Difficulty of observing nesting behaviour

We changed to a new observation spot today. The nest is located at the left branch where it was snapped off when mainteinance workers at the garden accidentally broke it. Thankfully, it didn't affect the nest cavity and the adult pair successfully reared one fledgling. Nevertheless, the physical changes done to the nest may render it a poor nest from now on; therefore, we are thinking off sawing it off (to examine it closely) if no pair is using it one month after the fledgling leaves the nest.

One difficult task of observing any new site is to differentiate adult A from adult B, and preferably know the correct gender of each. Sadly, after a few hours of looking at them (below photos), we were not able to point out any significent characteristics. Hence, the set-up of a triangle mist nest outside the nest (right photo above) to try and capture the adults and leg-band them.

Are they the same or different individuals?

We successfully caught one adult just a few minutes after setting the net up. We completed the measurements and leg-banding within an hour and released it soon afterwards. We then waited for more than four hours for the other adult to arrive. Strangely, that never happened. We will have to try again tomorrow. Maybe it is a single-parent family?

While waiting during the four-hour period, I saw two Malay Night Herons near us - probably because there was a nest with two fledglings just a few metres above us. When a stray cat passed by the adult, the adult heron raised its head feathers and became very fierce-looking.

My co-worker pointed out this hidden nest of Chinese Bulbul (Pycnonotus sinensis) for me to see and photograph (while the parents are away).

Beautiful orbs.

PS - When we checked the nest with the abandoned fledgling today, we saw a lifeless body. We were too late. Truthfully, rescuing it was quite challenging for us too since we were unsure how to get the baby bird from the nest chamber 25- to 30-cm deep from the nest entrance that is only about 5-cm in diameter. We are truly sorry and may you rest in peace, baby barbet.
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