I L L I N I S UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN PRODUCTION NOTE University of Illinois at Urbana-Champaign Library Large-scale Digitization Project, 7.
ILLINOIS NT A TITD A I LIIC T'tRDY i- U JL IL V\JL J-- SURVEY THE LONG-TERM ILLINOIS RIVER FISH POPULATION MONITORING PROGRAM Project F--R-4 Annual Report to the Illinois Department of Natural Resources Michael A. McClelland and Mark A. Pegg Illinois Natural History Survey LTRMP Havana Field Station 74 North Schrader Avenue Havana, illinois 6644-55 March 3 Center for Aquatic Ecology Technical Report 3/5
The Long-Term Illinois River Fish Population Monitoring Program F--R-4 Annual Report Michael A. McClelland and Mark A. Pegg Illinois Natural History Survey Illinois River Biological Station 74 North Schrader Avenue Havana, Illinois 6644-55 March 3 Dr.M( A. Pegg, Principalr96estigator Center for Aquatic Ecology Illinois Natural History Survey M. A. McClelland, Co-Inv6stigator Center for Aquatic Ecology Illinois Natural History Survey "r. J.M. E if nio Director Center for Aquati Ecology iilinois Natural History Survey
DISCLAIMER The findings, conclusions, and views expressed herein are those of the researchers and should not be considered as the official position of the United States Fish and Wildlife Service or the Illinois Department of Natural Resources. ACKNOWLEDGMENT OF SUPPORT The Long-term Illinois River Fish Population Monitoring Program (F--R) is supported by the Federal Aid in Sport Fish Restoration Act ((P.L. 8-684, Dingell- Johnson/Wallop-Breaux).
EXECUTIVE SUMMARY Between 7 August and 3 September of, 7 sites on the Illinois River Waterway and one site on Reach 6 of the Mississippi River were electrofished to monitor fish communities. A total of 4,565 fish representing 5 species (plus hybrids) from families were collected during 7 hours of sampling. Collections made in indicated an abundance of bluegill and gizzard shad throughout the waterway and continued high numbers of emerald shiners and bullhead minnows, important forage fish, in the upper waterway. Common carp and goldfish, species which were once dominant, continue to remain relatively low in abundance throughout the Illinois River Waterway, contributing only 4.% and.4% of the total catch respectively. For the second time during project F--R sampling along the waterway, silver carp were collected from one site, Lower Bath Chute (RM 7., La Grange Reach). A northern hogsucker was again collected for the second time since project F--R began in the Marseilles Reach. The sample from Lambie's Boat Harbor (RM 7.3, Peoria Reach) yielded the most fish (95,.% of the total collected from all 8 sites). Species richness at sites ranged from at Lambie's Boat Harbor (RM 7.3, Peoria Reach) to 6 at Moore's Towhead (RM 75.3, Alton Reach). Species richness of the lower, middle, and upper waterway was 9, 4, and 9 respectively. In, cyprinid numbers continued to remain relatively high in the upper waterway, with emerald shiners being the most abundant making up 9.3% of the total catch. Emerald shiners were also the most abundant species in Marseilles Reach at 44.% and Starved Rock Reach at 8.%. Bullhead minnows were the second most abundant species for Dresden Reach, making up 5.5% of the total catch. Bluegill ranked second in relative abundance for the upper waterway (8.%) and first in Dresden Reach (6.6%). Important sportfish species such as black crappie, bluegill, largemouth bass, and channel catfish were collected in all six waterway reaches in. Bluegill catch per unit effort in number (CPUEN) ranged from 83.5 in Dresden Reach (upper waterway) to 7.48 in Alton Reach (lower waterway). Largemouth bass CPUEN ranged from 7. in Dresden Reach to.4 in La Grange Reach (middle waterway). Channel catfish CPUEN ranged from.35 in Alton Reach (lower waterway) to. in Marseilles Reach (upper waterway). Black crappie CPUEN ranged from 7. in Reach 6 (Mississippi River) to. in Marseilles Reach (upper waterway). In terms of pounds of fish collected per hour (CPUE w), common carp ranked first in La Grange, Peoria, and Marseilles Reaches and second in Alton, Starved Rock, and Dresden Reaches. Channel catfish ranked first and comprised 3.% of the total catch in weight for Alton Reach with a CPUEw of.6. Smallmouth buffalo ranked first and compromised 4.% of the total catch in weight for Starved Rock reach with a CPUEw of 5.77. Largemouth bass ranked first and compromised 3.8% of the total catch in weight for Dresden Reach with a CPUEw of 4.4. A total of fishes collected in had externally visible abnormalities, of which (83.3%) were sediment-contact fishes (e.g., common carp), with the remainder being water-column fishes (e.g., bluegill). The highest incidence occurred in the upper waterway, where.% of benthic fishes had abnormalities, while the middle had.3% and lower waterway had.7% of benthic fishes with abnormalities. This is an indication (as we have noted in previous years) that the water column of the upper waterway is much improved (following the Clean Water Act) while the sediments of these reaches may continue to contain stressful factors for fishes.
TABLE OF CONTENTS Title and Signature Page...a D IS C LA IM E R... a ACKNOWLEDGMENT OF SUPPORT... EXECUTIVE SUMMARY...a 3 TABLE OF CONTENTS... 4... LIST OF TABLES... 6 LIST OF FIGURES...7 INDEX TO JOB ACCOMPLISHMENTS... 8 ACKNOWLEDGMENTS...9 INTRODUCTION... STUDY AREA AND METHODS... DATA ANALYSIS... 3 RESULTS AND DISCUSSION... 4 A. CONDITIONS DURING ELECTROFISHING RUNS... 4 B. ELECTROFISHING RESULTS... 5 Numbers of Fish Collected...5 Catch Rates in Numbers of Individuals Collected per Hour by Reach... Alton (lower river)...... La Grange (middle river)... 6 Peoria (middle river)...7
Starved Rock (upper river)... 7 M arseilles (upper river)...8 Dresden (Des Plaines River)...9 Catch Rates in Weights (pounds) Collected per Hour by Reach...3 Alton (lower river)...3 La Grange (m iddle river)... 3 Peoria (m iddle river)...34 Starved Rock (upper river)... 34 Marseilles (upper river)... 35 Dresden (Des Plaines River)...35 Fish Health Determined by External Visual Inspection... 36 CONCLUSIO NS... 37 LITERATURE CITED... 39 APPENDIX A... 4 APPENDIX B... 43 APPENDIX C... 44
LIST OF TABLES Table. Station information and characteristics during sampling in......... Table. Numbers of individuals of each fish species collected on the Mississippi River (Brickhouse Slough) and the lower Illinois River (Alton Reach, RM -8) in... 6 Table 3. Numbers of individuals of each fish species collected on La Grange Reach (RM 8-58) of the middle Illinois River (R M 8-3) in... 7 Table 4. Numbers of individuals of each fish species collected on Peoria Reach (RM 58-3) of the middle Illinois River (R M 8-3) in... 8 Table 5. Numbers of individuals of each fish species collected on Starved Rock, Marseilles, and Dresden Reaches of the upper Illinois Waterway (RM 3-8) in... Table 6. Numbers of individuals of each fish species collected per hour of electrofishing on Reach 6 of the Mississippi River (Brickhouse Slough) and on six reaches of the Illinois River W aterw ay in... 3 Table 7. Species ranked by relative abundance in number of fish collected per hour for... 5 Table 8. Pounds of each fish species collected per hour of electrofishing on Reach 6 of the Mississippi River (Brickhouse Slough) and on six reaches of the Illinois River W aterw ay in......... 3 Table 9. Species ranked by relative abundance in pounds of fish collected per hour for... 33
LIST OF FIGURES Figure. Three segments of the Illinois River sampled by electrofishing to monitor fish communities in...
INDEX TO JOB ACCOMPLISHMENTS Job a Prepare electrofishing equipment and train staff...4 Job Sample by electrofishing at 8 sites along the Illinois River Waterway and Reach 6 of the Mississippi River...4 i Job 3 Update computer database... 4 Job 4 A nalyze data... 3 Job 5 Presentation of results...5 ajob numbers and titles refer to the F--R-4 annual work plan dated January
ACKNOWLEDGMENTS Project F--R is supported by the Federal Aid to Sportfish Restoration Act (P.L. 8-68, Dingell-Johnson/Wallop-Breaux), with funds administered by the U.S. Fish and Wildlife Service and the Illinois Department of Natural Resources (IDNR). Mr. Larry Dunham (IDNR), Mr. Bill Bertrand (IDNR), Mr. Michael Sweet (IDNR), Dr. David Thomas, Chief of the Illinois Natural History Survey (INHS), and Dr. John Epifanio, Director of the Center for Aquatic Ecology (INHS) provided administrative support. Ms. Cammy Smith of the Illinois River Biological Station at Havana provided secretarial support and data entry and verification. Mr. Thad Cook assisted with the field work. This survey was originally conceived and initiated in 957 by the late Dr. William C. Starrett.
INTRODUCTION This report presents a summary of data collected in during segment 4 of federal aid project F--R, The Long-term Illinois River Fish Population Monitoring Program. Previous summaries of the long-term data set, begun in 957, were given by Sparks and Starrett (975), Sparks (977), Sparks and Lerczak (993), Lerczak and Sparks (994), Lerczak et al. (994), and Koel and Sparks (999). The annual reports for project F--R will continue to build on previously collected data with major analyses of the long-term data set scheduled for the five-year project report at the end of segment 5. The format used in this report is patterned after previous annual reports of this project (Lerczak et al. 993, 994, 995, and 996; Koel et al. 997 and 998; Koel and Sparks, 999; Arnold et al. ; McClelland and Pegg,.) to allow for easy comparisons of data among years. STUDY AREA AND METHODS Twenty-seven sites at fixed locations were sampled for fish along the Illinois Waterway. Twenty-six of these site locations are defined by Sparks and Starrett (975) and Lerczak et al. (994). In 999, the twenty-seventh site was added at Moore's Towhead on the Alton Reach, Illinois River mile 75.3, to more closely monitor fish communities near the Nature Conservancy's (TNC) floodplain restoration project (Spunky Bottoms); (Table ). Twenty-five of the sites were along the Illinois River, with two additional sites on the lower Des Plaines River. The Des Plaines River, along with the Illinois River forms part of the Illinois Waterway. One additional site was on the Mississippi River (Figure ). Seventeen of the sites were in side channels; the
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v w Mississippi River Lake Michigan M Ri Peoria RM 58 'Middle Lower River St. Louis Metropolitan Area Mississippi River River! Iv Kankakee River rway River Mile 79.8 77.3 6.6 49.6 48. 4.5 4.8 5.3 7.6 3.3.8 93.8 8.6 7.3 63.3 55. 48. 3. 7. 95. 75.3 86.5 58.3 3. 6.8 4.7 9.. Site Name Treats Island Du Page River Waupecan Island Johnson Island Ballards Island Bulls Island Bend Bulls Island Clark Island Hennepin Upper Twin Sister Lower Twin Sister Henry Island Chillicothe Lambie's Boat Harbor Lower Peoria Lake Pekin Turkey Island Upper Bath Chute Lower Bath Chute Sugar Creek Island Moore's Towhead Grape-Bar Islands Big Blue Island Crater-Willow Islands Hurricane Island Dark Chute Mortland Island Brickhouse Slouqh ii Figure Three segments of the Illinois River Waterway sampled by electrofishing to monitor fish communities in.
remaining sites were in other habitats, including the main channel border, or in a combination of habitat types (see Lerczak et al. 994). Following water quality measurements (e.g., dissolved oxygen) at each site, fish populations were sampled by electrofishing from a 6-ft (5-m) aluminum boat using a 3-watt, three-phase AC generator. Sampling at each site typically lasted one hour. Stunned fish were gathered with a dip net (/4-in [.64-cm] mesh) and stored in an oxygenated livewell until sampling was completed. Fish were then identified to species, measured (total length and weight), inspected for externally visible abnormalities, and returned to the water. More details on the electrofishing method and equipment are given by Lerczak et al. (994). DATA ANALYSIS At each site, number of individual fish and total weight (pounds) were tallied for each species. Fish catch-rates were calculated as the number of individuals collected per hour of electrofishing (CPUEN) and as weight in pounds collected per hour of electrofishing (CPUEw). Catch data, both numbers of individuals and pounds collected per sample and hour, were summarized and reported by collection site. Data from sites also were grouped into reaches defined by navigation dams (Figure ) as follows: Alton Reach, river mile (RM) -8; La Grange Reach, RM 8-58; Peoria Reach, RM 58-3; Starved Rock Reach, RM 3-47; Marseilles Reach, RM 47-7.5; and Dresden Reach, RM 7.5-86 on the Des Plaines River. Data from reaches were combined further into three groups (lower and middle Illinois River segments, and the upper illinois Waterway segment) cefined by their iocaionr along the river and by the 3
amount of off-channel habitat accessible to fish per unit length of river (Lerczak et al. 994 and Figure ). Lerczak et al. (994, 995, and 996) showed that river fish communities of the three segments differed substantially enough to give segment designations biological meaning. RESULTS AND DISCUSSION (Job 4) Before the fish sampling season began, all equipment was tested and repaired as necessary, and staff were given a review in safety procedures and electrofishing methods (Job ). All 8 sites were sampled between 7 August and 3 September (Job ); total sampling time was 7. h (Table ). Collected data were entered into Microsoft ACCESS, and verified against original field data sheets until no errors were detected (Job 3). The original data sheets from this year's sampling and all of the other original data sheets of this project (957-) are stored in flame-resistant cabinets at the Illinois River Biological Station at 74 N. Schrader Avenue, Havana (Job 3). A. CONDITIONS DURING ELECTROFISHING RUNS Sampling was conducted in full daylight between 8:3 AM and :3 PM (Table ). The ranges for physical measurements collected during the sampling season were as follows: air temperature, 5.4-89.7 OF; water temperature, 74.-84.6 OF; dissolved oxygen concentration, 4.-9.4 ppm; Secchi disk transparency, 5.-8.3 in; conductivity, 366-8 umhos/cm; surface velocity,.-.3 ft/s; water depth,.3-7. ft. 4
All values were within the ranges expected based upon previous sampling (see Lerczak et al. 994; Koel and Sparks, 999). All sites were sampled within our established water temperatures and river levels (Table ) within our established criteria (see Lerczak et al. 994). B. ELECTROFISHING RESULTS The following data summaries proceed through several levels of detail. First, data on the numbers of individual fish (by species) collected at each of the 8 sites are presented. Then, catch rates of the number of individuals collected per hour of electrofishing are calculated for each of the seven navigation reaches. Similar summaries are presented for fish weights. Results conclude with fish health as determined by external visual inspection. Common names used throughout this report follow Robins et al. (99). Common and scientific names are listed in APPENDIX A. Numbers of Fish Collected We collected a total of 4,565 fish representing 5 species (plus two hybrids) from families during 7h of sampling at 7 sites on the Illinois Waterway and a single site on the Mississippi River in. Gizzard shad was the most abundantly collected species, representing 3.4% of the total catch, followed by bluegill (8.%), emerald shiner (.%), bullhead minnow (6.8%), freshwater drum (5.5%) and green sunfish (4.4%). Bluegill and common carp were collected at 7 sites, gizzard shad and channel catfish were collected at 6 sites, freshwater drum were collected at 5 sites, largemouth bass were collected at 4 sites, and black crappie were collected at 3 sites. The sample from Lambie's Boat Harbor (RM 7.3, Peoria Reach) yielded the 5~
Table. Numbers of individuals of each fish species collected on the Mississippi River (Brickhouse Slough) and the lower Illinois River (Alton Reach, RM -8) in. Clupeidae gizzard shad threadfin shad Cyprinidae common carp Miss. River River Mile and Hours Fished Lower Illinois River Mile. 9. 4.7 6.8 3. 58.3 75.3 Total Species Effort.......75 5.75 common carp x goldfish emerald shiner red shiner silver chub Atherinidae brook silverside Catostomidae bigmouth buffalo river carpsucker shorthead redhorse smallmouth buffalo Ictaluridae channel catfish flathead catfish Moronidae white bass Centrarchidae black crappie bluegill green sunfish largemouth bass orangespotted sunfish warmouth white crappie Sciaenidae 36 3 7 3 4 7 3 3 4 33 98 49 4 8 3 5 3 3 6 4 5 3 3 4 6 3 7 8 3 freshwater drum 8 3 5 7 7 5 37 Total individuals 6 44 57 75 77 65 6 434 Total species/hybrids 6/ / / / 5/ / 6/ 9/ 6 5 4 4 43 3 6
Table 3. Numbers of individuals of each fish species collected on La Grange Reach (RM 8-58) of the middle Illinois River (RM 8-3) in. Clupeidae River Mile and Hours Fished La Grange Reach Middle Mile 86.5 95. 7 3 48 55. Total Total Species Effort.....75. 5.75 3.75 gizzard shad 54 9 77 5 skipjack herring 3 3 3 threadfin shad 3 Cyprinidae bullhead minnow 4 common carp 3 8 8 5 38 39 common carp x goldfish 3 4 6 emerald shiner 4 8 goldfish 5 6 9 grass carp 3 red shiner 5 silver carp spottail shiner 5 Catostomidae bigmouth buffalo 3 5 34 river carpsucker 47 short head redhorse 4 smallmouth buffalo 4 5 84 Ictaluridae channel catfish 4 6 5 9 8 34 6 black bullhead 4 flathead catfish 3 8 freckled madtom Moronidae white bass 4 3 4 6 38 95 yellow bass Centrarchidae black crappie 8 6 8 7 bluegill 4 6 3 6 5 449 bluegill x green sunfish green sunfish 5 4 largemouth bass 6 45 orangespotted sunfish white crappie 3 3 5 Percidae sauger 6 Sciaenidae freshwater drum 3 5 6 6 7 97 5 Total Individuals 4 5 99 74 45 59 44 389 Total species/hybrids 3/ 5/ 7/ 6/ / / 9/ 4/ River
Table 4. Numbers of individuals of each fish species collected on Peoria Reach (RM 58-3) of the middle Illinois River (RM 8-3) in. River Mile and Hours Fished Peoria Reach Middle River Mile 63.3 7.3 8.6 93.8.8 3.3 7.6 5.3 Total Total Species Effort........ 8. 3.75 Clupeidae gizzard shad threadfin shad Cyprinidae bullhead minnow common carp common carp X goldfish emerald shiner goldfish grass carp red shiner silverband shiner silverchub spottail shiner Catostomidae bigmouth buffalo black buffalo golden redhorse river carpsucker shorthead redhorse silver redhorse smallmouth buffalo Ictaluridae black bullhead channel catfish flathead catfish yellow bullhead Lepisosteidae shortnose gar Moronidae white bass Centrarchidae black crappie bluegill bluegill X green sunfish green sunfish largemouth bass orangespotted sunfish smallmouth bass warmouth white crappie Percidae logperch sauger slenderhead darter 7 7 7 4 95 5 6 8 4 4 3 8 7 4 7 74 5 8 38 6 8 5 I 8 5 I 3 3 I I 3 7 4 8 3 8 57 95 8 6 66 4 4 8 4 6 8 Sciaenidae freshwater drum 43 4 9 4 3 5 3 7 8 5 Total individuals 78 4 33 5 5 8 7 9 9 389 Total species/hybrids 5/ / 9/ / 4/ 8/ / / 38/ 4/ 8 9 3 5 3 3 5 6 5 3 5 3 4 6 3 4 4 7 8 3 8 5 7 3 47 3 4 6 4 9 36 3 73 3 8 3 4 399 9 39 8 5 4 39 6 9 3 5 6 5 34 47 4 84 4 6 7 449 4 45 5 5
most fish (95,.% of the total collected from all 8 sites). The most species collected at one site was, also obtained from Lambie's Boat Harbor on the Peoria Reach. The fewest species collected at a single site was six from Moore's Towhead (RM 75.3) in Alton Reach. The sample from Mortland Island (RM 9., Alton Reach) yielded the fewest fish at 44. Of the 5 species and two hybrid crosses, sixteen species (brook silverside, freckled madtom, golden shiner, highfin carpsucker, logperch, longear sunfish, western mosquitofish, northern hogsucker, rockbass, silver carp, shortnose gar, skipjack herring, striped shiner, silver redhorse, yellow bullhead, and yellow bass) were collected at only a single site; whereas, four species (black buffalo, black bullhead, blackstripe topminnow, grass carp, and slender head darter) were collected at only two sites. Eleven species (black buffalo, brook silverside, freckled madtom, golden shiner, logperch, mosquitofish, northern hogsucker, slenderhead darter, shortnose gar, silver redhorse, and yellow bass) were represented by single individuals at sites, and a maximum of two individuals were collected at sites for each of seven species (golden redhorse, grass carp, highfin carpsucker, longear sunfish, silver carp, and yellow bullhead). On the 7 Illinois Waterway sites we collected 4,459 fish representing 5 species (plus two hybrids) from families during 6. h of sampling. At Brickhouse Slough on the Mississippi River (RM 4.9), we collected 6 fish representing 6 species from seven families (Table ). This year's sample from Brickhouse Slough was comparable with the data (McClelland and Pegg. ), but was considerably lower when compared with other semples collected at this site since 989 (see Lerczak et al. 9
994,995, 996; Koel et al. 998; Koel and Sparks 999). On the lower Illinois River, we collected 434 fish representing 9 species plus one hybrid (Table ). In, species richness ranged from 6 at Moore's Towhead (RM 75.3) to 5 at Crater-Willow Islands (RM 3.). Although species richness was lowest at Moore's Towhead, catch was highest there at 6 total fish. However, most of the fish collected at Moore's Towhead were a single species (98 gizzard shad), explaining the high total catch and low species richness. This is the fourth year fish were collected at Moore's Towhead. This site is a main channel border with very little structure and could explain the lower species richness at this site. We collected 389 fish species representing 4 species plus two hybrids (Tables 3 and 4) on the middle Illinois River. From six sites on La Grange Reach (RM 8-58), 44 fish representing 9 species plus two hybrids (common carp x goldfish, bluegill x green sunfish) were collected and from eight sites on Peoria Reach (RM 58-3), 9 fish representing 38 species and two hybrids (common carp x goldfish, bluegill x green sunfish) were collected. Species richness ranged from at Pekin (RM 55., La Grange Reach) to at Lambie's Boat Harbor (RM 7.3, Peoria Reach) in. This is the highest species richness recorded in F--R sampling at Lambie's Boat Harbor. A previous high of species was recorded here in 996 (Koel et al. 997). In addition to species richness, Lambie's Boat Harbor was also the site of highest total catch on the middle river with 4 total fish collected. This is the highest number of fish ever collected in F--R sampling for any single site and more than doubles the previous high catch for Lambie's Boat Harbor with 547 fish recorded in 995 (Lerczak et al. 996). Previous high catch for any single site throughout the Illinois Waterway
Table 5. Numbers of individuals of each fish species collected on Starved Rock, Marseilles, and Dresden Reaches of the upper Illinois Waterway (RM 3-8) in. River Mie and Hours Fished Upper Waterway Starved Rock Marseilles Dresden Total Mile 4.8 4.5 48 49.6 6.6 77.3 79.8 Species Effort....5... 6.5 Clupeidae gizzard shad 7 48 8 3 44 Cyprinidae bullhead minnow 3 9 8 5 94 66 36 common carp 4 4 3 4 common carp x goldfish emerald shiner 3 4 48 57 4 5 golden shiner silver chub 3 spotfin shiner 66 4 3 5 57 spottail shiner 3 striped shiner 3 3 Catostomidae black buffalo golden redhorse 4 highfin carpsucker northern hogsucker river carpsucker smallmouth buffalo 7 6 4 Ictaluridae channel catfish 4 5 3 6 flathead catfish Moronidae white bass Centrarchidae black crappie bluegill 9 5 5 8 8 39 37 bluegill X green sunfish 3 8 3 6 green sunfish 5 4 3 6 3 9 largemouth bass 3 7 6 8 47 longear sunfish orangespotted sunfish 9 rock bass 9 9 smallmouth bass 3 5 3 7 Sciaenidae freshwater drum 3 Poeciliidae western mosquitofish Fundulidae blackstripe topminnow 3 5 Total individuals 59 48 437 9C 7 37 56 74 Total species/hybrids 3/ 9/ 6/ 8/ 6/ 4/ 6/ 9/
was 897 fish collected at Bull's Island Bend (RM 4.5, Starved Rock Reach) in 995 (Lerczak et al. 996). Species richness at Hennepin Island (RM 7.6, Peoria Reach) and Henry Island (RM 93.8, Peoria Reach) were also the highest ever recorded in F- -R sampling for those sites, with species collected at both sites. Total catch at Lower Peoria Lake (RM 63.3, Peoria Reach) was also the highest recorded in F--R sampling with 78 fish collected, while the sample at Upper Bath Chute (RM 3., La Grange Reach) was the lowest recorded for that site at 8 total fish. We collected 74 fish representing 9 species plus two hybrid crosses (common carp x goldfish, bluegill x green sunfish) (Table 5) on the Upper Waterway in. Species richness ranged from 8 at Johnson Island (RM 4.8) to 9 at Bull's Island Bend (RM 4.5). The 8 species collected at Johnson Island is one of the lowest recorded along with species numbers from 998 (7 species) and 993 (6 species). However, a total catch of 98 fish is higher than most years (Lerczak et al. 994; Koel et al. 999). The total catch observed at Ballard's Island was 43 in and is the second highest recorded for this site in F--R. The highest total catch was 47 fish collected in 995 (Lerczak et al. 996). Catch Rates in Numbers of Individuals Collected per Hour by Reach. In the following data summary, discussion is restricted either to species that each separately accounted for over % of the total catch or to species that were of special significance. Alton (lower river). The 95% lists (species were added to the list until 95% of the total catch in numbers was obtained) for Alton, La Grange, and Peoria
Table 6. Numbers of individuals of each fish species collected per hour of electrofishing (CPUEN) on Reach 6 of the Mississippi River (Brickhouse Slough) and on six reaches of the Illinois River Waterway in. Reach and Hours Fished Starved Overall Reach 6 Alton La Grange Peoria Rock Marseilles Dresden CPUEN Species. 5.75 5.75 8...5. 7. Clupeidae gizzard shad skipjack herring threadfin shad Cyprinidae bullhead minnow common carp common carp X goldfish emerald shiner golden shiner goldfish grass carp red shiner silver carp silver chub silverband shiner spotfin shiner spottail shiner striped shiner Catostomidae bigmouth buffalo black buffalo golden redhorse highfin carpsucker northern hogsucker river carpsucker shorthead redhorse silver redhorse smallmouth buffalo Ictaluridae channel catfish black bullhead flathead catfish freckled madtom yellow bullhead Lepisosteidae shortnose gar Moronidae white bass yellow bass I 36. 5.9 3.39.5.7.5. 4..7 4. 3.65 3...35 6.6.7.39.4.7.7.7.35.35.7.7.5.87 34.5 3.5 5..5..5.6.5.5.6.5.5.9 4.5.7.7.37.3.87.9 9. 4..35 5.9.7..9.39.7. 3.65 6.6.7 9.5 34.8 f.5 4..4 7.5 7..3.75..4 53. 8..5.5 4.8 3.5.37.38.5..5.. 7...8 4..4.4.4.5 4.5...4 54.8..56 8..48 3.5 6.78.5.33 49.5.59.5.4.7...7.6..5 5.78.67.5..37.7..7.4.93.9.4 3.85 5.67.5.93.4.7.4 4.44.4
Table 6. (continued) Numbers of individuals of each fish species collected per hour of electrofishing (CPUEn) on Reach 6 of the Mississippi River (Brickhouse Slough) and on six reaches of the Illinois River Waterway in. Reach and Hours Fished Starved Overall Reach 6 Alton La Grange Peoria Rock Marseilles Dresden CPUEN Species. 5.75 5.75 8...5. 7. Centrarchidae black crappie bluegill bluegill X green sunfish green sunfish largemouth bass longear sunfish orangespotted sunfish rock bass smallmouth bass warmouth white crappie Percidae logperch sauger slenderhead darter Sciaenidae freshwater drum Atherinidae brook silverside Poeciliidae western mosquitofish Fudulidae 7..43 4.87 5.5.5.. 3.74. 7.48 8.7 49.87 335. 3. 83.5 3.7.7... 5..93 3..7.7.5 9.5 6.4 8.5 7.4 4. 4..4 4.87. 3.6 7. 4.4.8.7 7..35.5 3.6 6..78 3...7.63.5.5.75..35.5.5 8. 6.43 6.87 3.5.5.7 4.5.33.5.8.5.8.8...4..7 9.37.4.5.4 blackstripe topminnow.5.9 Total Number per hour 6. 75.48 78.43 77.37 53.5 4.8 33. 83.37 Number of species/hybrids 6/ 9/ 9/ 36/ 9/ / 8/ 5/
Table 7. Species ranks by relative abundance (number of fish collected per hour) for on the 6 reaches of the Illinois Waterway. Species were added to the list in descending order of abundance until 95% of the total catch for that reach was obtained. Percentages are in parentheses. Rankings by Reach Starved Species Alton La Grange Peoria Rock Marseilles Dresden Clupeidae gizzard shad skipjack herring threadfin shad Cyprinidae bullhead minnow common carp common carp x goldfish emerald shiner goldfish spotfin shiner spottail shiner Catostomidae bigmouth buffalo river carpsucker smallmouth buffalo Ictaluridae channel catfish flathead catfish Moronidae white bass Centrarchidae black crappie bluegill bluegill x green sunfish green sunfish largemouth bass orangespotted sunfish rock bass white crappie Sciaenidae (5.9) 5 (4.) 7 (3.6) (.3) (.) 7 (3.6) 9 (.4) 3 (7.5) 5 (4.) (3.4) 6(.5) 6(.5) 4(6.6) 5 (.7) (.4) (.) 4(.9) 8 (.9) 8 (.9) 6 (5.9) (.4) 4 (6.6) 7 (4.9) 3 (8.7) (.) 6(.5) (34.) 4(3.5) 4(.6) (3.6) (4.5) 6(9.) (3.5) 7(7.) 8 (5.) (49.9) 5(.5) 9 (4.9) 3 (.) freshwater drum 4 (6.4) (6.8) 3 (3.5) Number of species accounting 5 (9.5) (7.5) (53.) 8 (4.) 7 (4.5) 3 (35.) 6 (9.5) 9 (3.6) 9 (3.6) 5 (5.) (34.8) 8 (4.) 5 (.5) (8.) (3.5) (7.) 3 (49.5) 4(8.) 7 (4.8) 3 (3.) for 95 % of total catch 8 3 6 (6.4) 9 (3.6) 9 (3.6) (83.5) 8 (5.) 4 (8.5) 6(7.) 7 (6.) 9 (4.5) '..
Reaches remained similar to each other, as in past years, although total catch in numbers per hour (CPUEN) varied within reaches. Ten species accounted for 95.% of the total catch in Alton Reach (Tables 6 and 7) and overall, CPUEN was 75.48 in. This is well below catch rates observed in previous years, however, the lowest CPUEN of 75.5 occurred in 99 and a high CPUEN of 66.6 occurred in 997 (Lerczak et al. 994, 995, 996; Koel et al. 997, 998; Koel and Sparks, 999; Arnold et al. ; McClelland and Pegg, ). The highest CPUEN for an individual species was 5.9 for gizzard shad, which made up 3.% of the total fish collected in this reach. Channel catfish ranked second with a CPUEN of.35 (6.4% of the total), and bluegill ranked third with a CPUEN of 7.48 (9.9% of the total). La Grange (middle river). Eighteen species accounted for 95.3% of the total catch in La Grange Reach (Tables 6 and 7). Overall, CPUEN was 78.43, the lowest catch in number since 99 when a CPUEN of 73. was observed (Lerczak et al. 993). The highest CPUEN occurred in 996 (34.9) (Koel et al. 997). In, the highest CPUEN for any species was 6.87 for freshwater drum, which made up.% of the total fish collected in this reach. Gizzard shad ranked second with a CPUEN of 3.39 (7.46% of the total). Gizzard shad have ranked in the top three species for catch in number more than any other fish in the La Grange Reach, however this is the second lowest CPUEN recorded for gizzard shad. The lowest catch in number for gizzard shad was 5.8 recorded in 99 (Lerczak et al. 993). Bluegill ranked third with a CPUEN of 8.7 (.33% of the total). Common carp ranked fourth in with a CPUEN of 6.6. This is the second straight year in which common carp catch rates have not ranked in the top three in La Grange Reach Two Silver carp were collected
for the first time in F--R sampling in the La Grange Reach at Lower Bath Chute (RM 7.) and a freckled madtom was collected for the second time in La Grange Reach at Pekin (RM 55.). Peoria (middle river). Thirteen species accounted for 94.8% of the total catch in Peoria Reach (Tables 6 and 7). Overall, CPUEN was 77.37. This is one of the highest catch rates observed in the Peoria Reach. Previous high catch rates of 9. and 85.57 were observed in 995 and 996, respectively (Lerczak et al. 996; Koel et al. 997). The highest CPUEN for any species was 34.5 for gizzard shad, which made up 48.4% of the total fish collected in this reach. This represents the second highest catch rate ever recorded for gizzard shad in the Peoria Reach. Bluegill ranked second in with a CPUEN of 49.87 (7.98% of the total). This is also the second highest catch rate recorded for bluegill in the Peoria Reach, with a previous high catch rate of 5.63 recorded in 999 (Arnold et al. ). Bluegill have ranked among the top two species since 99 in the Peoria Reach (Lerczak et al. 993, 994, 995,996; Koel et al. 997,998,999; Arnold et al. ; McClelland and Pegg,). Freshwater drum ranked third with a CPUEN of 3.5 (4.9% of total). Silver redhorse were collected for the first time in the Peoria Reach, a single individual was collected at Lambie's Boat Harbor (RM 7.3). A single shortnose gar was collected for the second time in F--R sampling in the Peoria Reach at Lower Peoria Lake (RM 63.3). An individual was previously collected in 995 at Clark Island (RM 5.3) (Lerczak et al. 996). Starved Rock (upper river). Ten species accounted for 94.5% of the total catch
in Starved Rock Reach (Tables 6 an 7). Overall, CPUEN was 53.5 in. This catch rate is down considerably from, but still the third highest CPUEN recorded in F- -R sampling. Emerald shiner, spotfin shiner, and bluegill were the top three ranked species composing 6.9% of the catch. The highest CPUEN for any species was 7.5 for emerald shiners comprising 8.% of the total catch. Spotfin shiner ranked second with a CPUEN of 53. (.9% of total). This is the only the second year that spotfin shiner have been documented on the Starved Rock Reach during the fourteen segments of project F--R. They were previously collected in 998 at Bull's Island Bend (RM 4.5), but in were collected at both sites in the Starved Rock Reach (Koel et al. 999). Bluegill ranked third with a CPUEN of 35. (3.8% of total). Black Buffalo were collected for the first time in F--R sampling in Starved Rock Reach where a single individual was collected at Bull's Island Bend. Marseilles (upper river). Ten species accounted for 94.6% of the total catch in Marseilles Reach (Tables 6 and 7) and overall CPUEN was 4.8 in. The highest CPUEN for any species was 7. for emerald shiner, consisting of 44.% of the total fish collected at this reach. This is the highest CPUEN ever recorded for any species in the Marseilles Reach for F--R sampling. Emerald shiners have been among the top three fish species collected for the Marseilles Reach every year of F- -R sampling except for 996 (Koel et al. 997). Bullhead minnow ranked second with a CPUEN of 34.8 (4.3% of total). Bluegill ranked third with a CPUEN of 3. (3.% of total) and spotfin shiner ranked fourth with a CPUEN of 8. (7.4% of total). As with the Starved Rock Reach, this was the second documented occurrence of spotfin shiner in the Marseilles Reach during the fourteen segments of project F--R.
Northern hogsucker were also collected for the second time in Marseilles Reach, while flathead catfish and silverchub were collected for the first time in. Northern hogsucker, flathead catfish, and silverchub were all collected at a single site, Waupecan Island (RM 6.6), while spotfin shiners were collected at all three Marseilles Reach sites. Dresden (Des Plaines River). Ten species accounted for 95.% of the total catch in Dresden Reach (Tables 6 and 7). Overall, CPUEN was 33. in. This catch rate is down from the CPUEN of 44.5 observed in and 6. observed in 995, but remains higher than the CPUEN observed for all other years of F- -R sampling. In, the highest CPUEN for any species was 83.5 for bluegill, which made up 6.7% of the fish collected. This is the second highest catch rate for bluegill in the Dresden Reach since the beginning of project F--R. The highest catch rate was recorded in with a CPUEN of 3.. Bullhead minnow ranked second with a CPUEN of 8. (5.7% of total). Emerald shiner ranked third with a CPUEN of 49.5, making up 5.8% of the catch. This is the highest catch rate observed for emerald shiner on the Dresden Reach since 993 when a CPUEN of 49.5 was also recorded. Although largemouth bass did not rank high in abundance, the catch rate of 7. observed in was the highest recorded in F--R sampling for this species. In addition, mosquitofish and spotfin shiner were collected for the first time in Dresden Reach, and striped shiner were collected for the second time. Mosquitofish and striped shiner were collected at Treat's Island (RM 79.8), while spotfin shiner were collected at the Mouth of the DuPage River (RM 77.3).
Catch Rates in Weights (pounds) Collected per Hour by Reach. The following data summary and discussion is restricted to species that individually accounted for over % of the total catch and to species that were of special interest. A 95% list was produced for each reach, in which species were ranked by relative biomass (pounds per hour) and added to the list until 95% of the total catch rate in weight for that reach was obtained. Overall, these data indicate that in terms of biomass the fish communities of the Illinois River continue to be dominated by common carp, bigmouth buffalo, and channel catfish in the lower and middle river, and common carp, smallmouth buffalo, gizzard shad, and channel catfish in the upper waterway. Alton (lower river). Eight species accounted for 94.4% of the total catch by weight in pounds per hour (CPUEw) in Alton Reach (Tables 8 and 9) in. Overall CPUEw was 3.95. This catch weight is the lowest observed in Alton Reach since the beginning of F--R sampling. Channel catfish CPUEw was the highest at.6 (39.% of total); compared to a CPUEw of 4.4 in (McClelland and Pegg ). Common carp ranked second with a CPUEw of 7.6 (7.9% of total) and bigmouth buffalo with a CPUEw of.93 (7. % of total). Largemouth bass CPUEw ranked fourth at.86 (6.8% of total). La Grange (middle river). Nine species accounted for 94.7% of the total catch by weight in La Grange Reach (Tables 8 and 9) in. Overall, CPUEw was 69.5. Common carp was once again the top ranked species in total catch in weight on La Grange Reach with a CPUEw of 4.8 (39.9% of total). Channel catfish ranked second with a CPUEw of 7.49 (.% of total) and bigmouth buffalo ranked third at 3.
. 5.75 5.75 8...5. Table 8. Pounds of each fish species collected per hour of electrofishing (CPUEw) on Reach 6 of the Mississippi River (Brickhouse Slough) and on six reaches of the Illinois River Waterway in. Pounds per hour less than. but greater than zero are indicated by.. Reach and Hours Fished Starved Species Clupeidae gizzard shad skipjack herring threadfin shad Cyprinidae bullhead minnow common carp common carp X goldfish emerald shiner golden shiner goldfish grass carp red shiner silver carp silver chub silverband shiner spotfin shiner spottail shiner striped shiner Catostomidae bigmouth buffalo black buffalo golden redhorse highfin carpsucker northern hogsucker river carpsucker shorthead redhorse silver redhorse smallmouth buffalo Ictaluridae black bullhead channel catfish flathead catfish freckled madtom yellow bullhead Lepisosteidae shortnose gar Moronidae white bass yellow bass Overall Reach 6 Alton La Grange Peoria Rock Marseilles Dresden CPUE A..................%........5.36.5... 4.77..7.49 3.67.6.8. 7.6 4.8.4......3.5..6...93 3..3.7.6.9..75.. 7.7.5..33.5.... 8.8.7.9.3 3.98..38.6.37.9. 7.49.7....6 5.6.73..7 3.8 3..6 4.3.8..9..39.38.39 5.77 4...65. 7.8.33.35..5.3.4.6.7 3.63.8.49..4 6.98.4.6.3...3 3.8.48...3 4.58..6...48..5..... 3.55...3..37.. 4.4. 6.4.9....6.
Table 8. (continued) Pounds of each fish species collected per hour of electrofishing (CPUEw) on Reach 6 of the Mississippi River (Brickhouse Slough) and on six reaches of the Illinois River Waterway in. Pounds per hour less than. but greater than zero are indicated by.. Reach and Hours Fished Starved Overall Reach 6 Alton La Grange Peoria Rock Marseilles Dresden CPUE Species., 5.75 5.75 8...5. 7. Centrarchidae black crappie..65.99.5.4.36.4.85 bluegill.93.3.9.3.59.7 4.8.6 bluegill X green sunfish...5..3.7 green sunfish.5...83.9..76.34 largemouth bass.8.86.36 3.88.5.5 4.4.94 longear sunfish.4. orangespotted sunfish.4..3..4. rock bass.6.5 smallmouth bass.5.6.6.5. warmouth.4..3. white crappie.6..9.3 Percidae logperch.. sauger.3.3. slenderhead darter.. Sciaenidae freshwater drum..88.7.9.6.6.6 Atherinidae brook silverside.. Poeciliidae western mosquitofish.. Fundulidae blackstripe topminnow.. Total pounds per hour 7.8 3.95 7.5 85.88 3.9 5. 37.3 7.34
Table 9. Species ranked by relative biomass in pounds of fish collected per hour for. Species were added to the list in descending order of abundance until 95% of the total catch for that reach was obtained. Percentages are in parentheses. Species Clupeidae gizzard shad Cyprinidae bullhead minnow common carp common carp x goldfish emerald shiner grass carp silver carp Catostomidae bigmouth buffalo black buffalo golden redhorse highfin carpsucker river carpsucker shorthead redhorse smallmouth buffalo Ictaluridae channel catfish flathead catfish Moronidae white bass Centrarchidae black crappie bluegill green sunfish largemouth bass rock bass smallmouth bass white crappie Rankings by Reach Starved Alton La Grange Peoria Rock Marseilles Dresden (7.6) 3 (.93) 8 (.7) 9 (.75) (4.8) (7.7) 8(.6) 3 (3.) 6(.37) (.6) (7.49) 5 (.9) 5 (.7) 6 (.) 7(.) 4 (.86) 9 (.99) (.5) 3 (8.8) 5 (3.98) (.9) 4 (5.6) 7 (3.8) (.5) (.3) 6 (3.88) 4(3.) (4.3) 5(.39) 9 (.38) 8 (.39) (5.77) 3(4.) 6 (.59) 7 (.5) (.6) 5(.65) (7.8) 6(.33) 7 (.7) (3.63) 3 (.8) (.49) (.36) 7 (.7) 4 (.5) Sciaenidae freshwater drum 7 (.88) 4 (.7) 8 (.9) 9 (.6) Number of species accouting for 95% of total catch 8 9 9 5(.) (6.98) 6(.3) 4 (3.8) 3(4.8) 7 (.76) (4.4) 8(.6) 9 (.5)
(8.8% of total). Common carp, bigmouth buffalo, and channel catfish have ranked in the top three for 7 of the last 8 years (Koel et al. 997, and 998; Koel and Sparks, 999; McClelland and Pegg,). CPUEw for largemouth bass on the La Grange Reach prior to 996 varied but typically had been about 5 pounds per hour (Lerczak et al. 993,994,995,996). CPUEw for largemouth bass has been well below 5 pounds per hour for the last five of six years (996, 997, 998, 999, ) of project F--R (Koel et al. 997, 998; Koel and Sparks, 999; Arnold et al. ; McClelland and Pegg ), and in the catch weight for largemouth bass (.36) was the lowest ever recorded. Peoria (middle river). Nine species accounted for 94.8% of the total catch by weight in Peoria Reach (Tables 8 and 9). Overall, CPUEw was 85.88. This is the highest catch weight recorded for all reaches of the Illinois River in. The highest species specific CPUEw was 7.7 for common carp, which made up 35.6% of the total catch in weight for this reach in. Smallmouth buffalo ranked second with a CPUEw of.9 (3.% of total) and bigmouth buffalo ranked third with a CPUEw of 8.8 (.6% of total). Common carp, bigmouth buffalo, and smallmouth buffalo have been the top three species since 994 (Lerczak et al. 995,996; Koel et al. 997,998; Koel and Sparks 999; Arnold et al. ; McClelland and Pegg,). Channel catfish ranked fourth with a CPUEw of 5.6 (7.% of total). Starved Rock (upper river). Ten species accounted for 95.5% of the total catch by weight in Starved Rock Reach (Tables 8 and 9). Overall, CPUEw was 3.9 in. The highest CPUEw for any species was 5.77 for smallmouth buffalo, which
made up 6.3% of the total. Common carp ranked second with a CPUEw of 4.3 (9.7% of total) and channel catfish ranked third with a CPUEw of 4. (9.% of total). Marseilles (upper river). Eleven species accounted for 94.8% of the total catch by weight in Marseilles Reach (Tables 8 and 9). Overall, CPUEw was 5. and is similar to catch weights obtained from this reach during previous years (Lerczak et al. 994, 995, and 996; Koel et al. 997 and 998; Koel and Sparks, 999; Arnold et al. ; McClelland and Pegg, ). Common carp CPUEw was highest at 7.8 (34.6% of total). Smallmouth buffalo ranked second with a CPUEw of 3.63 (6.% of total) and channel catfish ranked third with a CPUEw of.8 (9.% of total). This is the highest CPUEw observed for channel catfish in the Marseilles reach since 997 when it was 3.(Koel et al. 998). Largemouth bass ranked fourth with a CPUEw of.5 (9.% of total) and remains comparable to the CPUEw observed since 995 (Lerczak et al. 996, Koel et al. 998; Koel and Sparks 999; Arnold et al. ; McClelland and Pegg,). Dresden (Des Plaines River). Nine species accounted for 95.4% of the total catch by weight in Dresden Reach (Tables 8 and 9). Overall, CPUEw was 37.3. The highest CPUEw for any species in was 4.4 for largemouth bass, which made up 44.4% of the total. This is the highest CPUEw recorded for largemouth bass on the Dresden Reach and all other reaches since F--R was initiated; while the previous high CPUEw for largemouth bass in all reaches of F--R was 8. recorded in the La Grange Reach in 99 (Lerczak et al. 994, 995, and 996; Koel et al. 997 and 998; Koel and Sparks, 999; Arnold et al., McClelland and Pegg,).
Common carp ranked second with a CPUEw of 6.98 (9.6% of total) and bluegill ranked third with a CPUEw of 4.8 (.8% of total). This is the highest catch in weight for bluegill in the Dresden Reach in all years of F--R sampling, and the second highest catch in weight for bluegill throughout all reaches for all years of F--R sampling. The high CPUEw for all reaches was 4.4 recorded in 99 in the La Grange Reach (Lerczak et al. 993). Fish Health Determined by External Visual Inspection. Sediment-contact (benthic) fishes (e.g., common carp) had higher incidences of externally visible abnormalities (e.g., sores, eroded fins) than water-column (pelagic) fishes (e.g., bluegill) (Figure ). A total of fishes had abnormalities, of which (83.3%) were sediment-contact fishes. The highest incidences of fish abnormalities occurred in the upper waterway where. % of benthic fishes had externally visible abnormalities. Occurrence of benthic fishes with abnormalities in the middle waterway was.3% and.7% in the lower waterway. Overall, percent benthic fishes with abnormalities were lower than abnormalities recorded during previous years of project F--R (Lerczak et al. 994, 995, and 996; Koel et al.997 and 998; Arnold et al., McClelland and Pegg,). The incidence of water-column fishes with abnormalities was absent among the upper and lower waterways. Two pelagic fishes (gizzard shad) in the middle waterway exhibited externally visible abnormalities (.% middle waterway pelagic fishes).
CONCLUSIONS Samples collected by electrofishing on the Illinois River Waterway during August, September, and October provided evidence of continued increase in species richness, catch rates, and a decrease in abnormalities. Ninety-six species and six hybrids have been collected since William Starrett began this survey in 957. Seventythree species and five hybrids have been documented by project F--R sampling (989-present); 5 species and two hybrids from twelve families were collected during 7. h of sampling in. Silver carp were again collected for the second time during project F--R sampling along the waterway; two specimens were collected on the La Grange Reach (middle river) at Lower Bath Chute. Peoria Reach continues to produce the highest number of species (38) along the waterway. This could be due, in part, to a greater number of sites in this reach, varied site types (backwater and side channel), and its position along the waterway, which includes the Great Bend (above Hennepin) of the Illinois River. This reach represents a transition from a river which is constricted, lacks contiguous backwaters, and is high in gradient (upper river) to a large river floodplain system with low gradient (lower river) (Sparks 977). The total weight of fishes collected was also highest in Peoria Reach, where CPUEw was 85.88 (Table 8). Species accounting for this high catch in weight were common carp, smallmouth buffalo, bigmouth buffalo, channel catfish, and river carpsucker. However, cetch weight was alsc relatively high in La Grange Reach. Of the,94. pounds of fish collected during our survey, 854.7 pounds (66.%) were collected from the middle river. The upper river produced 6.8 pounds (6.%) whii( the lower river produced.5 pounds (I 7 K% hes, catches reflect the high 3 7.-;,.