Overfishing, or catching fish faster than they can grow and reproduce, is a significant problem in all oceans. If unchecked, overfishing leads to smaller populations and smaller sized fish. Reduced catches results in fisherman making less or no money, negatively impacting the fishing community or town. Overfishing also greatly impacts the marine ecosystem, leading to reduced biodiversity (=less species) and poor ecosystem functioning because the fished-species may play an important ecological role such as providing food for other animals.
A scientific study published last week in the journal Science (Worm et al. “Rebuilding Global Fisheries) has found that fish populations can rebound, leading to greater profits and healthier ecosystems, through good fisheries management and conservation practices. Some management tools that can rebuild fish populations include gear restrictions, closed areas, and using catch shares where fishermen “own” the fishery. The appropriate tools vary between countries, with community co-management working well in developing countries like Kenya, while catch shares work better in developed countries like Iceland.
Commercial or industrialized fishing based on good management and science, and governments not waiting for fish populations to collapse before acting, has meant that some regions like Alaska and New Zealand have healthy marine ecosystems and high fish catches. If governments are slow to respond and overfishing continues unchecked, then any rebuilding will take significantly longer, possibly decades. One significant concern noted in the study was the impact of international fleets, particularly fishermen from developed countries fishing in the waters around Africa and competing with local African fishermen.
Conservation of our oceans and marine life is dependent on many factors from good fisheries management, effective governance, shared responsibility, and consumers making informed seafood choices.