An estimated 8% of total aquatic primary production (137,000 Mt dry weight) is needed to sustain capture fisheries, seaweed collection and aquaculture; this proportion ranges from 2% in the
open ocean to 24±35% in freshwater, shelf and upwelling systems. Global capture fisheries (plus aquatic plants) remove 123 Mt fromthe sea and lakes, of which 27 Mt is directly discarded as bycatch