Zeb Hogan, biologist, explorer, and photographer, is on a mission to document and protect the world’s freshwater fish. Hogan knows that unprecedented usage of freshwater around the world has led to declining populations of many aquatic species. He and the MegaFishes Project plan to help.

The world’s largest freshwater fish, many weighing more than 200 pounds, face the biggest threat. Working with a network of more than 100 scientists, fishermen, and local populations in 17 countries, Hogan examines the causes of (and potential solutions to) the global loss of freshwater biodiversity. They hope their work will lead to another first: identifying the planet’s largest freshwater fish.

As the star of Nat Geo WILD’s Monster Fish, Hogan guides viewers on a global