Scarlet-rumped Cacique

Cacicus microrhynchus

km58 Valle Del Cauca Colombia

Quick Facts

  • Scientific Name: Cacicus microrhynchus
  • Spanish Name: Cacique lomiescarlata
  • Family: Icteridae
  • Known Nicknames: Northern Scarlet-rumped Cacique, Small-billed Cacique
  • Average Length: 23–27 cm / 9–10.6 in
  • Average Weight: 57–68 g / 2.0–2.4 oz
  • Wingspan: 35–42 cm / 13.8–16.5 in
  • Key Feature: Glossy black plumage with a vivid scarlet-red lower back and rump, and a pale ivory-colored bill
  • Primary Diet: Omnivore (Insects, fruit, and nectar)
  • Range: Central America (Honduras to Panama) and the Pacific lowlands of Colombia and Ecuador
  • Habitat: Humid lowland forests and older secondary growth
  • Social Structure: Social; often travels in small family groups and nests in small colonies
  • Nesting/Breeding: Pouch-like pendulous nests woven from plant fibers hanging from high branches
  • Conservation Status: Least Concern (LC)
  • Population Trend: Decreasing

The Scarlet-rumped Cacique (*Cacicus microrhynchus*) is a striking, medium-sized songbird of the humid tropical lowlands, instantly recognizable by its sleek, jet-black plumage and the brilliant scarlet patch on its lower back that gives the species its name. While this vibrant red rump is often hidden by its wings at rest, it flashes like a beacon during flight or social displays, contrasting sharply with the bird’s piercing, pale blue eyes and ivory-colored, chisel-like bill. Beyond its bold appearance, this social member of the icterid family is celebrated for its architectural ingenuity, weaving long, pendulous nests that dangle like teardrops from the forest canopy, and for its remarkably complex vocalizations, which range from liquid whistles to mechanical chattering that echoes through the rainforest.

Fun Facts

The Scarlet-rumped Cacique is a master of deception and defense, often building its long, hanging pouch nests near active wasp colonies to use the stinging insects as a natural security system against predators. These birds are remarkable mimics, capable of imitating the complex songs of other bird species and even the sounds of local mammals. While their plumage appears mostly black, they possess a brilliant, fiery-red patch on their lower back that remains hidden until they take flight, creating a sudden and dramatic flash of color. Furthermore, during courtship, males perform elaborate displays that involve deep bowing and rhythmic wing-spreading to showcase their vibrant rumps to potential mates.

Habitats & Distribution

This species is native to Central and South America, with a geographical range extending from Honduras and Nicaragua southward through Costa Rica and Panama into western Colombia and western Ecuador. It primarily inhabits humid lowland regions, typically found at elevations from sea level up to approximately 1,000 meters, though it may occasionally occur in lower montane forests. The preferred environments include the canopy and edges of dense tropical rainforests, as well as mature second-growth forests and semi-open woodlands. It is frequently observed in transitional areas where the forest meets clearings or riverbanks, and it can also adapt to living in shaded plantations and tall, shrubby thickets near water sources.

Behaviours & Reproduction

These birds are highly social and typically forage in small, active groups or alongside mixed-species flocks. During the breeding season, they exhibit a polygynous mating system where dominant males mate with multiple females within a colony. They are colonial nesters, with females weaving long, pendulous pouch-like nests from plant fibers, vines, and grasses. These structures are often suspended from the tips of thin branches to provide a physical barrier against arboreal predators such as monkeys and snakes. A unique reproductive strategy involves building nesting colonies in close proximity to the nests of aggressive social wasps. This commensal relationship offers protection, as the wasps deter both predators and parasitic botflies that might harm the chicks. While the female is solely responsible for constructing the nest and incubating the two to three eggs, the male focuses on defending the colony’s territory and performing complex vocal displays to maintain his social standing and attract additional mates.

Diet

The Scarlet-rumped Cacique is primarily an omnivore whose diet consists of a diverse array of insects, small invertebrates, fruits, and nectar. These birds are energetic foragers that typically inhabit the middle and upper canopy, where they search through foliage, epiphytes, and clusters of dead leaves for prey such as spiders, beetles, and caterpillars. A particularly fascinating aspect of their feeding strategy is their use of a technique known as "gaping," where they insert their pointed bills into crevices or rolled leaves and then pry them open to expose hidden insects. Beyond their reliance on animal protein, they are frequent visitors to fruiting trees and have been observed drinking nectar from large flowers, a habit that can inadvertently assist in the pollination of certain tropical plant species. Their opportunistic nature also leads them to occasionally follow army ant swarms to capture insects fleeing from the ants, demonstrating a highly adaptable approach to finding food in a competitive rainforest environment.

Colors

The Scarlet-rumped Cacique is characterized by its uniform glossy black plumage, which contrasts sharply with a vibrant scarlet patch on its lower back and rump. It features a pale ivory or bluish-white pointed bill and striking pale blue eyes. This bold, high-contrast coloration is used primarily for social signaling and species recognition within dense tropical foliage rather than for camouflage.