Final answer:
Coastal fisheries primarily exploit the rich waters of the continental shelves, which are highly productive marine areas. However, overexploitation has caused dramatic declines in fish populations and marine biodiversity, raising the need for sustainable fisheries management.
Step-by-step explanation:
An estimated 95% of the world's major fisheries are located in coastal waters. These coastal fisheries exploit the rich waters of the continental shelves, which are underwater landmasses extending from a continent that result in relatively shallow waters compared to the open ocean depths. The continental shelves are areas of high productivity due to factors such as sunlight reaching the seabed, which allows for photosynthesis, and nutrient upwelling from ocean currents. Together, these conditions support abundant marine life and make these zones particularly valuable for fishing industries.
Despite the abundance, overexploitation has led to significant declines in fish populations. According to the FAO, 52% of marine stocks were fully exploited and 24% were overexploited or depleted, signaling a crisis in marine fisheries sustainability. Industrial and small-scale fisheries have been extracting an immense quantity of marine resources, causing severe declines in species like the Brazilian sardine and various gadids, including cod. Overexploitation not only leads to reduced populations but also to decreased marine biodiversity and impaired ecosystem services.
As such, conservation and sustainable management of these fisheries are crucial. Balancing the socioeconomic needs of communities relying on fishing with the preservation of maritime ecology is a significant global challenge.