An empirical model relating food requirements to morphometric indices of metabolic
rate was used to calculate consumption/biomass ratios (Q/B) for 16 species of fish
that make the pelagic fish community in Lake Malawi/Niassa. The Q/B/year varied from
3.31 to 9.82, with the large catfish (Dinotopterus nyasensis) having the
lowest and a small cyprinid (Engraulicypris sardella) having the highest
Q/B ratio. Direct estimates of Q/B for four of the most abundant species, based on
analysis of diel feeding patterns, ranged from 4.20 to 24.70; the extreme values in
this range representing replicate studies on the same species, the predatory cichlid
Rhamphochromis longiceps. Previous studies that indicated exceptionally low
Q/B ratios (1.0) in pelagic cichlids from Lake Malawi are not supported by this
more recent work.