Occurred on October 22, 2018 / Cairns, Australia
Info from Licensor: "Captive American Alligators bellowing to communicate their size to each other. The frequency of the bellow indicates to all of the other alligators in the area the size of each other. This lessens the chance of there being an unnecessary confrontation between gators of vastly different sizes. They continue to bellow back and forwards to each other for a number of minutes, and the call can be heard over large distances."