Greetings and Welcome.
What were the colors of the bird? Orioles are birds a little smaller than a robin. The males and females are colored differently, so you should have noticed the difference. Being in CA, it could be a escaped cage bird also. What size was the bird in comparison to some other common bird. such as Robin, Wren, etc?
You said that the nest was woven into the underside of a banana leaf. Was it attached to the underside or were two leaves woven together to create a "pouch"?
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