Balaenoptera physalus, commonly known as the fin whale, is the second-largest whale species, reaching lengths of up to 85 feet. Known for its streamlined body and distinctive asymmetrical coloration, it inhabits deep, offshore waters worldwide. Fin whales are fast swimmers and are often called 'greyhounds of the sea.' They play a vital role in marine ecosystems as filter feeders, primarily consuming krill and small fish.

The Balaenoptera physalus, commonly known as the fin whale, is found in oceans worldwide. Its distribution includes the North Atlantic and the North Pacific, as well as the Southern Hemisphere's oceans, covering the Arctic to the Antarctic. Specific regions where they are commonly observed include the Gulf of California, Mediterranean Sea, and the waters around Iceland, Newfoundland, and Greenland.

Fin whales prefer deep offshore waters and are commonly found in temperate and polar regions, though they occasionally venture into tropical waters. They inhabit both open ocean and coastal areas, often seen near continental shelves where upwelling currents bring nutrients to the surface.

Fin whales play a crucial role as apex predators in marine ecosystems. They primarily feed on small schooling fish, krill, and other crustaceans by filter-feeding through baleen plates. Their presence indicates healthy marine ecosystems as they require rich feeding grounds to sustain their large size.