Today's image features a black caiman, South America's stealthy river giant, in the Tambopata National Reserve, Peru. These caimans are the largest species in the alligator family, growing up to 6 metres and weighing more than 450 kilograms. What sets them apart is their dark green colour, which helps them blend into the murky depths. These carnivorous creatures thrive in freshwater environments such as slow-moving rivers, lakes and seasonally flooded savannahs. From these waters, they hunt for birds, fish, turtles and occasionally big mammals. Black caimans play an important role in making sure ecosystems stay balanced by keeping their prey's populations under control. Fewer caimans mean more piranhas, which attack cattle, and more capybaras, which cause crop damage.