Burbot (Larval stage)
Lota lota
Type: freshwater
Physical Characteristics
In this larval stage, the fish is nearly transparent with a prominent visible eye and a primitive yolk sac. As adults, they develop a long, eel-like body with two dorsal fins (the second is very long), a single chin barbel, and small, embedded scales that give a smooth, slimy feel.
Habitat & Distribution
Found across the Northern Hemisphere in cold freshwater lakes and large rivers. Larvae often inhabit shallow, near-shore areas shortly after hatching before moving to deeper, colder benthic habitats.
Size & Weight
Adults typically reach 40 to 80 cm and weigh 1 to 3 kg, but can grow up to 1.5 meters and exceed 12 kg.
Similar Looking Species
Eels (Anguilla) have a single continuous fin. Catfish have multiple barbels and no second dorsal fin. Atlantic Cod are similar but marine and lack the single chin barbel.
Ecological Role
As larvae, they are part of the zooplankton-feeding community; as adults, they are significant benthic apex predators that regulate populations of other fish and invertebrates.
Diet
Larvae feed on rotifers and copepods. Adults are opportunistic carnivores, eating fish, crayfish, and insects.
Behavior
Primarily nocturnal and solitary. They are most active during the winter months, even under ice, while becoming relatively sedentary in deep, cool waters during summer.
Reproduction
Unique among freshwater fish for spawning in mid-to-late winter under ice. They gather in 'spawning balls' and broadcast eggs over sand or gravel; the eggs are semi-buoyant and drift until hatching.
Conservation Status
Least Concern (IUCN), though some localized populations are threatened by habitat degradation and warming water temperatures.
Identification Tips
Look for the single chin barbel and the two dorsal fins (the second being very long). The larval stage is identified by its large eyes and distinct vertebral column visible through transparent flesh.
Interesting Facts
The Burbot is the only member of the cod family (Gadidae) that lives exclusively in freshwater. They are sometimes called 'lawyers' or 'eelpouts' due to their unique appearance.
Identified on: 5/20/2026
Mode: Standard