Plastic pollution: a peril to our shores

Being both pliable and durable in nature, plastic has become one of the most used human-made products in the manufacturing industry. Yet when it comes to the existence of our marine life and the status of our shores, this synthetic substance is finding itself in the firing line. This year, Keep Australia Beautiful Week puts plastic in the spotlight. While marine litter is made up of an assortment of debris, it is plastic that is the major contributing factor, accounting for 80% of the items found along many stretches of Australian coastline.

Plastic debris can be categorised into two forms depending on its size: macroplastics and microplastics. Macroplastics include large, often single-use items, such as plastic bags, food packaging, plastic coffee cups, straws and drink bottles.

 Despite efforts to reduce usage, plastics still make up 80% of the debris found along our shores.  Image:  Jo Lanta  on  Unsplash

Despite efforts to reduce usage, plastics still make up 80% of the debris found along our shores. Image: Jo Lanta on Unsplash

As a substance, plastic of any kind is hard to completely eradicate and becomes impractical after its initial use. However, in terms of their slender size, straws in particular can easily fall through conveyer belts that are used in the recycling of waste products. Even if appropriate measures are taken for disposal, most end up as landfill or swirling into mouths of water drains and finally being deposited onto our shores.

While most of us are accustomed to the addition of a straw, whether to sip on a smoothie or indulge in a glass of iced tea or coffee, now consumers and some bars, pubs and cafes are starting to cause a stir, ditching the plastic accompaniment altogether. It is clear that banning and reducing straw consumption, along with other types of macroplastics, is starting to become a priority.

On the other end of the scale, microplastics - that is, any type of plastic that is 5mm or less in diameter - is also under scrutiny. Primary microplastics are a major nuisance to marine life, and include items such as resin pellets, also called ‘nurdles’ or ‘mermaid tears’, and microbeads found in shampoo, gels and other cosmetics. Secondary microplastics are those resulting from macroplastics that have been broken down into tiny particles. These are so minuscule that they can barely be seen with the naked eye.

Regions such as Port Phillip Bay are at serious risk of becoming pools of plastic pollution through stormwater run-off, which enters into systems such as the Yarra and Maribyrnong Rivers and finally into the Bay. While samples from both categories of plastic are present, along with recreational fishing nets and gear, it is the smaller form that is an emerging threat to our marine ecosystems.

 Port Phillip Bay and its inhabitants are at particular risk when it comes to plastic pollution.  Image: Cathy Cavallo

Port Phillip Bay and its inhabitants are at particular risk when it comes to plastic pollution. Image: Cathy Cavallo

Port Phillip Bay lends itself to over 1,000 species of marine plants and animals. It is a cosmos of activity, providing an abundance of food and habitat to a multitude of unique species. However, plastic pollution is resulting in much cause for concern, with the Bay's population of bottlenose dolphins at particular risk. Plastics that encroach on their environs can disrupt the balance of the food chain and cause blockages to the intestinal system. In marine habitats, plastics can also soak up toxins already found in the surrounding environment, leading to further issues for the unfortunate organism that may ingest them. 

While reducing the need for plastic is a simple act that many of us can introduce to our daily routines, the impact of doing so on a large scale allows our shores to be free from this form of debris that is a pest to the marine life present. In turn, this will hopefully better protect those species that call our seas and shores home.

For more information on Keep Australia Beautiful Week, see here. 


Priya Mohandoss reports for the Royal Society of Victoria and writes a column called “Environment Matters” for the Kinglake Ranges community news magazine, Mountain Monthly. She has recently completed a Masters of Media and Communications and is an avid explorer of all aspects of nature. 


Banner image courtesy of Danielle MacInnes on Unsplash.