A minnow is typically a freshwater fish and one of the largest classes of fish in the world with over 290 species. Most notably this species contains the carp family, including goldfish, and small fish that are commonly used as bait fish. They are generally small in size, although a select few species are incredibly large. Most species are plant-eating with an average lifespan of three years.
While a minnow is usually classified as a freshwater fish, certain species are considered a saltwater variety. This variation in habitat is what makes the minnow species one of the largest in the world. While most consider these types of fish as bait, they are also commonly found in home aquariums or decorative ponds. Many types of carp, also part of the minnow family, part of the cuisine throughout Europe and Asia.
Minnows are usually small, averaging 6 inches (15 cm) in length. More rare species, such as the Colorado Pikeminnow, can reach up to 6 feet (1.8 meters) in length and weigh nearly 100 pounds (45 kilograms). These larger types of fish can live for up to 50 years, well outside the average three years for smaller minnows.
The vast majority of minnows live in large schools and spawn between early spring and summer. The male minnow will usually change colors, typically red or orange, to attract a mate. Females can lay up to two million eggs, which accounts for the massive schools of minnows found in larger bodies of water. The manner in which eggs are laid varies by species. Male minnows generally build a nest of rocks for the female to lay the eggs. In some cases, a minnow will dig a hole in the bottom of the body of water for the eggs.
In the hierarchy of the different fish species, most minnows are at the bottom. They typically eat plants, most commonly algae, and then convert the plant product into protein. In turn, they become the food source for many medium sized and larger fish, making them one of the perfect baits for sport fishing. A larger minnow, however, will often eat insects and even other, smaller, minnows.
Different species of these fish can be found all over the world, from Japanese carp ponds to a goldfish tank in the local pet shop. Bait shops usually carry flat head minnows and gold shiners for avid anglers, and European and Asian restaurants often have carp on the menu. The adaptability to different habitats and the large amount of eggs that the minnow can lay at one time makes it, arguably, the largest and most stable type of fish in the world.