Chautauqua anglers caught 295 largemouth bass 
(10 inches or longer), representing 21.9 per cent 
of the total 1950 catch of this species at the lake, 
table 4. During the normally closed period in 
1951, anglers caught 191 bass (all sizes), equal to 
17.3 per cent of the catch of bass for 1951. 
No actual observations of nesting bass were 
made in 1950 or 1951. On June 23, 1950, we took 
(in two hauls with a20-foot minnow seine) 65 young 
bass ranging in total length from 1.1 to 1.6 inches. 
These, and additional catches of young bass taken 
later in summer, furnished evidence that bass had 
spawned with some degree of success, even though 
fishing was not restricted during the spawning sea- 
son. Little evidence was found that bass produced 
a successful spawn in 1951, and in that year only 
191 bass were removed by anglers during the 
April 16 through May 31 period. Evidently some 
factor other than fishing affected the success of 
bass spawning in 1951. Murphy (1950) concluded 
from his studies in California that a closure of 
fishing during the spawning season of the 
largemouth bass did not increase the production of 
fingerling bass. 
Bennett (1951) found that where bass were 
given complete protection from fishermen during 
spawning, the numbers of bass fry surviving to the 
schooling stage varied inversely with the numbers 
of yearling bluegills present. 
In the spring of 1951 the 10-inch limit on 
largemouth bass was removed at Lake Chautauqua. 
Boat liverymen were furnished fish-measuring 
boards bearing a mark at 10 inches. They recorded 
on each angler’s fishing permit, fig. 3, whether the 
bass taken were less than 10 inches or were 10 
inches or longer. Of 737 bass measured in 1951, 
only 33.4 per cent were less than 10 inches. Length 
measurements made on bass caught by anglers in 
1950 indicated that 8.2 per cent of the fish were 
under 10 inches, even though the size-limit restric 
tion was in force. In 1951, some anglers were 
hesitant about keeping bass under 10 inches in 
length, even though signs had been posted at the 
boat yards advising that it was legal at Lake 
Chautauqua to keep bass of all sizes. Perhaps in 
the future more bass under 10 inches will be kept 
by anglers, as the 1951 legislature removed the 
size-limit restriction from the Fish Code. 
Discussion 
The anglers’ catches at Lake Chautauqua in 
1950 and 1951, table 2, demonstrate that satis- 
factory sport fishing may be found in the Illinois 
River valley for thousands of anglers. The Lake 
Chautauqua area, once a series of bottomland 
sloughs, then a drainage district surrounded by 
levees, is again a lake producing aquatic rather 
than terrestrial crops. 
Studies at Lake Chautauqua indicate that large 
populations of certain kinds of sport fishes are not 
harvested by anglers and that most of these fish 
die of old age. The sport-fish harvest would be 
greater if more anglers knew how to fish the lake. 
Anglers can enjoy good fishing at Lake 
Chautauqua by using tackle and fishing techniques 
that have been proved by experience. For example, 
artificial lures usually are ineffectual for taking 
the largemouth bass at Lake Chautauqua, but a 
cane pole and a hook baited with a large, live chub 
minnow takes this species quite readily. 
Every angler at Lake Chautauqua should talk 
over fishing conditions and methods with the liv- 
eryman from whom he rents a boat. The boat-yard 
liveryman is one person who usually knows what 
kind of fish are biting, the kind of bait to use, and 
where an angler is most likely to catch fish. 
The Lake Chautauqua angler who specializes 
in fishing for only one kind of fish may make poor 
catches during certain years because of a tempo- 
tary reduction in the abundance of that species. 
The perennially successful angler is the one 
who fishes for species that are abundant and are 
biting well. He knows that, even though a species 
is abundant in the lake, there is little use to fish 
for it under certain conditions. Some abundant 
species are difficult to catch except during their 
spawning periods, or at certain water stages or 
changes in levels, or at certain seasons of the year. 
Summary 
1. Lake Chautauqua is a reflooded drainage 
district in the flood plain of the Illinois River near 
Havana. It is being studied to discover the values 
of the sport and commercial fisheries of a bottom- 
land lake and the factors controlling these values. 
2. Since the flood of 1943, the lake has been 
more turbid and has contained less aquatic vegeta- 
tion than for several years previous. In 1950 a silt 
survey indicated that the storage capacity of Lake 
Chautauqua had been reduced 18.3 per cent by 
sedimentation in approximately 24 years. 
3. A creel census made at Lake Chautauqua 
between April 15, 1950, and October 25, 1951, 
showed that anglers caught 36,822 fish in 1950 and 
56,289 in 1951. Anglers’ catches included 25 dif- 
ferent kinds of fishes. 
29 
