Overview:
Trout are carnivorous freshwater fish belonging to the genera Oncorhynchus, Salmo, and Salvelinus in the Salmoninae subfamily of Salmonidae. Some species, like the spotted seatrout, resemble trout but are not salmonids. They are related to salmon and display similar migratory behaviors, with most being potamodromous (living and spawning in freshwater). Anadromous species, such as steelhead and sea trout, spend part of their lives at sea. Brook trout and some others are char, closely related to trout and salmon.

Ecological Role:
Trout are mid-level predators feeding on smaller aquatic organisms and serve as prey for various wildlife. Their remains also provide nutrients for ecosystems, marking them as keystone species.

Species:
The name "trout" encompasses numerous species from the genera Salmo (e.g., brown trout), Oncorhynchus (e.g., rainbow trout), and Salvelinus (e.g., brook trout). Hybrids like tiger trout and splake exist, alongside similar fish from other families like the spotted seatrout.

Anatomy and Habitat:
Trout vary in color and markings depending on their environment, which helps with camouflage. They inhabit cold, clear water and have adaptations like an adipose fin and a physostome swim bladder. Introduced species have altered ecosystems in regions like Australia and New Zealand.

Diet:
Trout consume aquatic invertebrates, smaller fish, and, occasionally, land animals. Their diet influences their flavor, making crustacean-fed trout more flavorful.

Fishing and Food:
Trout are prized game fish caught through methods like fly fishing. They are also farmed for food, with their meat prepared similarly to salmon. The flesh's taste and texture depend on the fish's diet.

Conservation Concerns:
Native trout populations face threats from invasive species, hybridization, climate change, and habitat loss. Efforts like stocking sterile fish aim to mitigate genetic contamination and support recreational fishing.

Cultural and Recreational Significance:
Trout are celebrated in angling and culinary traditions, with their diverse species offering opportunities for both sport and sustenance.