Therefore, modulating the effect of growth dilution, feeds of biochemically high quality potentially lead to considerable reductions of total MeHg concentrations in farm-raised fish, yet provide increased fish yields.
The floodplains of tropical rivers, with their extensive network of swamps, lagoons, lakes, and ponds, have great potential for increased fish yields through better and more efficient management using either capture or culture techniques, or a combination of both.
Benefits would be defined in terms of increased fish yield, provision of more employment or increased nutritional opportunities which are sustainable.
Trees would be replanted or conserved (Borneo's forest has more tree species per hectare than anywhere else); the forest would regenerate; some 10,000 people would benefit from "community development" projects such as one to increase fishing yields.
Milk yield and its proportion of protein were unaffected by fish oil intake, whereas the proportion of milk fat increased linearly (P<0.02) with increasing fish oil.
Releases of industrial, ship, and agricultural effluents in the river increased substantially, fish yields decreased, and toxic damage to marine organisms increased.
Higher stocking densities (up to 5 fish m−2) can increase net fish yields further.
Within a few years of its introduction, O. mossambicus was able to establish naturalized populations in a number of reservoirs, leading to steep increases in fish yields.
As fish yields go down, increased demands are put upon the land as some fishermen switch to arable farming, O'Reilly says.
Fish yield in intensive fish ponds may reach ca. 5 tons of fish per ha.
