Fish are vertebrates living in water with hard bones and gills. They are cold-blooded animals that lay eggs. Fish differ from reptiles and amphibians in being aquatic and lacking hair
Freshwater fish live in bodies of water with salinity below 1.05%. 41.24% of all fish species live in freshwater environments. Fish need special adaptations for survival in fresh water. Many species are anadromous (reproduce in freshwater, live in sea). Some are catadromous (born in salt water, live in freshwater)
Albacore reaches up to 1.4 m in length with deep blue dorsal and silvery white ventral color. Has long pectoral fins extending up to 30% of total length. Forms schools with other tuna species and migrates between different regions
Rainbow trout (Oncorhynchus mykiss) is native to Pacific tributaries. Freshwater forms reach 0.5-2.5 kg, lake forms up to 9 kg. Distinguished by broad reddish lateral line stripe, especially in breeding males. Maximum lifespan is 11 years
Trout are carnivorous freshwater fish belonging to three genera. Most trout are potamodromous, spending life in freshwater and migrating upstream. Some species, like steelhead and sea trout, are anadromous. Trout are classified as oily fish and important food source
Whale shark (Rhincodon typus) is the largest living non-cetacean cartilaginous fish. Average adult whale shark measures 9.7 m long and weighs 9 tonnes. Largest verified whale shark specimen was 12.7 m long and 21.5 tonnes