tree fork, while nests of griseobarbatus are cup-shaped structures built out of dry weeds, vines, and bark and lined with black lichen, feathers, and seed down. The nests of griseobarbatus had an external height and depth of 50 mm and 77 mm, with an internal height and depth of 31 mm and 52 mm. Eggs are laid in clutches of 2–4 at a time. Eggs vary in appearance and size between different subspecies. The mean size of eggs in griseobarbatus is reported to be , while that size of eggs in Brazil is , and the size of eggs in Argentina being . The average mass of eggs measured in southeastern Brazil was . Eggs of vividior are white with some blackish spots on the larger end of the egg. Eggs of griseobarbatus are said to be white with sparse and faint markings. Eggs in eastern Brazil have been described as white. The eggs in northeastern Argentina have been described as being white and having gray or fine chestnut markings and dark lines which were concentrated at the larger end. The incubation period of the eggs is reported as being 10–16 days. Only females incubate the eggs. The nests are probably parasitized by shiny cowbirds. Eggs might also be eaten by snakes as one nest in Ecuador was observed being predated on by a snake. The nestling period is 10–13 days, and young are dependent on parents for a while after they have fledged. Status The chivi vireo is listed as a least concern species by the IUCN. The species is common across its large range, and seems to have a stable population. The population may also be increasing locally. Also, its acceptance of disturbed habitat increases its chances of survival. References Vireo (genus) Birds described in 1817 Taxa named by Louis Jean Pierre Vieillot