Giant fish are large species of fish that can be found in various aquatic environments, including oceans, rivers, and lakes. Some well-known examples include the whale shark, which is the largest fish in the world, and the sturgeon, known for its size and roe. These fish can grow to impressive lengths, with some reaching over 40 feet. Many giant fish play important roles in their ecosystems. They often serve as apex predators or help maintain the balance of their habitats. Conservation efforts are crucial for protecting these species, as many face threats from overfishing and habitat loss.