I arrived very early at the Matang Mangrove Forest Reserve, Perak on 2nd February 2023; it was still dark at 7.00am. There was a male Large-tailed Nightjar (Caprimulgus macrurus) calling out while perched on the electrical wires, with some street lights nearby. The Nikon Z9 camera I use has an electronic viewfinder that allows for the brightness levels to be set higher. This enables good observation in very low light settings. I noticed that the throat and neck of the bird would get considerably distended when calling. I used high ISO settings (51200) to document this (see image, cleaned using Topaz Denoise).
In addition, the white throat patch would be expressed better as the bird called out.
There was a female Large-tailed Nightjar watching nearby. The calls made were those I have previously observed as part of courtship behaviour (Amar-Singh HSS 2019). A call recording I made from Matang Mangrove Forest Reserve, Kuala Sepetang, Perak can be heard here: https://xeno-canto.org/778223
Once the series of calls was completed the pair flew off together.
I wonder if the white throat patch that ‘flashes’ as the bird calls (much better appreciated in person) is part of the courtship display? It is a feature that can be appreciated in low light, especially by these nocturnal birds.
Amar-Singh HSS (2019). Large-tailed Nightjar – courtship calls. Bird Ecology Study Group. https://besgroup.org/2021/12/17/large-tailed-nightjar-courtship-calls/
Dato’ Dr Amar-Singh HSS
Ipoh, Perak, Malaysia
Note to readers: If you like this post please tap on the Like button at the left bottom of page