IN THE BEGINNING (TO 1850) 



Fish Communities 



The fish-species complex in the Great Lakes has changed drastically. 

 Unlike many large lakes of the world, especially the large African lakes 

 and Lake Baikal (USSR), the Laurentian Great Lakes have had only 10 thou- 

 sand years between the retreat of the glaciers and the coming of man to 

 produce, through evolutionary forces, a complex of species that is unique 

 to the system. 



The Great Lakes system did produce a few unique species in this short 

 period, indicating that the processes were well underway to further species 

 diversity. The evidence for this conclusion is best illustrated by the 

 five endemic species (Smith, 1957; Scott and Crossman, 1973), all of the 

 subfamily Coregoninae (whitefish) in the Samonidae (salmon family). These 

 five species listed in descending order of size were: 



deepwater cisco - Coregonus johannae 



longjaw cisco - Coregonus alpenae 



shortnose cisco - Coregonus reighardi 



kiyi - Coregonus kiyi 



bloater - Coregonus hoyi 



According to Scott and Crossman (1973) all five species were found in Lakes 

 Huron and Michigan, four in Lake Superior, three in Lake Ontario, and one 

 in Lake Erie. 



In addition to the five endemic species of ciscos, these wider ranging 

 species were also present: lake herring ( Coregonus artedii ); blackfin 

 cisco ( Coregonus nigripinnus ); and shortjaw cisco ( Coregonus zenithicus ). 

 These eight species of ciscos, together with the lake whitefish ( Coregonus 

 clupeaformis ) and round whitefish ( Coregonus cylindraceum ), characterized 

 the Great Lakes fish community. Most of the species of the whitefish sub- 

 family, especially the ciscos, were inhabitants of deep, cold water and 

 therefore reached their greatest diversity in Lakes Superior, Huron, 

 Michigan, and Ontario (Table 1). The dramatic alteration in the species 

 complex of deepwater ciscos that subsequently occurred was documented by 

 Smith (1964) for Lake Michigan. 



In addition to the Coregonines other groups and species were abundant 

 in the lakes. The dominant predators of the open waters present in all five 

 lakes were the lake trout ( Salvelinus namaycush ) and burbot ( Lota lota ) . In 

 the bays and nearshore areas were: lake sturgeon ( Acipenser fulvescens ); 

 northern pike ( Esox lucius ); suckers (primarily Catastomus catastomus and 

 C. commersoni ); channel catfish ( Ictalurus punctatus ); bullheads ( Ictalurus 

 spp.); white bass Morone chrysops ; freshwater drum ( Aplodinotus grunniens ); 

 and three species of the perch family: yellow perch ( Perca flavescens ); 

 walleye ( Stizostedion vitreum ); and sauger ( Stizostedion canadense ). All 

 of these species have been historically of commercial significance. The 

 Atlanta salmon ( Salmo salar ) and American eel ( Anguilla rostrata ) were also 

 abundant and became commercially important only in Lake Ontario. 



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