Silky-tailed Nightjar Antrostomus sericocaudatus

  • Order: Caprimulgiformes
  • Family: Caprimulgidae
  • Polytypic: 2 subspecies
  • Authors: F. A. Wilkinson Wilkinson
Sections

Behavior

Behavior

Primarily crepuscular. Forages shortly after dark, by making make short, rapid sallies of 2-3 m from the same perch used for singing (Alexio et. al. 2000).

Both adults share incubating and brooding duties with the female on the nest during the day and the male on at night. Nest relief occurs between 0300–0600 and 1800–2100 hrs. No elaborate nest-relief ceremony takes place but breeding pairs often communicate by counter-calling with a full call or communicate with a one-note high pitched “sweet” call (Wilkinson 2009) prior nest-relief during incubation and brooding. The nesting adult calls directly from the nest and waits until its mate responds by calling or the mate calls in the distance and continues to call as it moves towards the nest and waits for the nesting adult to respond with a full or one-note call.

Self Defense – As with most members of the caprimulgid family, the Silky-tailed Nightjar often injury-feigns when disturbed from the nest during incubation and brooding; intensity increases during brooding. Nesting adults at CCBS aligned themselves parallel to the trail, facing a continual stretch of open area and tended to readily flush when an intruder approached within 10 m or if the intruder remained stationary near the nest for more than 5 mins. When flushed, adults would either just fly off to a nearby area or they would fly to open areas on the ground or to low branches (0-7 m), droop one or both wings, and quietly, yet rapidly, flap wings up and down while detracting the intruder away from the nest a few meters at a time (Wilkinson 2009). The amount of injury-feigning decreased as the distance between the intruder and the nest increased.

Territoriality

Silky-tailed Nightjars appear to exhibit strong site fidelity. Breeding pairs at CCBS have relatively large nesting sites (core areas that are frequently used based on nests and calls) ranging from 5.84-10.60 ha; some have been occupied for up to 10 years (Wilkinson 2009).

Sexual Behavior

No information. Appears to be monogamous throughout the breeding season.

Social and interspecific behavior

Information needed. Contribute

Predation

Response to predation – Adults have a tendency to abandon their nest after being flushed once or multiple times from the nest. Each time, they leave the eggs exposed for longer periods (sometimes up to 12 hrs) and the nest is eventually depredated upon (Wilkinson 2009). No known documentation of predation on adults or chicks.

Recommended Citation

Wilkinson, F. A. W. (2011). Silky-tailed Nightjar (Antrostomus sericocaudatus), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/nb.sitnig1.01