This bird has me stumped. I have checked Sibley's and the BNA (Birds of North America) site and I can't find a match. I feel like it's a juvenile but juvenile what?
I shot this on Saturday at Aransas NWR near Winnie, TX (southeast TX)
I believe you're correct. The long neck threw me off. Most of the time their neck is pulled in. All of the online images that I've seen were like that.