Cyanocorax yncasgreen jay(Also: Inca jay)

Ge­o­graphic Range

There are two dis­tinct pop­u­la­tions of the Green Jay. The first is found north of the Rio Grande river in south­ern Texas to north cen­tral Hon­duras. The sec­ond pop­u­la­tion stretches from Colom­bia and Venezuela south through east­ern Ecuador and Peru to Bo­livia.

Habi­tat

The Texas Green Jay prefers open wood­land, dense sec­ondary growth, and bushy thick­ets dom­i­nated by mesquite. This jay is also found in cit­rus groves. Mid­dle Amer­i­can pop­u­la­tions pre­fer humid forests, rain forests, low­lands, plan­ta­tions, and moun­tains. In South Amer­ica the Green Jay is found in humid mon­tane for­est and for­est bor­ders, clear­ings, and sec­ondary wood­land.

Phys­i­cal De­scrip­tion

The Green Jay is a long-tailed bird with a short crest. It is sim­i­lar in size to a Blue Jay. Its wings, how­ever, are shorter and more rounded. The Texas Green Jay has stiff, short deep blue nasal and frontal plumes. Its fore­head, crown, and nape are white to bluish white. The feath­ers of the man­tle, back, rump, and up­per­tail-coverts are deep green and some­times tinged with blue. The breast and re­main­ing un­der­parts are yel­low to yel­low-green. In­di­vid­u­als from South Amer­ica are a lit­tle larger and with longer nasal and frontal plumes that form a bushy crest.

Re­pro­duc­tion

The Green Jay prac­tices monogamy, and pairs may form at any time dur­ing the year through the re­pla­cent­ment of an ab­sent breeder. Dur­ing the breed­ing sea­son, a breed­ing pair rarely parts. Nests are usu­ally in dense thick­ets, and trees and bushy shrubs are com­mon nest­ing sites. Both the male and the fe­male par­tic­i­pate equally in choos­ing the nest site and build­ing the nest. In Colom­bia, other mem­bers of a flock have oc­cas­sion­ally been seen to par­tic­i­pate in con­struct­ing the nest. The nest is cupped and its thin walls en­able the eggs in­side to be seen from below. Green Jay nests are con­structed of thorny twigs and sticks and lined with roots, stems, moss, or dry leaves. Av­er­age clutch size is four gray­ish-white oval eggs. In­cu­ba­tion is per­formed only by the fe­male and lasts 17 days. In Texas pop­u­la­tions, the fe­male is fed by the male at least six times a day. In South Amer­i­can pop­u­la­tions, the fe­male is fed by her mate; how­ever, dur­ing the last three days of in­cu­ba­tion she is fed by other flock mem­bers. After the chicks have hatched, the male con­tin­ues to bring food to the nest for five days, then both par­ents share equally in bring­ing food to the chicks. Once the chicksd leave the nest, the fe­male con­tin­ues to feed them for three weeks. In Columbian flocks, all mem­bers co­op­er­ate in bring­ing food to the young and con­tinue feed­ing the chicks for at least 20 days after they leave the nest.

  • Average eggs per season
    4
    AnAge

Lifes­pan/Longevity

Be­hav­ior

Texas pop­u­la­tions are non­mi­gra­tory; how­ever, there is a pos­si­bil­ity of local mi­gra­tion in the Hon­duras pop­u­la­tion. The south­ern Texas pop­u­la­tion of Green Jay dis­plays un­usual be­hav­ior as it re­tains re­lated non­breed­ers in fam­ily flocks with­out co­op­er­a­tive breed­ing (helpers at the nest). These Texas flocks con­tain a breed­ing pair, the cur­rrent year's nestlings, and the one year old non-breed­ing jays from the pre­vi­ous breed­ing sea­son. The one year old nestlings pro­vide ter­ri­to­r­ial de­fense, but are ejected from flock when the cur­rent sea­son's chicks have fledged. Colom­bian flocks have fixed year-round mem­bers that in­clude helpers at the nest. Helpers at the nest may be needed in Colom­bia be­cause food is less abun­dant due to habi­tat sat­u­ra­tion. Usu­ally, the more helpers a flock has, the higher the surv­ior­ship of its fledg­lings.

Com­mu­ni­ca­tion and Per­cep­tion

Food Habits

Green jays are om­niv­o­rous. Their basic diet con­sists of arthro­pods, ver­te­brates, seeds, and fruit. The bird for­ages in fam­ily flocks by ex­am­in­ing new sur­round­ings after hop­ping or short flights. When for­ag­ing, the bird moves from the lower por­tion of a tree in a spi­ral fash­ion up to the branches. The jay ocas­sion­ally hov­ers to in­spect slen­der branches and clumps of moss. When for­ag­ing on the ground as an in­di­vid­ual, it turns over dry leaves and twigs by sweep­ing its bill from side to side.

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

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Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

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Con­ser­va­tion Sta­tus

The Green Jay holds no spe­cial sta­tus, but pop­u­la­tions are lim­ited by the amount of breed­ing habi­tat avail­able. The bird is also vul­ner­a­ble to traps set for other an­i­mals. The ef­fects of trap­ping can be can be re­duced by clos­ing the traps at dusk or check­ing them at fre­quent in­ter­vals.

Other Com­ments

The Green Jay has a va­ri­ety of calls, and flocks are often noisy and con­spic­u­ous in the breed­ing sea­son. The species re­mains rel­a­tively un­stud­ied.

Con­trib­u­tors

Marie S. Har­ris (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

visual

uses sight to communicate

Ref­er­ences

Gayou, Dou­glas, C.. The Birds of North Amer­ica, No. 187, 1995.