Silvery-throated jay
The silvery-throated jay is a species of bird in the family Corvidae, the crows and jays. It is found in Costa Rica and Panama.
Taxonomy and systematics
The silvery-throated jay was originally described in 1875 as Cyanocitta angentigula. It was later reassigned to its present genus Cyanolyca that had been erected in 1851.
The silvery-throated jay has two subspecies, the nominate C. a. argentigula and C. a. albior.
Description
The silvery-throated jay is long and weighs an average of. The sexes have the same plumage. Adults of the nominate subspecies have a mostly black head with a pale grayish lavender or silvery white band on the forecrown and rearward as a supercilium to the back of the ear coverts. Their upper back is black and their lower back, scapulars, rump, and uppertail coverts are dusky purplish blue. Their wings and tail are blue. Their throat and upper breast are pale lavender or silvery white. They have a black band across the lower breast that becomes dusky purplish blue on the belly and undertail coverts. Subspecies C. a. albior has a pure glossy white forecrown-supercilium strip with no lavender and a whiter throat and upper breast than the nominate. Juveniles have a faint or no stripe on the face and their crown is dusky purplish blue. Both subspecies have a dark brown to dark red iris, a black bill, and black legs and feet.
The only similarly patterned jay is the white-throated jay, which is endemic to Mexico.
Distribution and habitat
The silvery-throated jay has a disjunct distribution. Subspecies C. a. albior is the more northerly of the two and has the smaller range. It is found in central Costa Rica's Cordillera Central. The nominate subspecies is found in the Cordillera de Talamanca from southern Costa Rica into western Panama's Chiriquí Province. The silvery-throated jay inhabits montane evergreen forest in the subtropical and lower temperate zones. Its habitat also includes oak forest, and it occurs in both the forest interior and on its edges. In elevation it ranges between in Costa Rica and between in Panama.
Behavior
Movement
The silvery-throated jay is a year-round resident.
Feeding
The silvery-throated jay's diet is not known in detail but includes arthropods, small vertebrates like lizards and salamanders, and fruits. It forages in single-species flocks that in the non-breeding season may number up to 30 individuals. It forages mostly in the forest subcanopy and canopy but lower at the edges, moving deliberately and searching foliage, bromeliads, and mossy branches for prey.
Breeding
The silvery-throated jay's breeding season has not been fully defined but appears to span at least March to June in Costa Rica. Nothing else is known about the species' breeding biology.
Vocalization
The silvery-throated jay's principle vocalization is a "harsh nyah-nyah-nyah-nyah". It is also described as "a harsh, nasal, somewhat scratchy jew-jeah-jeah" and "a moderately loud, nasal chaak, cheuk, cheh". It scolds with "a harsher zhraaak" and gives a sharper "nyat nyat nyat" when taking off into flight.
Status
The IUCN has assessed the silvery-throated jay as being of Least Concern. It has a small range; its estimated population of between 20,000 and 50,000 mature individuals is believed to be stable. No immediate threats have been identified. It is considered very uncommon in Costa Rica.