Neotropic Cormorant

In Villahermosa, Mexico, while at La Venta on the Laguna de las Ilusiones, I photographed several cormorants and I've struggled to determine whether they are neotropic cormorants, double crested cormorants, or one or more of both. 

I'm pretty sure this is a neotropic cormorant as it has the white edge to the throat patch. 

As far as range is concerned, neotropic cormorants have a much greater range in Mexico than double crested cormorants, but they are both found in Villahermosa and can be found roosting together. 

Range of the neotropic cormorant (from Wikipedia).

Range of the double crested cormorant (from Wikipedia). 

The neotropic is smaller and more slender than the double crested, frequently holds its neck in an "s" shape, and has mainly black plumage with a yellow/brown throat patch. During breeding a white edge develops on the throat patch. Juveniles are brownish in color. 

I'm less certain on this one. It does have an "s" shaped neck and is about the same size as the one above (I saw them near each other). The significant brown may indicate it is still a juvenile.