The Cocos tyrannulet, also known as the Cocos flycatcher, is a vulnerable species of bird in subfamily Elaeniinae of family Tyrannidae, the tyrant flycatchers. It is endemic to Cocos Island off Costa Rica.
Region
Eastern Tropical Pacific (Cocos Island)
Typical Environment
Restricted to the forested habitats of Cocos Island, including humid evergreen forest, secondary growth, and edges. It frequents streamside thickets, clearings, and coastal scrub near the ranger station. The species forages from the understory to mid-canopy but also uses open gaps to sally for prey. Despite its small range, it is adaptable to a variety of wooded microhabitats on the island.
Altitude Range
Sea level to 575 m
Climate Zone
Tropical
Ease of Keeping
Beginner friendly: 1/5
Also called the Cocos flycatcher, this tiny tyrant flycatcher is found only on remote Cocos Island, Costa Rica. It is listed as Vulnerable due to its very small range and susceptibility to invasive predators and habitat changes. It often forages close to people around the island’s station clearings, making it one of the most frequently seen landbirds there.
Illustration by Charles Haskins Townsend
Temperament
active but unobtrusive
Flight Pattern
short rapid wingbeats with brief sallies
Social Behavior
Usually seen singly or in pairs, maintaining small territories. Pairs likely remain together through the breeding season and defend nest areas. The nest is a small cup placed in shrubs or low trees, and both parents participate in care. Outside breeding, it can join loose mixed-species foraging groups.
Migratory Pattern
Resident
Song Description
A thin, high-pitched series of tsee and tseet notes, often delivered in short sequences from a low perch. Calls include sharp chips and soft trills used during foraging and pair contact.
