Microfibres: What Do They Mean for Fish and Fishing?
Hannah Rudd is the Policy & Advocacy Manager for the Angling Trust where she fights for the future of fish and fishing. Hannah also works with recreational anglers in England, gathering data on UK shark species through the collaborative group Shark Hub UK. 
As a marine scientist and author with a passion for protecting our waters and the wildlife that live in them, we're very pleased to welcome Hannah as a guest on our blog, where she speaks about plastic pollution:

Plastic. It’s the environmental buzzword on everyone’s lips. Wreaking havoc in our rivers, lakes, estuaries, and seas, it comes in many forms. Often people imagine plastic pollution to be large debris like bags, straws, and bottles that dominate our landscape. In fact, it is a much teenier version that is causing a huge environmental catastrophe. Plastics that are only a few millimetres in diameter – termed microplastics and microfibres - accumulate in microscopic organisms and rise up the food chain. They are devastating our aquatic life, but their consequences are often invisible until it’s too late. So, how do these tiny pieces of plastic impact fish and fishing, and what exactly are they?

What are microplastics?

Microplastics are plastic fragments five millimetres or less in diameter. Some microplastics have been manufactured intentionally, such as microbeads for beauty products, whereas others are created by the degradation of large plastic products.

Plastic doesn’t break down naturally. Instead, it photodegrades - meaning it deteriorates under sunlight – and as a result, it dries out, becomes brittle and breaks into subsequently tinier fragments. Over time, even microplastics degrade into dust-like particles known as nano plastics. Once microplastics enter the environment, they can be impossible to remove.

What are microfibres?

As the name suggests, microfibres are tiny synthetic strands of fibres from artificial materials like clothing. These synthetic materials are unknown to the natural environment, so microbes and other creatures have not evolved to deal with them.

Fibres from synthetic fabrics, such as acrylic and polyester, are shed in huge numbers during washing, about 700,000 per wash cycle, with the “delicates” wash cycle actually being worse than standard cycles. An estimated 68 million loads of washing are done every week in the UK, highlighting the severity of the problem. Billions of microfibres enter our waterways every day as surplus wastewater is ejected into our rivers.


Why is this bad for fish?

Microplastics and microfibres enter our environment in two ways – run-off from land-based sources like landfills, and wastewater overflow.

Once in our water-based ecosystems, tiny aquatic organisms can misidentify them as food and eat them. Plankton, a hugely important food source for aquatic organisms, is at the base of the food chain, so any harm done to this species will accumulate up to larger species. These harms include decreased ability to feed and reproduce, therefore ingestion of microplastics can have enormous repercussions on the health of an ecosystem. This is scientifically proven too. Zooplankton laced with microplastics in a lab had reduced nutrition and poorer health than those who did not have microplastics in their systems.

 Fish may also mistake microplastics for food, as well as predating on other organisms that have ingested microplastics. This is also the case for microfibres. When fish eat the plastic fibres, the plastic fills their stomach and gets stuck there. They feel full even though they only have plastic in their stomachs and in some rare cases they eventually starve to death.

Microplastic can also affect the fish at a cellular level, causing cell damage and inflammation, leading to reduced reproductive success and an inability to forage effectively. It’s early days so researchers are finding out more about the effects of microplastics and microfibres on fish and ecosystem health all the time – but it overall doesn’t look good.

What about humans?

The human health effects aren’t entirely clear either. A recent report found the average person ingests more than 5,800 particles of synthetic debris each year – and plastic fibres have been found by researchers in food, drinks and even in the Arctic. Plastic is everywhere. By 2050 the global production of synthetics is expected to triple.

 Our trajectory toward a plastic-free future looked promising before the global pandemic, but since then, our waterways have been filled with single-used PPE. It’s important to remember, though – it’s not plastic that’s the enemy. Plastic is vital for medical advancement, food safety and hygiene; the real enemy is how we dispose of it.

How can I help?

  • Buy tackle and other products with plastic free packaging