Which fish species have been important in the Great Lakes?

The fish community of the Great Lakes has undergone significant changes over the past century, shaped by both native species and the introduction of nonindigenous ones.1

Historically Important Species

Native species that have long been significant to the lakes include:
* Lake trout: Once a major commercial species, populations collapsed in the mid-20th century due to the invasive sea lamprey but were later reintroduced.12
* Whitefish: Historically important, though their range was restricted by pollution and damming of tributaries.1
* Salmon and Lake herring: Long-standing components of the lakes' fish population.1
* Shallow-water species: Perch, walleye, bass, and catfish remain abundant in warmer, shallow waters.1

Introduced and Invasive Species

The ecosystem has been heavily impacted by nonindigenous species:
* Alewife: After migrating into the upper lakes, they became the most abundant species by the mid-20th century, eventually requiring the introduction of coho and chinook salmon to control their population.13
* Sea lamprey: A predatory invasive species that caused the collapse of native predator populations.1
* Other species: The round goby and ruffe compete with native fish, while Asian carp species are considered a significant threat to the ecological balance.14