Fish Species of the Ob River (Siberia)

The **Ob River**—Russia's longest (3,650 km / 5,410 km with Irtysh)—drains western Siberia into the Kara Sea (Arctic). Its cold, nutrient-rich waters host a distinctive fish assemblage:

Sturgeons (Acipenseridae) — The Giants

• Siberian Sturgeon (*Acipenser baerii*): Large, commercial caviar/meat.
• Sterlet (*Acipenser ruthenus*): Smaller, early maturing, prized caviar.

Salmonids (Salmonidae)

• Atlantic Salmon (*Salmo salar*): Anadromous; enters from Kara Sea to spawn (rare now).
• Taimen (*Hucho taimen*): **World's largest salmonid** (up to 100 kg / 2 m). Apex predator. "River wolf."

Whitefishes (Coregoninae) — The Abundant

• European Cisco / Peled (*Coregonus peled* / *C. albula*): Pelagic, planktivorous.
• Broad Whitefish (*Coregonus nasus*), Muksun (*C. muksun*), Nelma (*Stenodus nelma* — "Arctic Cisco" / "Sheefish"): High-value commercial/subsistence.

Other Key Species

• Northern Pike (*Esox lucius*): Ubiquitous predator.
• Burbot (*Lota lota*): Only freshwater cod; winter spawner under ice.
• Perch (*Perca fluviatilis*), Roach (*Rutilus rutilus*), Ide (*Leuciscus idus*): Widespread cyprinids/percids.
• Wels Catfish (*Silurus glanis*): Large, in lower reaches.

Threats

• Dams (Novosibirsk, etc.) block migrations.
• Pollution (industrial, agricultural).
• Overfishing / poaching (sturgeons).
• Climate change (warming, flow alteration).

The Ob is a cold-water, high-latitude fishery of global significance.