Bird Disappearance Mystery At Seahorse Key, Florida

My guess after raising parrots for 20+ years would be: the snake population has crossed the tipping point. If it was a temporary anomaly, they would return in a few dyas/weeks. Being gone this long leads me to believe that the cause of their departure is still there.
Birds will fight before abandoning their nests, and what ever the threat is, they have determined to be too great to remain there.

It would be interesting to know if the boas and pythons have reached Seahorse Key. The cotton mouth population is horrendous, and that alone could be the cause.

P.S. A couple of other possibalities occur to me: birds are ultra-sensitive to earth changes, and will start acting strangely for days- sometimes weeks - before even our most sensitive instruments pick up anything. I doubt it would be earthquake related, but a methane leak would not be surprising, Don't know if there are any volcanoes close enough for birds to percieve as a threat, or even a new one forming in the ocean? 

Earth related, or predator related? Will be interesting to see what unfolds. Native Americans aleays watched the animals closely for signs, and if they detected a mass exodus, they would follow the animals. I don't think I'd like to visit Seahorse Key right now.