It is a Black-crowned Night Heron. You are right that the red eye is a good indicator, but this can be difficult to notice so also look for the overall grey-brown plumage, darker cap, thick bill and short, thick neck.
It's not a juvenile, which would be browner with pale spots on the wing coverts. This rather plain grey-brown plumage with a darker cap indicates a first-summer bird, i.e. a bird that hatched last year (2013). Author: samchang Time: 9/09/2014 15:33
Thanks, John. Learned a lot from your explanation.
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