Plastic has become a staple of modern day life. Its durability, versatility and relative cheapness makes it a near perfect material. Because of the many diverse applications of plastic, is impossible to speak simply of “plastic” in the environment. Different types and sizes of plastic have very different impacts. The term “marine debris” is equally as ambiguous. We could be discussing anything from lost shipping containers to bottle caps, derelict fishing nets to plastic bags.
Debris is often categorized by size, source, and/or type.The most obvious type of marine debris is marine litter. Marine litter is basically conventional litter that is in the ocean. It comes from land and is often caused by human carelessness and neglect. These include bottles, bags, cups, straws, utensils, etc. The most ubiquitous form of marine debris is microplastics. These are tiny (< 5mm) pieces of plastic that are suspended in the water column. Mostly they come from the degradation of larger plastic, but they can also be microbeads from personal care products or nurdles from plastic industry. Microfibers is a special type of microplastic. They are tiny threads that get into the environment from the breakdown of synthetic clothing in laundry machines. Another important catego
ry of marine debris is derelict fishing gear. These can be large nets lost at sea, fishing lines, or lost lobster pots.
The primary threat of large debris is entanglement. Lost nets continue to catch and kill marine animals as they drift through the oceans. Fishng line can become wrapped around fins and flippers making it difficult for the animal to
swim. As pieces of debris get smaller there is an increasing threat of ingestion. When animals eat plastic, it can choke them, cause internal damage, or produce a false sense of fullness that leads to eventual starvation. At even smaller sizes, plastics present threats on a cellular and toxicological level.
More than 700 marine species have been documented ingesting or entangled in plastic, but it is very likely at all ocean creatures are being impacted.
Stay tuned! Over the next few weeks I will be delving deeper into some of these major categories.