Monsoon heralds the breeding season for many birds in Western Ghats, including the Iora. Roughly the size of a bulbul, the male takes on a bright yellow color and dons a glossy black mantle on its back. The female is pale greenish.
Yesterday saw a pair of these on a guava tree. They were busy picking up scraps of the loose bark. When a beak load was collected, the bird would disappear in the direction of the nest building site. This activity went on for atleast an hour. After that, I moved on..
I found this picture of an iora, here