Drift Net Fishing
Fish are caught by nets that stretch for many miles on end. The nets hang somewhere between 30-50 ft and stretch 30-40 miles. This tactic of fishing can kill many unwanted species or bycatch like seaturtles, dolphins, sharks, etc. This method of fishing can easily overfish areas of the ocean because of its size and effectiveness of catching nearly everything near it including seals like in the picture to the left[5].
Aquaculture
Involves farming of fish either off the coast or in a building with pools. The issues with Aquaculture is that it has a large waste output which is usually disposed of in the ocean instead of using it as fertilizer. Due to the fact that most aquacultures are on the coast many mangrove forests and wetlands are at risk to habitat destruction. With the fish in a small area with a dense amount of waste and food diseases can spread quickly. Many antibiotics are used to temporarily counter the diseases like in industrial cattle farming. The issues with using Aquaculture is that it disposes a lot of dense waste directly into the ocean. Another issue is that it usually requires more grain and fish than the fish it produces. Aquaculture is considered unsustainable because of this[4].
Issues with overfishing Sterling