A study by Haroon and Pittman (1997a) on the feeding of B. gonionotus in rice
fields also showed a high positive selectivity index of this species for macrophytes.
Haroon (1998) postulated that the species escapes intraspecific food competition in rice –
fish systems. However, our data suggest that food competition does limit the growth of B.
gonionotus in the rice field. While it cannot be denied that the rice biomass increases
throughout the rice crop, it is also important to note that rice plants grow taller while the
field floodwater remains at a level of approximately 15 cm.