The Lessonia nigrescens fishery in northern Chile: how you harvest is more important than how much you harvest

In Chile, management of natural resources usually starts right before its imminent collapse or after evident declination. In the northern area of the country, the fishery of brown seaweeds has an enormous social, ecological, and economical importance. More than 11,000 people depend directly or indirectly on the collection and harvesting of this resource. Ecologically, kelps constitute areas for food, reproduction, and refuge for hundreds of invertebrates and fish species. Economically, landings up to 300,000 dry tons per year represent close to US $60 million for the industry. Until 2002, the Chilean brown seaweed fishery was mainly sustained by natural mortality, where plants cast ashore were collected by artisanal fishermen. Since then, three brown seaweed species of economic importance (, , and ) have been intensively harvested in coastal areas between 18A degrees and 32A degrees S. To manage kelp populations along the northern Chilean coast, regulations have been based on the principle how you harvest is more important than how much you harvest. This exploitation strategy has been adopted between fishermen, industries, governmental entities, and scientists. Since represents more than 70% of total brown seaweed landings, this study tests the effects of harvesting on the following population variables: (1) abundance, (2) distribution, (3) juvenile recruitment, (4) plant morphology, (5) frequency of reproductive plants, and (6) biodiversity of the macroinvertebrate community associated to kelp holdfasts. Our results show that, despite the enormous harvesting pressure on density and biomass, the associated macroinvertebrate richness has been maintained, due to normal plant growth and high recruitment all year round.