Amblycercus holosericeusyellow-billed cacique

Geographic Range

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)

  • Range elevation
    200 to 1800 m
    656.17 to 5905.51 ft

Physical Description

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)

  • Sexual Dimorphism
  • male larger
  • sexes colored or patterned differently
  • male more colorful
  • Range mass
    56.7 to 70.9 g
    2.00 to 2.50 oz
  • Range length
    21.6 to 25.4 cm
    8.50 to 10.00 in
  • Average wingspan
    23 cm
    9.06 in


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)

  • Breeding interval
    Breeding intervals in yellow-billed caciques are not known.
  • Breeding season
    Breeding varies geographically, from November to April in much of South America, from January to June in Central America and Mexico.
  • Range eggs per season
    1 to 5
  • Range time to hatching
    26 to 30 days

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)

  • Parental Investment
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • male
  • post-independence association with parents


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

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

Communication and Perception

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)

  • Other Communication Modes
  • duets

Food Habits

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)

  • Animal Foods
  • insects
  • Plant Foods
  • fruit


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)

Ecosystem Roles

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

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

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

Economic Importance for Humans: Negative

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

Conservation Status

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)


Andrew Jordan (author), Centre College, Grant Wallace (author), Centre College, Stephanie Fabritius (editor, instructor), Centre College, Tanya Dewey (editor), Animal Diversity Web.



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

World Map


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.


uses smells or other chemicals to communicate

  1. active during the day, 2. lasting for one day.

to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate


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.

female parental care

parental care is carried out by females


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


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).


Having one mate at a time.


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.


an animal that mainly eats all kinds of things, including plants and animals


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

seasonal breeding

breeding is confined to a particular season


remains in the same area


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


lives alone


uses touch to communicate


Living on the ground.


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


uses sight to communicate


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Brown, W., S. Hilty. 1986. Birds of Colombia. Princeton, NewJersey: Princeton University Press.

Eaton, M. 2006. A Phylogenetic Perspective on the Evolution of Chromatic Ultraviolet Plumage Coloration in Grackles and Allies(Icteridae). Auk, 123/1: 211-234. Accessed April 03, 2009 at

Greeney, H., D. Jaffe, O. Manzaba. 2008. Incubation Behavior of the Yellow-billed Cacique. Ornitologíz Colombiana, 7: 83-87. Accessed April 07, 2009 at http://www.ornotologí

Kratter, A. 1993. Geographic Variation in the Yellow-billed Cacique, Amblycercus holosericeus. Condor, 95/3: 641-651. Accessed April 07, 2009 at

Lunk, W. 2009. Cacique. Groilier Multimedia Encyclopedia. Accessed April 07, 2009 at <>..

Ridgely, R., G. Tudor. 1989. The Birds of South America. Austin, TX: University of Texas Press.

Skutch, A. 1996. Orioles, Blackbirds, and Their Kin. Tuscon, AZ: The University of Arizona Press.

Stager, K. 2009. Cacique (bird). Encyclopedia Americana. Groiler Online. Accessed April 07, 2009 at

de Magalhaes, J., J. Costa. 2010. "AnAge" (On-line). AnAge: The Animal Ageing and Longevity Database. Accessed January 25, 2010 at