I'm going to pull up the Mourning warbler photos and data and give it a really good look - and compare it to the Connecticut. But I've never heard of the Nashvilles down here - and from what I hear, they are much smaller than the Connecticut. This one was foraging around on the ground, and the head, neck, and throat right to the breast were all one continuous grey hood - and a fairly distinguished white eye ring, with a yellow chest that extended all the way to the underside of the tail. It looked a bit large for a typical warbler - when I first spotted it, I saw only the head and eyering, and a bit of the yellow chest - I was thinking something between a white eyed vireo or a painted bunting female - when it finally became more clear, the grey hood was obvious, as well as the olive back and wings. I followed it around with my lens, but so many branches were between me and it that I had to switch to manual focus, cranked up to ISO3200 it was still dark, and I never could get it to come out in the open. I finally lost it when it moved too far back in the tree canopy - that section is boardwalk, so I couldn't pursue.
Thanks for the hummingbird ID - I suspected it might be a ruby-throated - as I've heard that their red throat can be sometimes unnoticeable, and can even look black when the light doesn't hit it from the right angle...but I know so little about them and tried looking up a few in the bird pages. It's my first hummingbird photo, and only one of a handful of times I've spotted one down in South Florida. Obviously that's not a 'keeper' photo - that's mega-cropped and artificially brightened about 2 stops in post to try to help ID it.
