The thick-billed parrot is about 15 inches (38 centimeters) long from head to tail. It is a bright green bird with a red forehead and red patches at the crook of the wing and thigh.
Its eyes are marked with a small brownish spot and it has yellow sections under its wings and gray feathers on its lower surfaces. It has gray legs and feet and its thick bill is black.
Thick-billed parrots feed mainly on the seeds of pine trees, shredding the pinecones of a variety of conifers (evergreen trees and shrubs) in order to extract the seeds.
They also eat acorns, juniper berries, flower nectar, insects, and tree bark. They hunt during the day and sleep in their roosting places high in the pine trees at night.
Thick-billed parrots live in flocks, which may be as small as seven or eight members or they may be comprised of a thousand or more birds. They are strong flyers, often forming a V or other formation when they fly. The birds are noted for their loud screeching calls, which can be heard from great distances.
Thick-billed parrots breed from July through September, nesting in cavities of trees at high elevations. The female lays from two to four eggs, with spaces of one or two days between each egg.
While she incubates the eggs (sits on them to keep them warm), the male goes off during the day to get food and bring it back to her. About 26 to 28 days later the eggs hatch, one at a time, as they were laid.
The chicks will have their full plumage (feathers) within 56 days of their birth and they will fly shortly thereafter. The parents remain with them up to about seven months, continuing to feed them as they instruct them how to extract seeds from pinecones for themselves.
Thick-billed parrots live under constant threat from predators. When they feed, they often have one bird in the flock standing watch for predators, ready to signal to the other birds the moment an enemy is spotted. Their main enemies are raptors (birds of prey), such as red-tailed hawks, Apache goshawks, and peregrine falcons. When they are roosting in the trees they are also preyed upon by ring-tailed cats.
Habitat and current distribution
Thick-billed parrots spend the nesting season in the conifer forests of the northern Sierra Madre Occidental Mountains, mainly in the states of Durango and Chihuahua in northern Mexico. After the breeding season, the birds form flocks and migrate south. They prefer to nest and roost at high elevations, above 6,500 feet (1,981 meters).
An estimated population of 500 to 2,000 pairs (male and female partners) survives today.
History and conservation measures
The species continued to live in its main habitat in Mexico, but during the last decades of the twentieth century, the extensive logging in the Sierra Madre Occidental Mountains greatly reduced the population in Mexico. Thick-billed parrots are also captured for trade as pets.
Numerous studies are underway in an attempt to determine how to save the thick-billed parrot as its habitat continues to diminish. The World Parrot Trust provides funding to groups that attempt to determine the species’ habitat requirements and study the effects of moving the birds to a new habitat.
The Instituto Tecnologico de Estudios Superiores de Monterrey, in Nuevo Leon, Mexico, in collaboration with the U.S. Fish and Wildlife Service, has provided funds to protect the breeding range of the thick-billed parrot in Nuevo Leon, Mexico, through the development of management plans and training.
Because of the dangers posed by trade in the pet market, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listed the thick-billed parrot on its Apendix 1, which includes species threatened with extinction. This listing makes trade of the species subject to particularly strict trade regulations, authorized only under “exceptional circumstances.”