ML :

Here is what I have been trying to find (sort of) for you , another early xmas gift. See below which involved tilapia (blue). I assume no pratical difference. This was very hard to find . \:\) ewest

Effects of Cover and Prey Size on Preferences of Juvenile
Largemouth Bass for Blue Tilapias and Bluegills in Tanks !
HAROLD L. SCHRAMM, JR.
Department of Fisheries and Aquaculture
School of Forest Resources and Conservation
ALEXANDER V. ZALE
Florida Cooperative Fish and Wildlife Research Unit
School of Forest Resources and Conservation
University of Florida, Gainesville, Florida 32611

Abstract
The effects of vegetative cover and relative size of prey were tested on the forage preference of
juvenile largemouth bass Micropterus salmoides offered blue tilapias Tilapia aurea and bluegills
Lepomis macrochirus in laboratory electivity experiments. When offered forage at or near the
maximum consumable size in tanks without vegetative cover, largemouth bass preferred bluegills,
but consumed blue tilapias in the presence of vegetation. When offered forage smaller than the
maximum consumable size in tanks without vegetation, largemouth bass selected blue tilapias.
Differences between the forage species in body morphology and effective use of protective cover
apparently caused the changes in prey selection. Our results suggest blue tilapias may be a suitable
forage for largemouth bass, but that habitat characteristics and relative size distributions of other
available forage may affect their use.

Quote :

The increased consumption of blue tilapias by
largemouth bass in the vegetated tanks suggest
that blue tilapias did not use vegetative cover to
escape predation as effectively as bluegills.

However, our casual observations of blue
tilapias in aquaria indicate they are not as in-
clined to enter cover when frightened as bluegills.

Juvenile
largemouth bass selectively foraging on blue ti-
lapias when vegetation is present may further
reduce predation on bluegills. Shaftand et al.
(1983) found an increase in the abundance of
small bluegills in a vegetated lake containing
largemouth bass and an expanding population of
blue tilapias.

SHAFLAND, P. L., R. J. WATTENDORF, R. S. ANDERSON,
AND R. J. METZGER. 1983. Annual report for
non-native fish research 1982. Florida Game and
Fresh Water Fish Commission, Tallahassee, FL,
USA.