Burbot population dynamics in northern Lake Michigan, 2001–2023, and predation on newly stocked lake trout by burbot

Although the worldwide status of burbot (Lota lota) across its Holarctic distribution has recently been assessed, adverse effects of dreissenid mussels on burbot abundance in waters invaded by mussels have not been investigated. We analyzed data from an annual spring gillnet survey to characterize burbot population dynamics in northern Lake Michigan during 2001–2023. Adult burbot abundance in northern Lake Michigan trended neither significantly upward nor downward during 2001–2023. Thus, expansion of the quagga mussel (Dreissena rostriformis bugensis) population into deeper waters of Lake Michigan during 2003–2008 had no detectable negative effects on burbot abundance. Burbot continued to feed on lake trout (Salvelinus namaycush) stocked in the Northern Refuge of Lake Michigan through 2023, which supported a hypothesis that the burbot population potentially impeded lake trout restoration in the refuge.