Issues Affecting Marine Ecosystems Answers

Marine debris consists of most anything used and discarded by humans. Winds, rivers and storms can carry this debris to the ocean from far inland, so it is not solely a case of pollution along shorelines. It is also true that oceangoing ships directly contribute to marine debris while they are at sea and not associated with any particular nation.

Marine debris results from human garbage that makes its way to the ocean. A strategy to reduce, reuse, and recycle would generally reduce the amount of garbage produced by society with the additional effect of reducing the amount of garbage that becomes marine debris.

For some species of fish, bottom trawling is the most cost effective means of harvesting it. Additionally, as the populations of some fish decline their price goes up dramatically, making even a single catch extremely valuable.

While plastic is not generally considered biodegradable, it can be broken down by the action of photodegradation and certain microbes. The breakdown products of plastic, however, are extremely toxic to marine life and once the plastic breaks down they are free to enter into the food chain. Therefore, while plastic marine debris is hazardous and dangerous to marine organisms, the toxic breakdown products of plastics have the potential to do even more damage.

Seafood Watch identifies seafood that has been harvested in a sustainable manner and promotes this seafood over varieties that were not sustainably harvested. The idea is that only the fishermen utilizing sustainable practices are rewarded financially and will therefore outcompete their competitors. The theory goes that over a long period of time, only fishermen using sustainable practices will remain in business.

A reduce, reuse, and recycle policy can prevent marine debris by lowering the amount of disposable material people use, extending the life of products, and recovering materials instead of throwing them away. This means less waste is available to blow or wash into storm drains, rivers, and the ocean.

Bottom trawling continues because it can catch large quantities of seafood efficiently and generate profits to meet consumer demand. Fishing jobs and communities may depend on it, and rules or enforcement may not be strong enough to prevent the practice. These economic pressures can keep it in use even though it damages seafloor habitats and can produce substantial by-catch.

Seafood Watch provides recommendations about which seafood to buy or avoid based on how sustainably it is caught or farmed. These recommendations help consumers make responsible choices and encourage seafood businesses and fisheries to adopt practices that protect fish populations and marine habitats.

As plastic biodegrades or breaks apart, it can become tiny microplastics that are difficult to remove from water and sediments. Marine organisms may ingest these particles, and they can move through food webs. Breaking down plastic can also release chemicals or additives into the environment, spreading contamination more widely than larger pieces of debris.

Marine debris comes from land-based sources such as litter, stormwater runoff, and waste carried by rivers, as well as ocean activities such as fishing, shipping, and recreation. Wind and water currents transport debris over long distances, so waste can cross national boundaries and affect oceans and coastlines far from its original source. This makes marine debris a global problem requiring action from many places.