It has been raining daily here in Vung Tau for almost two months now (without flooding, or rather, "water accumulation" as it's being called in Saigon. How do you like them apples, dear Ministry of Construction?)
With every rainfall in the daytime, dozens birds of a particular type are out frolicking in the sky instead of hiding on the trees. They fly in wide circles, crisscrossing one another and having a merry time until the rain stops, then they disperse.
They're on the small side but not too small, black in colour, perhaps with a paler underbelly but perhaps not. They're very fast, very energetic both in and out of the rain. I've been doing quite a bit of research but couldn't find the descriptions match any rain-loving birds in Asia and Oceania.
Is anyone familiar with those birds?