In the depths of Lake Champlain, an eel-like creature slithers among the rocks, hunting for a foraged fish dinner. This is no sinister cousin of Champ—this is the burbot (Lota lota), one of Lake Champlain’s only deep-water predator fish (the other one is lake trout). Burbot have a unique look, with small scales forming patterns of blotched green, brown, yellow, and black, all making up their particularly slimy skin. Perhaps their most distinct feature is the single “barbell” protruding from under their chin—think of a long, narrow goatee made of scales rather than hair. They also have large, wide-set, tubular nostrils that protrude from the front of their face, resembling catfish.
Catfish-like not only in their facial features, burbot are also bottom-dwellers throughout most of the year. They’re well suited for the depths, with their dark coloring for camouflage, bulging nostrils for sensing beyond sight, and long, flexible bodies that enable them to burrow in a wide variety of substrates. Burbot burrow during the day and are crepuscular hunters, meaning they hunt near dusk and dawn. The fish are voracious predators and are not fussy about their food. They primarily feed on other fish, including smelt, yellow perch, lake trout, sticklebacks, and bass. They also eat fish eggs, clams, crayfish and other crustaceans, and feed on insects and other macroinvertebrates before the adult stage. This broad diet can benefit them as they eat whatever may be around, but it also works to their detriment as it makes them easier to trick with lures.
Burbot have a unique spawning strategy. While most other fish are taking a winter’s rest, burbot emerge from their usual deep, dark home to gather in shallow, rocky, and sandy shoals—from ten feet to as shallow as two feet deep. They meet in pairs or sometimes in large, tangled balls of several—even dozens—of individuals. The spawning period occurs between December and March, in chilly temperatures from 33 to 39 degrees Fahrenheit. Burbot fall under a category of fish known as “broadcast spawners,” meaning that instead of preparing a place to spawn and nest fertilized eggs, they shoot their eggs and sperm into open water and thrash about to mix them together. These eggs then drift to the bottom and--if successfully fertilized--develop for about a month in the cold shallows. They hatch at the tiny size of three to three and a half millimeters (less than 0.15 inches), making them one of the smallest of freshwater fish larvae in the lake.
Burbot are difficult to study due to their nature as cold-water fish who spend most of their time in the lake’s depths: when they visit shallower areas, it is under ice. New research techniques using radio telemetry are being developed to demystify this creature and other fish who are active in the cold. Read more about fish in winter in this LCC E-News article and keep a look out for spawning burbot—maybe even a ball of them! —in your local, shallow icy shoal.