The Striated Heron is found worldwide, except in North America, where the Green Heron takes its place. Actually in Panama both are possible and immatures are very similar. Based on this article, I am thinking Green Heron, but opinions welcome and hybrids possible. And later looking at an immature Striated Heron from Brazil, I am still totally unsure.
Anguilla,Antigua and Barbuda,Bahamas,Barbados,Belize,Bermuda,British Virgin Islands,Canada,Cayman Islands,Colombia, Costa Rica,Cuba,Dominica,Dominican Republic,Ecuador - Galapagos Islands,Ecuador - mainland,El Salvador,Grenada,Guatemala,Guyana, Haiti,Honduras,Jamaica,Mexico,Montserrat,Netherlands Antilles,Nicaragua,Panama,Portugal,Puerto Rico, Saint Lucia,Saint Vincent and the Grenadines,Suriname,Trinidad and Tobago,Turks and Caicos Islands,United States - mainland,Venezuela,Virgin Islands,
IOC 9.1 Subspecies
w USA, n Baja California (Mexico)
s Baja California (Mexico)
c and e USA and e Canada to Panama and the Caribbean