I took this picture in the Florida Keys at a bird sanctuary which explains a lot since Masked Booby's are rarely seen in the U.S. aside from being a visitor to the Florida Dry Tortugas where it's a known visitor for many years. The Masked Booby began nesting there in the 1980s small sandy islands barely above high-water level with little or no vegetation.
It's difficult to determine the total population because colonies are numerous and widely scattered which probably also ensure its survival. They live in tropical seas foraging over warm water sometimes hundreds of miles from any land. Widespread in tropical oceans, the long-winged Masked Booby occurs regularly off the southern Atlantic and Gulf coasts and is common in Hawaii's northwestern chain.