Interactions of Intensive Cultures of Channel Catfish 
With Largemouth Bass and Bluegills in 1-Acre Ponds 
ee << ~~O*s*sté=<“i:~‘i<CS~*s 
DEVELOPMENT OF techniques for the pond culture 
of channel catfish (Ictalurus punctatus), and increas- 
ing use of the species in both tropical and temperate 
climates, have stimulated interest in the feasibility of 
combining channel catfish production with other pond 
cultures. In an earlier study (Buck et al. 1972) we 
examined the compatibility of channel catfish and 
golden shiners (Notemigonus crysoleucas) in com- 
bined cultures. In the study reported here we have 
attempted to measure the nature of the interactions 
when intensive cultures of channel catfish were super- 
imposed upon existing populations of largemouth bass 
(Micropterus salmoides) and bluegills (Lepomis 
macrochirus ). 
DESCRIPTION OF PONDS 
The ponds used in these studies were originally 
constructed to be 100 feet (30.5 meters) wide and 
436 feet (132.9 meters) long, and to provide a 
surface area of 1.0 acre (0.4 hectare) when main- 
tained at maximum depths of 7 feet (2.13 meters). 
In the present study maximum pond depths fluctuated 
between 6 and 7 feet (1.8 and) 2.1 )meters )jeand 
average depths between 3 and 4 feet (0.9 and 1.2 
meters). Because of shoreline erosion over the period 
since the date of pond construction (1963), it is be- 
lieved that areas of 1.0 surface acre (0.4 hectare) 
were very closely approximated at the levels over 
which the depths fluctuated during the period of 
study. Water was supplied to the ponds by gravity 
from a 585-acre (236.7-hectare) reservoir. Drainage 
valves were contained in cement headwalls which 
supported short walkways out over the deepest parts 
of the ponds. 
1970 EXPERIMENTS 
Materials and Methods 
In April and May, 1970, six l-acre (0.4-hectare ) 
study ponds were each stocked with 635 3- to 6-inch 
(7.6- to 15.2-centimeter ) bluegills and 308 largemouth 
bass of mixed sizes and ages, including mature adults. 
We hoped that the initial stock could be sufficiently 
large to permit both species to attain carrying ca- 
pacities by fall. 
This paper is published by authority of the State of Illinois, 
IRS Ch. 127; Par, 58.12. It is a contribution from the Section 
of Aquatic Biology of the Illinois Natural History Survey. Dr. 
D. Homer Buck is an Aquatic Biologist, Richard J. Baur a Re- 
search Assistant, and C. Russell Rose a Field Assistant, all at 
the Survey. 
D. Homer Buck, Richard J. Baur, and C. Russell Ros 
In May and June we superimposed channel catfis 
populations of two types (all caged; and half cagec 
half free) upon four of the bass-bluegill population: 
The other two ponds were maintained as contro 
having only bass and bluegills. Two additional ponc 
were also maintained as controls with catfish onl 
half caged and half free. Thus, we had eight ponds - 
two with bass and bluegills only, two with catfish onh 
and two sets of two ponds each in which the catfis 
were combined with the bass and bluegills in tw 
different ways. 
Each catfish population was composed of 1,6( 
5-inch individuals of which 850 were stocked on Ma 
14 and 750 were stocked on June 11. In one of tl 
two types of catfish populations 800 of the fish we: 
released into the pond while the other 800 were co 
fined to cages; in the second type all 1,600 catfi 
were confined in two cages at rates of 800 per cage. 
a convenience, each pond containing catfish was co 
sidered to have two population units, those stock« 
at a rate of 800 free in the pond, or those stocked 
rates of 800 per cage. 
Cages used in this study were constructed by la 
ing %-inch (1.27-centimeter) mesh hardware clo 
to a frame of thin-wall electric tubing of %-inch (1.2 
centimeter) diameter. Each cage was 4.5 feet (1. 
meters) long, 4 feet (1.22 meters) deep, and 4 fe 
(1.22 meters) wide, and was floated by Styrofoa 
to provide a water depth of about 3 feet (0.9 mete 
and a water volume of about 2 cubic yards (1.5 cul 
meters). Thus stocking was at a rate of 400 catt 
per cubic yard (523 per cubic meter). Each ca 
was provided with a plywood cover having a “fee 
ing ring” in the center. The “ring” had rectangu! 
dimensions of 11.25 x 22.5 inches (28.6 x 57.15 cen 
meters) enclosing a water surface of 1.76 square fe 
(0.16 square meter), and extending about 16 incl 
(40.6 centimeters) below the water surface. T 
ring was designed to control the rate of feeding : 
tivity and to prevent the feeding fish from splashi 
the floating food out of the cage. Cage design 
shown in the cover photo. 
In earlier experiments (Buck et al. 1973) 
had fed both caged and uncaged catfish populatic 
a floating ration formulated as a supplemental fe 
for catfish free in ponds and found that this rat 
was inadequate for catfish that were confined 
cages, and resulted in high mortalities. In the pres 
experiments all feeding was with Purina trout che 
. 
COVER PHOTO: Illustration of catfish cage design with “feeding rings.” 
2 
