A fully grown Black Caiman is a big reptile, it is know to challenge even the mighty Green Anaconda another apex predator of the Amazon basin and swamp.
The Largest scientifically measured Black Caimans are said to be 17 feet or more and males this size weighed over 1,100 pounds perhaps 1,500 pounds but weights are rarely reported or documented.
The skull alone of a very large specimen weighs several pounds. The head alone is nearly 10 percent of body mass. The huge tail accounts for nearly 40 percent of total body mass.