Plastic Consumption: Marine Life's Unhealthy Diet

Marine animals are vulnerable to the effects of plastic pollution in the ocean. Plastic ingestion reduces the storage volume of the stomach, causing starvation. It is estimated that 60% of all seabird species have eaten pieces of plastic, with that number predicted to increase to 99% by 2050. Marine mammals, such as whales, dolphins, porpoises, and seals, are also affected by plastic entanglement and ingestion.

How plastic ingestion causes starvation

Marine animals are vulnerable to plastic ingestion, which can cause starvation. Plastic ingestion reduces the storage volume of the stomach, causing animals to starve. This is particularly common in seabirds, with an estimated 60% of all seabird species having eaten pieces of plastic. This number is predicted to increase to 99% by 2050. Dead seabirds are often found with stomachs full of plastic, reflecting the rapid increase in ocean plastic pollution over the past 40 years.

Marine mammals are also at risk of plastic ingestion, with large amounts of plastic debris found in the habitats of critically endangered Hawaiian monk seals, including in areas that serve as pup nurseries. In 2019, a whale was found washed up with 40kg of plastic in its stomach, mainly plastic bags. Another whale died from an inflammation of its abdominal tissues caused by the presence of nearly 30kg of indigestible plastic, including shopping bags, fishing nets and a jerry can.

Fish in the North Pacific ingest 12,000 to 24,000 tons of plastic each year, which can cause intestinal injury and death, and transfer plastic up the food chain to bigger fish, marine mammals and human seafood eaters. A recent study found that a quarter of fish at markets in California contained plastic in their guts, mostly in the form of plastic microfibers.

Sea turtles often mistake floating plastic garbage for food, which can lead to choking, internal injury and death. They can also starve by thinking they are full after eating plastic. All seven sea turtle species are affected by plastic pollution.

The characteristics of plastic debris, such as colour, size and shape, can attract certain types of wildlife. Animals that filter water to consume their food, such as baleen whales, mussels and oysters, can easily ingest microplastics, or plastic pieces smaller than 5 mm. Other animals, such as birds, fish, turtles and toothed whales, may accidentally ingest plastic marine debris while eating their prey, which may have also eaten plastic.

How plastic entanglement causes injury and death

Marine animals are vulnerable to plastic entanglement, particularly from ghost fishing gear. Ghost gear refers to fishing ropes, nets and pots that have been discarded or abandoned at sea and are often made from plastic. This can trap and entangle a variety of marine life, from large marine mammals like blue whales to small crabs. An estimated 300,000 whales, dolphins and porpoises die from ghost gear entanglement every year.

Plastic entanglement can lead to injury and death. For example, entanglement in plastic debris has led to injury and mortality in the endangered Steller sea lion, with packing bands being the most common entangling material. Marine animals can also get trapped in plastic rings, which can cut off circulation and cause infection.

Large pieces of plastic can also block the digestive tracts of marine animals, causing starvation. In 2019, a whale was found washed up with 40kg of plastic in its stomach, including shopping bags, fishing nets and a jerry can. This caused an inflammation of its abdominal tissues, leading to its death.

Plastic debris can also attract certain types of wildlife due to its colour, size or shape. Animals that filter water to consume their food, such as baleen whales, mussels and oysters, can easily eat plastic, most commonly in the form of microplastics (plastic pieces smaller than 5 mm). Other animals, such as birds, fish, turtles and toothed whales, may accidentally ingest plastic marine debris while eating their prey, which may have also eaten plastic.

How plastic debris attracts certain types of wildlife

Marine animals are attracted to plastic debris due to its characteristics, such as colour, size and shape. The amount of debris in a certain area and the feeding behaviours of different animals also play a role in which animals are more likely to eat it. Some animals filter water to consume their food, such as baleen whales, mussels and oysters, and can easily eat plastic, most commonly in the form of microplastics, or plastic pieces smaller than 5 mm. Other animals, such as birds, fish, turtles and toothed whales, actively search for and capture their food and may accidentally ingest plastic marine debris while eating their prey, which may have also eaten plastic.

Sea turtles often mistake floating plastic garbage for food, which can cause choking, internal injury and death, or starvation by thinking they are full from eating plastic. Similarly, a recent study found that a quarter of fish at markets in California contained plastic in their guts, mostly in the form of plastic microfibers.

Large marine mammals are also highly vulnerable to plastic entanglement, particularly from ghost fishing gear. Fishing ropes, nets and pots that have been discarded or abandoned at sea are often made from plastic and can trap and entangle a variety of marine life, from blue whales to small crabs. An estimated 300,000 whales, dolphins and porpoises a year die from ghost gear entanglement.

It is estimated that 60% of all seabird species have eaten pieces of plastic, with that number predicted to increase to 99% by 2050. Dead seabirds are often found with stomachs full of plastic, reflecting how the amount of garbage in our oceans has rapidly increased in the past 40 years.

How plastic transfers up the food chain

Marine animals are vulnerable to plastic ingestion and entanglement. It is estimated that 60% of all seabird species have eaten plastic, with that number predicted to increase to 99% by 2050. Dead seabirds are often found with stomachs full of plastic, which reduces the storage volume of their stomachs, causing starvation.

Fish in the North Pacific ingest 12,000 to 24,000 tons of plastic each year, which can cause intestinal injury and death. This plastic is then transferred up the food chain to bigger fish, marine mammals and human seafood eaters. A recent study found that a quarter of fish at markets in California contained plastic in their guts, mostly in the form of plastic microfibers.

Some animals filter water to consume their food, such as baleen whales, mussels and oysters, and can easily eat plastic, most commonly in the form of microplastics, or plastic pieces smaller than 5 mm. Other animals, such as birds, fish, turtles, and toothed whales, actively search for and capture their food and may accidentally ingest plastic marine debris while eating their prey, which may have also eaten plastic.

Marine megafauna are also vulnerable to plastic ingestion. In 2019, one whale was found washed up with 40 kg of plastic in its stomach, mostly comprising plastic bags. Another sperm whale died from an inflammation of its abdominal tissues caused by the presence of nearly 30 kg of indigestible plastic, including shopping bags, fishing nets and a jerry can.

How plastic pollution kills marine mammals

Marine mammals are vulnerable to the effects of plastic pollution in the ocean. Large marine mammals are at risk of plastic entanglement, particularly from ghost fishing gear. Ghost gear is discarded or abandoned fishing ropes, nets and pots that are often made from plastic. This type of plastic pollution traps and entangles a variety of marine life, from blue whales to small crabs. An estimated 300,000 whales, dolphins and porpoises die each year from ghost gear entanglement.

Marine megafauna are also vulnerable to plastic ingestion. Plastic ingestion reduces the storage volume of the stomach, causing starvation. In 2019, a whale was found washed up with 40kg of plastic in its stomach, mainly plastic bags. Another whale died from an inflammation of its abdominal tissues caused by the presence of 30kg of indigestible plastic, including shopping bags, fishing nets and a jerry can.

Plastic pollution can also cause intestinal injury and death, and transfers plastic up the food chain to bigger fish, marine mammals and human seafood eaters. A recent study found that a quarter of fish at markets in California contained plastic in their guts, mostly in the form of plastic microfibers.

The characteristics of plastic debris, such as colour, size or shape, can attract certain types of wildlife. The amount of marine debris in a certain area and the feeding behaviours of different animals can play a large role in which animals are more likely to eat marine debris. Some animals filter water to consume their food (e.g. baleen whales, mussels, oysters) and can easily eat plastic, most commonly in the form of microplastics, or plastic pieces smaller than 5mm. Other animals (e.g. birds, fish, turtles, toothed whales) actively search for and capture their food and may accidentally ingest plastic marine debris while eating their prey, which may have also eaten plastic.

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