Burbot Lota lota has many desirable qualities as a study organism and as an indicator species for the quality of freshwater systems in northern latitudes (Stapanian et al., 2010). It is the only truly freshwater member of the cod family (Gadidae) and one of only two species of freshwater fish that have a circumpolar range (McPhail & Lindsey, 1970; McPhail & Paragamian, 2000). Burbot occupy the widest range of depths of all fishes found in the Laurentian Great Lakes basin (e.g., small streams to at least 300 m in Lake Superior) (Boyer et al., 1989). Burbot are among the few freshwater fishes known to communicate via vocalizations (Cott, 2013; Cott et al., 2013). Burbot are sensitive to anthropogenic disturbances, particularly dams and increased water temperatures (reviewed by Stapanian et al., 2010). However, nearly extirpated Burbot populations have recovered in some systems without stocking, following improved water quality and decreased predation from invasive species (Stapanian & Madenjian, 2007; Stapanian et al., 2006, 2008, 2010). Although external sexual dimorphism is subtle and seasonal, the testes of Burbot are very large compared with most other fishes (Cott et al., 2013) and Burbot exhibit sexual differences in range (Stapanian et al., 2013a) and uptake of contaminants (Madenjian et al., 2013, 2014; Stapanian et al., 2013b). Burbot have been shown to be ideal organisms for studies of contaminants in freshwater systems, revealing, for example that latitudinal trends in polychlorinated biphenyl congener distributions are more complex than previously thought (Stapanian et al., 2014), and like in “higher” vertebrates, androgen levels may enhance mercury elimination in teleost fish (Madenjian et al., 2015).

World-wide, many Burbot populations are threatened, endangered, or have been extirpated (reviewed by Stapanian et al., 2010). Although illegally stocked Burbot have spread in the upper Colorado River system (USA) (Gardunio et al., 2011), the species is often ignored in fish management and conservation programs (McPhail & Paragamian, 2000; Stapanian et al., 2010). This is due in part to its unpopularity as a sport and commercial fish in much of its range, despite studies indicating that Burbot meat is palatable and nutritious (Brannion, 1930; Tack et al., 1947; Staba, 1979; Addis, 1990; Stapanian & Kakuda, 2008 and references therein). Burbot ecology is poorly studied compared with that of most freshwater predators in North America and Western Europe (McPhail & Paragamian, 2000). Burbot larvae are difficult to culture for a variety of reasons, including a delicate body structure, small size at hatch, and live feed requirement for at least 5 weeks following alimentary tract development. These difficulties sometimes hamper restoring imperiled populations in some systems (e.g., Hardy & Paragamian, 2013).

In this special section of Hydrobiologia, we have assembled seven papers on diverse topics in Burbot ecology, culture, and management. They include a subset of the presentations given at the Fifth International Burbot Symposium, held during the International Congress on the Biology of Fish in Edinburgh, Scotland on 04 August 2014. Our primary objectives are to improve our understanding of Burbot and better management practices for this key species.