Sunbird got their name from the brightly with iridescent or rainbow like colours plumage (mostly in male species)
The colours of the iridescence changes with the angle of incident light such that a blue may suddenly appear green or black.
and finally flew away with the catch.
Their primary food is nectar, but it also eats small fruits and berries.
This male bird was bringing the spider to its chicks, because chicks and juveniles need high protein.