Watch this Florida man’s insane reaction as he gets the surprise of his life when he sees a 552 lb monster at the side of his kayak.

What do you do when you see a leviathan-sized, Goliath Grouper swim up from the depths to the side of your tiny little kayak? Apparently, you scream like a little girl! Dazed and confused, and still shrieking with excitement, angler Jon Black hangs on for dear life to his rod (which later snaps!) while the grouper splashes him relentlessly with his monstrous tail in a display of power and agility.

Grouper are known for their stout body and wide mouth. They swallow prey hole using a strong suction, pulling prey into their huge mouths, rather than taking bites out of prey. Goliath Grouper can reach sizes up to 800lbs and their lifespan is between 30 and 50 years.

Another interesting fact about grouper is that they are transgender! They have the ability to transform themselves from female into male. This happens when they reach a certain age. What is the benefit of this kind of life cycle? Some researchers suggest that a possible benefit is that the energy-consuming process of growing eggs is better left to younger, healthier fish. In this way, the genetic pool is kept strong and produces healthier and stronger populations overall.