and four hybrids have been documented by project F-101-R sampling (1989- 

 present); 44 species and three hybrids from eleven families were collected during 

 26.00 h of sampling in 1998. One species, the freckled madtom (a single specimen), 

 was collected for the first time during project F-101-R sampling along the waterway; it 

 was taken at Sugar Creek Island on La Grange Reach (middle river) in 1997. Also 

 not collected previously was a green sunfish x orangespotted sunfish hybrid, found at 

 the Lower Twin Sister site (RM 202.8) in 1997. We continue to document the 

 relatively low abundance of common carp in Starved Rock Reach; this species has 

 ranked extremely low in terms of catch rate in numbers in Marseilles and Dresden 

 Reaches for several years. Goldfish, which were abundant in our samples in 1989 

 (82 individuals were collected) occurred only infrequently at sites in 1997 and 1998 

 (5 individuals were collected each year). Small minnow species, such as bluntnose 

 minnow, bullhead minnow, emerald shiner, and red shiner, were extremely low in 

 abundance in the upper watenway in 1996. However, sampling in 1997 and 1998 

 indicates these species are once again numerous in these reaches. 



We noticed a high degree of variability in species richness among sites and 

 also among river reaches. Some of this variability can be explained by sampling 

 duration (site comparisons) or the number of sites sampled (reach comparisons), but 

 there is also evidence some of our sites are inherently lower in species richness than 

 others. For example, at most sites we have collected an average of 14-16 species 

 during the ten years of project F-101-R sampling. However, at Hennipin (RM 207.6), 



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