Plastic straws account for 0.03 percent of global ocean pollution, while fishing nets account for 46% of global ocean pollution.

Because fish retain a high amount of ecosystem nutrients in their tissues, transport nutrients farther than other aquatic animals, and excrete nutrients in dissolved forms that are easily available to primary producers, fish play a key role in nutrient cycles.

Around intensive fish farms, waste from fish feed and faeces can pollute the water and seabed, resulting in poor water and sediment quality. Chemicals and pesticides (which are used in certain fish farming to manage parasites and disease) can potentially contaminate the environment and have an impact on nearby marine species.