I dunno...you may be right, but The side profile birds just do not fit for me. Also Dowitchers can sport an eye stripe at different stages and the extent of barring can vary as well.
Hmm.... tough one. My thoughts are the 2 inner birds look like Dowitchers.... look very chunky. The birds on both outer sides look smaller/thinner and look good for Stilts... but the left most bird I can see as a Dowitcher too.
Maybe Eastern Towhee for #1?... can't be 100% sure though. Both are Wood Ducks... the first is a male(the white cheek bridle can be seen), can't tell on the second. Agree with Red-tailed Hawk and Common Raven, as well as male Mallards on the additional pic.
In addition to Akandula's comments... the thickness of the bill and overall general size of this Royal Tern. As many IDs... the more field marks you can see or eliminate will point you to the correct ID.
Yes 2nd year bird. A first year bird at this time of year will look like the female. Some of this years male will have a few black specs in the fall(mostly on face) and the yellowish parts will be more orange(but this is certainly always not easy to tell in the field). The following spring(second year bird) will show much more black speckling(including on chest)... like this bird and many will be almost fully in adult male plumage by the second fall.... but some will wait until year 3 to show off their full beauty.