Fish
Status (continued)
Stinauer conducts a fish survey of the Illinois River and its backwater areas in 1974. Twenty-eight stations are established: 20 in the river channel and 8 in backwater lakes (Table 31).
Table 31: Sampling Station Locations (Stinauer 1974)
| Station No. | Water Area | County | Nearest Town |
| 1 | Illinois River | La Salle | Marseilles |
| 2 | Illinois River | La Salle | Marseilles |
| 3 | Illinois River | La Salle | Ottawa |
| 4 | Illinois River | La Salle | Utica |
| 5 | Illinois River | La Salle | Utica |
| 6 | Illinois River | Putnam | Hennepin |
| 7 | Illinois River | Marshall | Lacon |
| 8 | Illinois River | Marshall | Lacon |
| 9 | Woodford Co. Cons. Area | Woodford | Chillicothe |
| 10 | Illinois River | Peoria | Peoria |
| 11 | Illinois River | Tazewell | North Pekin |
| 12 | Illinois River | Tazewell | Pekin |
| 13 | Clear Lake | Mason | Liverpool |
| 14 | Goofy Ridge Ditch | Mason | Liverpool |
| 15 | Illinois River | Mason | Havana |
| 16 | Quiver Lake | Mason | Havana |
| 17 | Illinois River | Mason | Havana |
| 18 | Bath Shute | Mason | Bath |
| 19 | Sanganois Area | Mason | Browning |
| 20 | Myers Bay | Cass | Beardstown |
| 21 | Illinois River | Schuyler | Beardstown |
| 22 | Illinois River | Brown | LaGrange |
| 23 | Illinois River | Brown | LaGrange |
| 24 | Illinois River | Scott | Naples |
| 25 | Illinois River | Greene | Pearl |
| 26 | Dark Shute | Calhoun | Hardin |
| 27 | Illinois River | Calhoun | Batchtown |
| 28 | Illinois River | Jersey | Rosedale |
Water quality is examined at each sampling site. The pH is considered normal for all stations, ranging from 7.4 at Marseilles to 8.8 at Quiver Lake. The average pH is 8.0. Transparency is also tested using a Secchi disk. Rates ranged from 3 inches in Upper Peoria Lake to 14 inches at seven stations (2, 3, 4, 13, 14, 16, and 19), with the average being 8 inches. All waters are considered to be very turbid. Table 32 shows the results of the survey, including for each site the number of species collected, the degree and type of pollution found, the history of fish kills, pH, alkalinity and transparency (Stinauer 1974).
Table 32: Results of Fish Survey (Stinauer 1974)
| Station No. | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17* | 18 | 19* | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| No. of Species Collected | 14 | 21 | 16 | 16 | 27 | 23 | 23 | 25 | 32 | 24 | 22 | 18 | 14 | 15 | 14 | 18 | 8 | 13 | 12 | 14 | 14 | 12 | 12 | 15 | 19 | 12 | 16 | 21 |
| Pollution Severity: | ||||||||||||||||||||||||||||
| None | ||||||||||||||||||||||||||||
| Slight | ||||||||||||||||||||||||||||
| Moderate | ||||||||||||||||||||||||||||
| Heavy | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | ||||
| Chronic | X | X | X | X | ||||||||||||||||||||||||
| Types of Pollution: | ||||||||||||||||||||||||||||
| Mining | X | X | X | X | X | |||||||||||||||||||||||
| Industrial | X | X | X | X | X | X | X | X | X | X | ||||||||||||||||||
| Municipal | X | X | X | X | X | X | X | X | X | X | X | X | ||||||||||||||||
| Agricultural | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X |
| History of Fish Kills | X | X | X | X | X | X | X | X | X | X | X | X | ||||||||||||||||
| pH | 7.4 | 7.6 | 7.6 | 8.0 | 7.6 | 7.9 | 7.9 | 8.4 | 8.4 | 8.0 | 8.3 | 7.8 | 8.6 | 8.4 | 8.4 | 8.8 | 8.0 | 7.8 | 7.8 | 8.0 | 8.0 | 8.1 | 8.1 | 7.6 | 7.9 | 8.0 | 8.0 | 8.0 |
| Alkalinity | 170 | 176 | 170 | 174 | 176 | 180 | 160 | 280 | 176 | 180 | 176 | 158 | 200 | 210 | 244 | 200 | 224 | 212 | 235 | 214 | 200 | 220 | 220 | 162 | 170 | 198 | 192 | 170 |
| Transparency (Secchi-in) | 13 | 14 | 14 | 14 | 12 | 7 | 8 | 4 | 3 | 4 | 8 | 4 | 14 | 14 | 4 | 14 | 8 | 5 | 14 | 4 | 6 | 6 | 6 | 7 | 4 | 6 | 6 | 6 |
*Electro-fishing gear not used at this station
Sampling for this study is conducted between July 11 and October 19. A total of 11,917 fish are collected, consisting of 50 species and 3 hybrid species (Table 33). The gizzard shad is the most common, making up 34.3% of the total. The largemouth bass is the second most numerous at 15.5% of the total catch, carp is third at 12.0%, followed by black crappie at 6.1%, and bluegill at 5.2%.