle, Quiscalus mexicanus mexicanus, Female. Bird photographed in greater Mexico City area, March 2021. Photograph and identification courtesy of Marina Sutormina, Stockholm, Sweden.

Great-tailed Grackle, Quiscalus mexicanus loweryi, Male. Bird photographed in the greater Yal-Ku area, Quintana Roo, April 2017, March 2018. Photography courtesy of Juan Rojo, Akumal.

Great-tailed Grackle, Quiscalus mexicanus monsoni, Female. Photograph taken in Huatabampo, Sonora, December 2017. Photograph and identification courtesy of David F Smith, Alamos, Sonora.

Great-tailed Grackle, Quiscalus mexicanus obscurus, Male. Bird photographed in the greater Zihuatanejo area, Guerrero, March 2019. Photograph courtesy of Ron Woheau, Zihuatanejo.

Great-tailed Grackle, Quiscalus mexicanus mexicanus, Male. Bird photographed in the greater Mexico City area, March 2021. Photograph and identification courtesy of Marina Sutormina, Stockholm, Sweden.

Great-tailed Grackle, Quiscalus mexicanus mexicanus, Male. Bird photographed in Parque National Huatulco, Huatulco, Oaxaca, March 2021. Photograph and identification courtesy of Marina Sutormina, Stockholm, Sweden.

Great-tailed Grackle, Quiscalus mexicanus nelsoni, Female. Bird photographed on the Oceanside Pier, Oceanside, California, May 2018.

Great-tailed Grackle, Quiscalus mexicanus nelsoni, Male. Bird photographed on the Oceanside Pier, Oceanside, California, May 2018.

Great-tailed Grackle, Quiscalus mexicanus nelsoni, Male. Photograph taken within a residential community in Alamos, Sonora, April 2018. Photograph and identification courtesy of David F Smith, Alamos, Sonora.

Background and Identification

The Great-tailed Grackle, Quiscalus mexicanus loweryi, Quiscalus mexicanus mexicanus, Quiscalus mexicanus monsoni, Quiscalus mexicanus nelsoni, and Quiscalus mexicanus obscurus, are five of eight subspecies of Great-tailed Grackle, six of which are found in Mexico. They are a member of the Icteriidae Family of Troupials and Allies that includes Grackles, New World Blackbirds and Orioles, that has one hundred five members placed in thirty genera, and one of seven global species of the Quiscalus Genus. In Mexico they are known as zanate mayor and zanate mexicano.

The Great-tailed Grackle is large in stature. They are sexually dimorphic and easily separated. The adult males are a uniform glossy black with a purple iridescent sheen with yellow eyes; the females are about half the size of the males and are tan to dark brown with off white eyes. They have a long keel-shaped tail, a massive bill, yellow eyes and black legs and feet The males have a large and varied vocal repertoire and are known for their elaborate courtship and territorial displays.

Habitat and Geographical Range

The Great-tailed Grackle are found in in dry coastal habitats that have scattered trees and thickets in open and semi-open country near standing water at elevations up to 2,300 m (7,500 feet) but normally at lower altitudes. Inland they are found in prairies, agricultural areas and in towns. They are year-round residents and non-migratory. They forage mostly on ground trees, and shrubs, and by wading in water, in large single-sex flocks during non-breeding season that include numerous other icterids. They feed on other birds and bird eggs, berries, a wide variety of crustaceans, small fish, fruits, grains, insects, nuts, vertebrates, and emerging agricultural crops; they are also known to cannibalize nestlings. Reproduction is polygynous with the males establishing and defend small territories, nestlings, and fledglings from potential predation while the females care for the young. The males have a high mortality rate and most adult populations are predominantly female. They have life spans of up to thirteen years.

The Great-tailed Grackle is found throughout Mexico with the exception that they absent from most of Baja California and from Baja California Sur. In Mexico the loweryi subspecies is found within the Yucatan Peninsula and close offshore islands; the obscurus subspecies from Nayarit south to Guerrero; the mexicanus subspecies from eastern Jalisco and San Luis Potosí south to Guatemala; the monsoni subspecies within northeastern Baja California and northwestern Sonora, and, the nelsoni subspecies in the extreme northern sections of Baja California and Sonora.

Common Misidentifications