The Large-tailed Nightjar (Caprimulgus macrurus bimaculatus) that initially lived in our immediate neighbourhood and, for the past 2 years, has lived in our garden, is probably the bird we have watched the most. Apart from frequent daytime observations, we also get to watch night time behaviour before our bedtime and especially when we have breakfast on our roof in the early mornings (4.30-5.30am).
One interesting observation is courtship calls – when the pair is courting they will make low pitched growling calls to each other as part of the bonding process. These are very different from the loud, classical “chock-chock” calls. The mutual-growling-courtship activity can carry on for long periods. In one 50 second continual recording, I counted 120 vocalisations (2.4 per second, counting only the louder partner, recorded at 5.30am). Amplified recording here: https://www.xeno-canto.org/474400 – you have to listen intently to hear the partner vocalising almost simultaneously in the ‘background’. The sonogram in the post shows how low pitched the calls are at 1-2.5 kHz. I have intentionally chosen this section of calls to display because the partner’s calls are occasionally separated. Usually the calls are merged but when the first caller pauses briefly you can hear and identify the other bird’s calls (see image).
Amar-Singh HSS (Dato’ Dr)
Ipoh, Perak, Malaysia
Habitat: Wild urban garden