Amblycercus holosericeus
yellow-billed cacique

Yellow-billed caciques can be found throughout much of the neotropics. They are found in the Yucatan peninsula of Mexico, through Central America and into the mountainous regions of South America, including Colombia, Venezuela, Bolivia, and Ecuador. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986)

Yellow-billed caciques live at various elevations throughout their geographic range. Typically they are found at elevations of 200 to 1,800 m above sea level. They have been observed at elevations up to 6,000 m in Venezuela. (Skutch, 1996)

Yellow-billed cacique habitat consists of thick stands of overgrown brush in lower altitudes. In mountainous regions, they commonly seek refuge in large bamboo thickets that cover the forest floor. They commonly live deep inside thickets and brush in order to protect themselves from predators. ("New World Blackbirds and Orioles", 2002; Skutch, 1996)

Yellow-billed caciques are large song birds. The body is completely black in both males and females. Males, however, have a more lustrous shine to their feathers than females. Both sexes also have a characteristic beak which is a whitish-yellow color. Their eyes are vibrant yellow as well. They are different from other caciques in the fact that they are the only ones who are open-nest builders. That is, they build an open-topped, cup–shaped nest in which to lay their eggs. They range in size from 56.7 to 70.9 g and from 21.6 to 25.4 cm in length, males are slightly larger than females. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Lunk, 2009; Ridgely and Tudor, 1989; Skutch, 1996)

Yellow-billed caciques are seasonally monogamous. Males and females form a bond for the breeding season. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Kratter, 1993; Skutch, 1996)

Yellow-billed cacique breeding season varies geographically. Breeding season in Costa Rica is between the months of January and June. Eggs have been observed as early as December in Ecuador. Throughout much of South America mating takes place from November to April. Females lay from 1 to 5 eggs in a clutch. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Kratter, 1993; Skutch, 1996; Stager, 2009)

Nesting behavior also varies geographically. Populations that live in lowland areas in Central America have nesting behavior that is different from populations in mountainous regions of south America. Lowland populations tend to build their nests inside large, dense thickets of bamboo, which are nearly impassable and provide protection from predators. (Kratter, 1993)

Yellow-billed caciques defend nesting territories and care for their young until independence. Males mainly defend nesting territories and the young, while females mainly incubate and feed the young. When the female is away from the nest, the male guards it. ("New World Blackbirds and Orioles", 2002; Skutch, 1996)

Lifespan in yellow-billed caciques is not known, but other icterids live to maximum lifespans of from 6 to 20 years.

Solitary and sedentary in nature, yellow-billed caciques try to remain secluded in thickets and brush. They only travel out of thickets for food from high tree branches. They are different from other caciques in how they build their nests, which are built with an open cup shape. Nests are a combination of vines and leaf fibers woven together and are located off of the ground. Typically individuals are found alone, in a pair, or as part of small family groups during breeding season. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Skutch, 1996; "New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Skutch, 1996)

Home range sizes in yellow-billed caciques are not known.

Males and females communicate through song patterns known as duets. The male begins with a churring sound. The female responds with a distinct call. The female also will whistle and chip to alert the male of potential hazards to the nest (i.e. approaching predators). The male has a more melodic sound in its chirp than females do. (Ridgely and Tudor, 1989; Skutch, 1996)

Yellow-billed caciques are omnivorous. They feed generally on fruits, especially the seed pods of trees in the genus Inga. Yellow-billed caciques also use their sharp and narrow beaks to drill into bark and sugarcane stalks to search for various types of insects. They use special muscle groups to open their bills against pressure. This allows them to widen holes in order to remove any insects or seeds that they find. ("New World Blackbirds and Orioles", 2002; Lunk, 2009; Skutch, 1996)

Yellow-billed caciques have adapted to avoid predators in the way that they choose their habitat. They build their nests and spend most of their time inside thick stands of brush or bamboo, protecting them from many, larger predators. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Kratter, 1993; Lunk, 2009; Ridgely and Tudor, 1989; Skutch, 1996)

Yellow-billed caciques help to disperse the seeds of fruits they eat. ("New World Blackbirds and Orioles", 2002)

Yellow-billed caciques are important members of the ecosystems in which they live.

There are no known adverse effects of yellow-billed caciques on humans.

According to the IUCN Red List, Amblycercus holosericeus is considered "Least Concern." Yellow-billed caciques are found throughout a wide range and populations seem stable. ("New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Ridgely and Tudor, 1989; "New World Blackbirds and Orioles", 2002; Brown and Hilty, 1986; Ridgely and Tudor, 1989)