Unsustainable fishing practices directly impact the abundance of freshwater and marine life, their diversity, size and maturity as well as transforms the predator/prey food web. It threatens to deplete deep sea and coastal fishery stocks, reducing important predator species populations and other marine life including sea lions, turtles, dolphins, whales and birds thereby altering the composition of ecological communities. There are a number of destructive fishing methods that must be regulated or prohibited including blast, cyanide, driftnet, trawling, and dredging.

Recently, marine aquaculture operations have been rapidly expanding in fragile coastal habitats and threaten particularly sensitive ecosystems including wetlands, mangroves, estuaries, seagrass meadows, coral reefs and specific benthic species and/or communities with their waste, nutrients and antibiotics. The direct ecological impact on coastal and marine environments includes the physical alteration of coastlines (sediment mobilization and mangrove removal), disruption of vital marine ecosystem services, degradation or loss of natural habitats (wild spawning and nursery grounds), introduction of invasive species and loss of biodiversity.