Unlike shallow-water fish inhabiting the Great Lakes, the bloater is well adapted to reaching great depths (6). This is due to its high bodily fat content, which aids buoyancy, as well as its ability to metabolise food at low temperatures (5).
During the day, the fish can be found near or on the bottom of the lake, but at night, some of the bloater population move upwards in the water column to feed (6). The bloater is considered to be an opportunistic feeder, mostly feeding on small aquatic invertebrates (5).
Being able to descend to such great depths allows the bloater to feed on zooplankton near the lake bottom, which other species are unable to reach. Because of this, the bloater is considered to be an integral part of food webs in the Great Lakes (5).
The fish spawns between September and March in various lakes and spawning grounds. A female bloater can produce up to 10,000 small yellow eggs, which may represent 30 percent of the female’s body weight when it begins to spawn (3). The bloater may live to around nine years of age, with the female generally living longer than males (7).