Is a rainbow trout an autotroph or a heterotroph?

Autrotrophs are mostly plants who can make their own food from sunlight in a process called photosynthesis. While a heterotroph creature cannot make its own food and most depend on other organisms for food, which is by eating them. I am pretty sure that a herrinbg gull is a heterotroph, since it obviously cannot get it s food from the sun. Hope this helps.