The Biology and Culture of Tilapias

Littoral floor slope

Figure 5. Relationship between organic content, protein content, total amino acid con-
tent and assimilable amino acidlenergy ratios in the diet and slope of the littoral floor in
Lake Valencia, Venezuela. Adult S. mossambicus feed selectively in the steeply sloped
areas. (Reproduced by permission of the American Association for the Advancement of
Science.)

In view of the abundance of detrital energy and the limited availability of

protein-rich detrital food, both the Lake Sibaya and the Lake Valencia

populations provide excellent examples of the way in which "ecosystems

function to expend readily available energy to minimize the constraints

imposed by limiting nutrients" (Reichle et al. 1975).