The Impact Of Plastic Pollution On Seals' Health And Habitat

Seals are intelligent, strong, and top predators, yet they are suffering from human acts and wastefulness. Plastic pollution is having a devastating impact on seals, with microplastics, abandoned fishing gear, and other plastic waste threatening their lives and health. Seals can become entangled in plastic waste, leading to gruesome deaths, and they also ingest microplastics, which can cause toxic chemical buildup, increase the chance of disease, and affect reproduction. With billions of pounds of plastic in our oceans and more being added each year, it is essential to address this global crisis and protect seal populations from the harmful effects of plastic pollution.

Seals eat plastic, mistaking it for food

Seals are curious and playful creatures that often end up playing with plastic rubbish and ocean pollution, such as fishing lines, nets, packing straps, and plastic bags. While their inquisitive nature puts them at risk of entanglement, it also leads them to ingest plastic, mistaking it for food.

Seals are not directly consuming plastics; instead, they are eating fish that have ingested plastic after it has been broken down into smaller pieces by rocks and waves. This was evidenced by a study conducted between 1990 and 1997, where researchers examined the droppings of two species of Antarctic fur seals and found plastic chunks, indicating that the seals had consumed plastic-eating fish.

The plastic consumed by seals often comes from discarded plastic containers that have degraded into smaller pieces, known as microplastics. These microplastics are a significant concern as they are more likely to be ingested by seals and other marine animals due to their small size. Furthermore, plastic contains toxic chemicals that can increase the chance of disease and affect reproduction, causing seals to suffer for months or even years before they eventually die.

The issue of plastic pollution in the oceans is not limited to a specific location but is widespread, affecting even remote places. It is a pressing environmental concern, with an estimated 15 to 51 trillion microplastic particles floating in the world's oceans, weighing between 93,000 and 236,000 tonnes. This crisis is only expected to worsen, with predictions that plastic will outweigh all the fish in the sea by 2050 if current trends continue.

Plastic ingestion can cause intestinal injury and death

Marine plastic debris is one of the most pressing environmental concerns facing the world today. Seals, curious and playful by nature, often end up playing with plastic rubbish and ocean pollution, such as fishing lines, nets, packing straps, and plastic bags. This plastic waste can cause severe harm to seals, including intestinal injury and death.

Plastic ingestion can cause intestinal blockage, leading to serious health complications and even death. Sharp or rough plastic debris can puncture the stomach lining, causing internal bleeding and infection. It can also block the pyloric sphincter, the part of the stomach that empties into the intestines, resulting in inflammation and preventing the animal from digesting food. This blockage can lead to a reduced urge to eat, malnutrition, and, ultimately, starvation.

The ingested plastic may also carry harmful pollutants or release chemicals added during production, which can further endanger the health of seals. These toxins can affect reproduction and increase the chance of disease. Seals may suffer for months or years after ingesting plastic before eventually succumbing to their injuries or illnesses.

The impact of plastic pollution on seals highlights the urgent need to address this global crisis. It is essential to reduce plastic waste, improve waste management practices, and protect marine life from the deadly effects of plastic pollution. By working together, we can mitigate the harmful consequences of plastic ingestion on seals and other marine animals.

Plastic waste can tighten around a seal's neck, flipper or mouth, leading to a slow death

Seals are naturally playful and curious creatures. Unfortunately, this makes them particularly vulnerable to the dangers of plastic pollution in the ocean. Plastic waste, such as fishing lines, nets, packing straps, and plastic bags, can entangle seals, leading to devastating consequences. Once a seal is entangled, it cannot free itself. As the seal grows, the plastic waste tightens around its neck, flipper, or mouth, resulting in a slow and gruesome death. This issue is prevalent on the Western Cape coastline, where a thriving fishing industry and a large population of Cape Fur Seals compete for the same fish.

The Hout Bay Seal Rescue Centre in South Africa has witnessed the heartbreaking consequences of seal entanglement first-hand. They receive calls about seals in distress at all hours of the day and night and work tirelessly to rescue and rehabilitate them. The centre also collaborates with local organizations like the Cape Town Bucket List Ocean Adventures (CTBL) Group, which regularly conducts harbour clean-ups to mitigate plastic pollution in the area. Despite these efforts, the ongoing influx of plastic waste into the ocean perpetuates the problem.

The entanglement in plastic waste not only causes physical suffering but also has broader ecological implications. Seals are apex predators in their ecosystem, occupying the top of the food chain. When they ingest microplastics or become entangled, it not just leads to their suffering and death but also impacts the health of the entire marine environment. Seals are considered a sentinel species, indicating the health of the marine ecosystem. If the seals are sick, it is a sign that our oceans are sick as well.

The impact of plastic pollution on seals highlights the urgent need for sustainable solutions. While organizations like the Hout Bay Seal Rescue Centre and the Global Ghost Gear Initiative (GGGI) are doing invaluable work, addressing the root of the problem is essential. This includes advocating for corporations to stop producing single-use plastics and promoting reusable alternatives. Additionally, holding industries accountable for their negligent behaviour and working with governments to protect marine life is crucial.

The suffering and death of seals due to plastic waste tightening around their bodies is a grim reminder of the urgent need to address plastic pollution. It is our responsibility to protect these magnificent creatures and ensure the health of our oceans for future generations.

Plastic contains toxic chemicals, which can affect reproduction and cause disease

Seals are dying due to plastic pollution. Plastic waste is littering our oceans and threatening the lives of millions of marine animals. Seals often ingest microplastics, tiny pieces of plastic that come from larger plastics that have degraded over time. These microplastics contain toxic chemicals, which can affect the health of seals in various ways.

Firstly, plastic contains toxic chemicals, which can affect reproduction and cause disease. Seals, being apex predators, feed on fish, which in turn feed on plankton. Plankton, being primary producers, can easily confuse microplastics for their food source and consume them. This process is known as trophic transfer, and it allows microplastics to move up the food chain from plankton to fish to seals. While the digestive system of seals can successfully excrete these microplastics, the toxins that latch onto the plastic particles can enter the body and cause harm. These toxins can cause endocrine disruption and alterations to the immune system. In seals, exposure to these toxins can lead to physical abnormalities, impair the development of motor activities and cognition, cause behavioural changes, and impair reproduction.

Furthermore, the thick layers of blubber in seals can absorb and retain pollutants from industrial waterways. A study showed that harbour seals in South Puget Sound were significantly more contaminated than those in Canada's Georgia Strait. Seals are considered a sentinel species, indicating the health of the marine environment. The high levels of contamination found in seals can also be passed on to their offspring through their milk.

The issue of plastic pollution is not limited to the ocean but also extends to land-based pollution, such as plastic blown into the sea from littered beaches or washed into the sea by stormwater. Seals can also directly ingest plastic rubbish and ocean pollution, such as plastic bags and packing straps, out of curiosity or playfulness. Once entangled in plastic waste, seals may suffer a slow and painful death as the plastic tightens around their body as they grow.

Plastic polymers attract PCBs and other toxic chemicals, creating hormonal imbalances in seals

Seals are highly affected by plastic pollution. They ingest microplastics and suffer the consequences of plastic entanglement. Plastic polymers attract PCBs and other toxic chemicals, creating hormonal imbalances in seals.

Polychlorinated biphenyls (PCBs) are highly toxic chemical compounds that were once widely used in the manufacture of carbonless copy paper, heat transfer fluids, and dielectric and coolant fluids for electrical equipment. Despite being banned internationally in 2001, PCBs continue to be inadvertently produced and persist in the environment due to their longevity. They are known to cause endocrine disruption, neurotoxicity, and other harmful effects in humans and animals.

Seals, as sentinel species, are particularly vulnerable to the toxic effects of PCBs and other pollutants in the marine environment. Their thick layers of blubber absorb and retain these pollutants, leading to health issues such as physical abnormalities, behavioral changes, impaired reproduction, and immune disorders. The contamination of seals with PCBs has been linked to reproductive failure, skull deformations, bone lesions, and improper immune function in various seal species.

Plastic polymers act as a magnet for PCBs and other toxic chemicals. When ingested by seals, these pollutants create hormonal imbalances and affect reproductive abilities and brain activity. The presence of PCBs in the marine environment, facilitated by plastic pollution, poses a significant threat to the health and survival of seal populations.

The accumulation of plastic waste in the oceans is a pressing issue that requires urgent attention. The harmful effects of plastic pollution on seals and other marine life underscore the need for sustainable solutions to address this global crisis.

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