DEEPWATER CISCO Coregonus johannae (Wagner, 1910) 



Order: SALMONIFORMES Family: SALMONIDAE 



Significance : The deepwater cisco is one of the two most important species in the early 

 chub fishery of the Great Lakes . 



Distinguishing characteristics : Second largest of the ciscoes of the Great Lakes 

 distinguished by its very pale coloration and fewer gill rakers than other ciscoes . 



Present distribution : Unknown if extant . 



Former distribution : Once abundant in deeper waters of Lakes Michigan and Huron. 



Status : At least seriously depleted, although probably extinct. 



Estimated numbers : Last specimen reported in Lake Michigan in 1951 . None seen 

 subsequently in fishery surveys of Lakes Michigan and Huron. 



Fecundity : Spawned in deeper waters in late summer. 



Reasons for decline : The decline in the early 1900 's was probably due to intensive 

 commercial fishery . Recent decline and disappearance due to sea lamprey predation and 

 continued heavy fishing for larger ciscoes during the 1940's and 1950's. 



Protective measures already taken : None . 



Measures proposed : If a relict stock is found, they might be transferred to a remote lake. 



Number in captivity : None . 



Culture potential in captivity : Unknown . 



Remarks: Data submitted by Dr. Stanford H. Smith, Bureau of Commercial Fisheries, 

 Ann Arbor, Michigan. Dr. Stanford Smith, BCF, in his letter of July 31, 1967, said, 

 "The last record of a deepwater cisco was in 1951." Dr. R. R. Miller reported on 

 October 3, 1968, that the deepwater cisco is extinct. 



References : 



Hile, R. and H.J. Buettner . 1955. Commercial fishery for chubs (ciscoes) in 



Lake Michigan through 1953. U.S. Fish and Wildlife Serv . , Spec. Sci. Rept.- 



Fish. (163)? 49. 

 Koelz, W. 1929. Coregonid fishes of the Great Lakes, Bull. U.S. Bur. Fish. 



43, 1927:297-643. 

 Smith, S. H. 1964. Status of the deepwater cisco population of Lake Michigan. 



Trans. Am. Fish. Soc . , 93(2): 155-163. 



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