236 ILLinois NATURAL 
the l-inch mesh, as thousands of small 
bluegills became gilled in the screen mesh. 
The fish impeded the flow of water 
through the screen and stopped draining 
operations until they could be removed. 
It became an impossible task to make any 
count of these young. For the 1951 
census the screen frames were covered 
with l-inch-mesh hardware cloth, and no 
attempt was made to estimate the num- 
bers of small bluegills less than 2 inches 
History Survey BULLETIN 
Vol. 26, Art. 2 
all in Illinois. Table 2 lists the lakes 
from which these bass were taken, the 
numbers, weights, and length ranges of 
the bass, and the dates of their introduc- 
tion into Ridge Lake. 
Before being released, all the bass were 
fin-clipped for later identification. From 
each Craborchard Lake bass, the left pec- 
toral fin was clipped, from each Lake 
Chautauqua bass, the right pectoral, and 
from each Lake Glendale bass, the dorsal. 
Table 2.—Source, number, weight, and length range of largemouth bass used in stocking 
Ridge Lake. 
Source oF Fisu | NuMBER pl seetidi rarest! pac 
OUNDS INCHES TO N 
Craborchard | Pies eas 58 24.1 6:5-11.5 | | Apri 
Lake Chautauqua........ 42 42.9 8.5-17.0 May 1, 1941 
Finke Glendale: ks... | 335 29.5 50-70 June 18, 1941 
EDEMA Bee RL Tis eens Se et 435 96.5 — — 
long that went through; however, to- No largemouth bass from _ outside 
ward the end of the draining operation 
a fine-mesh dip net, held in the flow below 
the screen for 1 minute, caught 381 smail 
bluegills weighing 2.75 pounds. 
As mentioned previously, fish were fin- 
clipped prior to their being returned to 
the lake following a census, fig. 11. The 
fin clipped in the 1943 census was the 
left pectoral; in the 1945 census the right 
pectoral; in the 1947 census the left 
pelvic; in the 1949 census the dorsal; 
and in the 1951 census the left pectoral. 
In each census, only the fish that had 
not been fin-clipped previously were 
marked. ‘Thus, all fish more than 22 
months old (except the few that as small 
fish had escaped capture by staying in the 
lake basin) bore marks that assigned them 
to specific 2-year periods; for example, 
a 3.5-pound bass caught in 1949 showed 
the left pectoral fin missing, which indi- 
cated that it had been spawned in 1941 or 
1942 and marked when being returned to 
the lake after the 1943 census. 
Population Dynamics 
The 435 largemouth bass with which 
Ridge Lake was stocked in 1941 were 
wild fish netted from Craborchard Lake 
near Carbondale, Lake Chautauqua near 
Havana, and Lake Glendale near Robbs, 
sources have been placed in Ridge Lake 
since the original +35 were introduced 
in 1941. Evidence presented later (pages 
265 and 266) indicates that many of these ~ 
original bass were sufficiently injured 
during netting operations or in transpor-— 
tation to Ridge Lake to cause them to- 
die within a short time after their intro- 
duction into the lake, particularly the 
Lake Glendale fish that were caught and | 
moved in June. 
Bluegills were first placed in Ridge 
Lake on June 27, 1944, when 107 of 
these fish, +.5 to 7.5 inches in length, were 
brought in from Lake Chautauqua. Of 
these, 7 were dead or dying on arrival, 
but 100 were released. Later in the same 
year, on July 13, 29 bluegills between 5_ 
and 6.5 inches in length were brought to— 
the lake from a strip-mine pond near 
Danville, Illinois. No weights were 
taken of either group of bluegills. From_ 
each Lake Chautauqua fish was clipped 
the left pectoral fin and from each Dan-— 
ville fish the right pectoral. No other 
stocks of bluegills have been introduced 
since these 129 were released in 1944, 
In April, May, and June of 1949, 
three groups of warmouths, Chaenobryttus 
coronarius (Bartram), totaling 138 fish 
were placed in Ridge Lake to test the 
ability of these fish to expand their popu-— 
