from the catfish. It seems reasonable to expect that a tech- 
nique could be developed whereby the shiners could be 
trapped, baited, or otherwise removed with a minimum of 
contact with the companion species. If not, it would be 
important to assure that the catfish be enough larger than 
the shiners to permit their separation by mechanical grad- 
ing. Martin (1968) has suggested that the crop of fingerling 
catfish not exceed 10,000 per acre to assure that they will 
grow large enough to be easily separated from the shiners. 
LITERATURE CITED 
Martin, JAMES Mayo. 1968. The combined culture of catfish and min- 
nows as compared to monospecies culture. Commercial Bait Fish Con- 
ference Proceedings, Texas A & M University, College Station, Tex- 
as, March 19-20, 1968. 
Yasuouv, A. 1969. Mixed fish culture in ponds and the role of tilapia in 
it. Bamidgeh 21(3):75-92. 
For information on other Survey publications, address correspondence 
:;to George Sprugel, Jr., Chief, Illinois Natural History Survey, 
Natural Resources Building, Urbana, Illinois 61801 
Printed by the Authority of the State of Illinois 
oe, 
(38996 4M—4-72) 
12 
