Bycatch – the catching and discarding of marine species that are not intended to be caught – in the ocean is a huge problem that is drastically affecting the fish and marine mammal populations within the ocean. A study done a few years ago found that approximately 1.5 tons of fish are discarded every night by shrimp trawlers in Australia alone. This is a result of the high demand for certain fish species by consumers and the large amount of money that fisherman can make out of this industry.These fishermen use techniques to capture as many fish as possible and these techniques are particularly harmful, often resulting in the capture of non-target fish species. Fishermen often discard these fish as it is often illegal to sell them.But the problem is that the fish, accidentally caught, are often dead when discarded into the ocean.These fishing techniques can often result in the complete destruction of the habitats of many fish.If you go to a local fishing boat when they are pulling in their nets, like the fishermen on Fish Hoek beach, you can often see rays, small dolphins and a large variety of other marine organisms in their nets along with their intended catch.This is just a local example of an international problem, and there are much larger vessels being used in the ocean in comparison to the one that we see on Fish Hoek beach.Due to the vulnerability of certain fish populations in the ocean, bycatch can possibly deliver the final blow to many different susceptible fish populations. Even if government issues quotas for vulnerable fish, this is not dealing with the problem of bycatch. A method to combat this has already been introduced in trawl nets, which acts as an escape pathway. This allows certain marine mammals and larger fish to pass through and escape the net before it is brought to the surface. This has already had a positive impact on the populations of many marine animals such as sharks and dolphins. But not all non-target fish are able to escape through these pathways.We need to seriously look into developing techniques that can reduce the amount of bycatch that takes place within the ocean.We also need to, as a community, consume fish that are captured using non-harmful fishing techniques. Otherwise, certain marine life that we cherish may not be around for the future generations to see. They may be reduced to looking at these fish in aquariums or in books. This column was contributed by Michael Hart-Davis, a student of Marine Science. Email him on email@example.com.