Oiii LiviiiK Resources — Aqmitic Ecosystems 



241 



tumors than pelagic fishes (\.l'^/c and 1.0%, 

 respectively) even when collected from a rela- 

 tively unpolluted Canadian watershed. Both 

 groups of fishes, though, had higher rates of 

 tumors in the polluted Fox River of northeastern 

 Illinois (benthic fishes. 1 .Q'^7c: pelagic fishes, 

 3.0%) than in the Canadian system (Brown et 

 al. 1973). Hughes and Gammon (1987) noted 

 that increasing pollution seems correlated with 

 an increase in the incidence of abnormalities on 

 fishes of the Willamette River in Oregon. 

 Likewise. Tyler and Everett ( 1 993 ) reported that 

 bottom-dwelling barbel (Barbiis barhus) col- 

 lected from polluted rivers in England had a 

 higher incidence of abnormalities than those 

 collected from a clean river. Therefore, the rela- 

 tionship between a high incidence of abnormal- 

 ities on fish and polluted waters has been well 

 established. On the upper Illinois River, there 

 was a marginal trend of decreasing incidence of 

 abnormalities against years for pelagic fishes 

 since the early l960's (D = 3,156: P < 0.05). 

 coincident with known improvements in water 

 quality over the same period (Butts 1987), but 

 not for benthic fishes ^D = 1,937: P = 0.23). 



Conclusions 



Emerald shiner 

 (27.1%) 



Carp (287%) 



Goldfish (32 0%) 



Smallmoulh buffalo (0.6%) 

 Spottail shiner (1.3%) 

 Channel catfish (21%) 

 Bullhead minnow (6.0%) 



Sand shiner (10.5%) 



Blunlnose minnow (14 9%) 



Cenlrarchids (20 9%) 



• Green sunlish (10 4%) 



• Bluegili (4 6%) 



• Largemoulh bass (3 0%) 



• Smallmouth bass (2.9%) 



Other (4,6%) 

 Gizzard shad (9 3%) 



Emerald shiner (24 4%) 



Carp (5,3%) 



Fig. 3. Composition of catches 

 (%) for tlie upper Illinois Waterway 

 for 196.^ and 1992. based on num- 

 ber of individuals collected per 

 hour of electrofishina. 



1963 1992 



Long-term trends of fish populations in the 

 upper Illinois River reflect improved water 

 quality in recent years as compared with the 

 early 1960's. This trend is consistent with data 

 presented in other studies that showed improved 

 water quality in the upper Illinois River (Butts 

 1987; Lerczak et al. 1992). The increased inci- 

 dence of external abnormalities between bot- 

 tom-foraging fishes compared with pelagic fish- 

 es suggests contaminated sediments (Essig 

 1991: lEPA 1992). 



Because recovery of fish populations in the 

 upper Illinois Waterway appears to be a 

 response to pollution-control efforts, definite 

 restoration goals should be identified to help 

 guide further recovery and to determine expec- 

 tations. In addition, the specific causes for the 

 high incidence of abnormalities in benthic fish- 

 es need to be explicitly identified. 



References 



Brown, E.R., J.J. Hazdra. L. Keith, I. Greenspan, and J.B.G. 

 Kwapinski. 197.^, Frequency of fish tumors found in a 

 polluted watershed as compared to nonpolluted Canadian 

 waters. Cancer Res. .VV 189- 1 97. 



Butts, T.A. 1987. Illinois River water quality. Past, present, 

 future. Pages 195-209 in H. Korab. ed. Proceedings 

 Governor's Conference on the Management of the 

 Illinois River System: the 1990's and Beyond. Special 



Rep, 16, Water Resources Center. University of Illinois, 

 Urbana. 



Essig. H.W, 1991. Chemical and biological monitoring of 

 the upper Illinois River. Pages 68-77 in H. Korab, ed. 

 Proceedings 1991 Governor's Conference on the 

 Management of the Illinois River System; the 1990's and 

 Beyond. Special Rep. 19. Water Resources Center. 

 University of Illinois, Urbana, 



Hughes. R.M.. and J.R. Gammon. 1987. Longitudmal 

 changes in fish assemblages and water quality in the 

 Willamette River, Oregon. Transactions of the American 

 Fisheries Society 1 16:196-209. 



lEPA, 1992. Illinois water quality report. 1990-1991. 

 Illinois Environmental Protection Agency. Springfield. 

 4().s pp. 



Karr. J.R., K.D. Fausch. PL. Angenneier. PR. Yant. and l.J. 

 Schlosser 1986. Assessing biological integrity in run- 

 ning waters: a method and its rafionale. Illinois Natural 

 History Survey Special Publ. 5. 28 pp. 



Lerczak, T.V., R E. Sparks, and K.D. Blodgetl. 1992, The 

 long-term Illinois River fish population monitoring pro- 

 gram. Annual report to the Illinois Department of 

 Conservation (F-lOl-R-3). Aquatic Ecology Tech. Rep. 

 92/9. Illinois Natural History Survey. Champaign. .^1 pp. 



Mills. H.B., W.C. Starrett, and F.C. Bellrose. 1966. Man's 

 effect on the fish and w ildlife of the Illinois River. Illinois 

 Natural History Survey Biological Notes 57. 23 pp. 



Thompson. D.H, 1928, The "knothead" carp of the Illinois 

 River Illinois Natural History Survey Bull. 17(8):285- 

 .320, 



Tyler. C.R.. and S. Everett. 1993. Incidences of gross mor- 

 phological disorders in barbel iBarbus barbus) in three 

 rivers in England. Journal of Fish Biology 43:739-748. 



For further information: 



Thomas V. Lerczak 



Illinois Natural History Survey 



River Research Laboratory 



PO Bo.\ 590 



Havana, IL 62644 



