Mistaken identity

I keep getting two birds mixed up. The first in an Asian Koel and the second is the Asian Glossy Starling. Both are black and both have red eyes. The main difference as far as I can tell is that the feathers of the Asian Glossy Starling has a greenish hue to it. But I didn't notice this until recently so I kept mixing them up. I have seen both in my old JC and some are definitely Koels. Koels have a very distinctive and unfortunately loud call. It's name is derived from its call and sounds like Koooeeel! You tend to notice this call when the said bird is right above your head. Boy! Ain't it loud. In some places, the bird calls in the wee hours of the morning. I can imagine that the residents in those area would be less happy then me to find a Koel in their backyard. I have heard complaints about being woken up by the bird's call. Some people, including my dad, find the call spooky. Perhaps the reason I don't is that I know the bird behind it. Still, I do find it annoying. I have told the bird to shut up several times. Needless to say, it usually doesn't listen to me.

 This bird is an Asian Glossy Starling. Unfortunately, I have yet to take a picture of a Koel. Notice the greenish hue of the feathers? That's how you tell these two birds apart. As for these birds on the left, I took them eating on the oil palm in my old school. They were good and obliging photo subjects. Or in other words they didn't move too much. Wish more of the butterflies I took were as obliging. I must have spent ages chasing them down.

May

P.S. I just took a look at the internet and the Asian Koel also has a paler, more greyish beak that isn't black unlike a Asian Glossy Starling's. Boy! If I only I had known earlier. That is a lot easier to spot! So slight emendation to my statement earlier about the main difference between these two birds. The main difference is the beak colour and not the greenish hue of the feathers.