Plastic's Deadly Impact On Wildlife: Counting Casualties

Plastic pollution is a pressing issue that poses a significant threat to wildlife, both in the sea and along the shore. It is estimated that approximately 100,000 marine animals die each year from ingesting or becoming entangled in plastic, with millions of seabird deaths also occurring annually. The problem extends to a wide range of species, including seabirds, whales, dolphins, seals, sea turtles, and fish. The impact of plastic pollution on wildlife is not limited to direct fatalities, as it also causes intestinal injuries, starvation, and disrupted eating patterns. Furthermore, plastic waste can encourage the growth of pathogens and increase the likelihood of disease in organisms such as corals. The presence of microplastics in the environment has far-reaching consequences, affecting even microscopic animals and humans who ingest these particles unknowingly.

Marine mammals, including whales, dolphins, seals, and sea lions, die from ingesting plastic or getting entangled in it

Marine mammals, including whales, dolphins, seals, and sea lions, are extremely vulnerable to the dangers of plastic pollution. Whales, for instance, are harmed by both plastic debris and microplastics, with one stranded whale found to have ingested 135 items, mainly plastic bags, which can resemble squid, their natural prey. In 2018, a juvenile sperm whale was found dead on a Spanish beach with 30kg of plastic in its digestive tract, causing fatal inflammation.

Dolphins, too, are at risk from plastic pollution, with an estimated 300,000 dolphins, whales, and porpoises becoming entangled in nets and lines annually, leading to slow and painful deaths. Additionally, dolphins are susceptible to ingesting plastic, mistaking it for prey, as their sonar systems have not adapted to differentiate plastic from their prey.

Seals are also affected by plastic pollution, with a harp seal pup found dead in Scotland in 2018 with a piece of plastic clogging its intestines. While plastic ingestion in seals is rare, they often become entangled in fishing nets, lines, and lures, which can be fatal.

Sea lions, like seals, frequently become entangled in ocean debris, such as fishing equipment, plastic bags, and packing bands. They also ingest plastic, mistaking it for food, which can puncture their stomach lining and lead to death.

The impact of plastic pollution on these marine mammals highlights the urgent need for a global response to address and reduce plastic waste entering our oceans.

Abandoned fishing gear made from plastic entangles and kills hundreds of thousands of cetaceans

Plastic pollution is wreaking havoc on marine animals, killing or crippling them. Scientific reports have shown that plastic ingestion quickly becomes disruptive and poisonous, causing intestinal injury and death. It also transfers plastic up the food chain to bigger fish, marine mammals, and humans.

One of the most significant contributors to this crisis is abandoned fishing gear made from plastic, which entangles and kills hundreds of thousands of cetaceans. Also known as "ghost gear," this abandoned fishing equipment includes gillnets, traps, pots, or fish aggregation devices. It is considered abandoned when a fisher cannot retrieve it, often because it has become snagged on reefs, rocks, or other obstructions.

The impact of abandoned fishing gear on cetaceans, which include whales and dolphins, is devastating. These intelligent and socially complex creatures can suffer prolonged entanglement, resulting in physical injuries, physiological stress, and even death. The multi-million-year-old sonar system of whales and dolphins, which they use to navigate and find prey, has not had time to adjust to the relatively new presence of plastic in their environment. As a result, they are at an increased risk of becoming entangled in ghost gear.

The problem is exacerbated by illegal, unreported, and unregulated (IUU) fishing activities, as illegal fishers often abandon or discard fishing gear to conceal their operations. This has led to a situation where ghost gear is responsible for harming 66% of marine mammal species, including critically endangered species like the vaquita porpoise, driving them to the brink of extinction.

The WWF has been advocating for global action to address this issue, urging governments to support the establishment of a treaty to combat marine plastic pollution and encouraging countries to join the Global Ghost Gear Initiative (GGGI). The GGGI is a global alliance working to solve the problem of lost and abandoned fishing gear through collaboration between various sectors and industries.

Seabirds ingest plastic, which blocks their intestinal tracts and causes death

Plastic pollution is wreaking havoc on marine life, killing or crippling hundreds of thousands of animals. Scientific reports have shown that plastic ingestion quickly becomes disruptive and poisonous, causing eating pattern disruptions in marine wildlife.

Seabirds are among the worst affected by plastic pollution. It has been estimated that plastic ingestion causes the death of about 1 million seabirds annually. This number is predicted to increase as plastic pollution in the oceans continues to rise.

Seabirds are particularly vulnerable to plastic ingestion due to their feeding habits. They often mistake plastic debris for prey, and some types of plastic can resemble natural materials found on the sea surface. For example, Styrofoam and other spongy plastics have similar peck marks to cuttlebones in the North Sea. As a result, necropsies of dead seabirds have revealed that ingested plastic items can cause serious ulcerations in the gizzard or block the pylorus, making feeding impossible and leading to death.

In addition to the physical blockage caused by ingested plastic, toxins released from the plastic can also cause pathogenic illness in seabirds. This condition, known as "plasticosis", was first identified in flesh-footed shearwaters and has since been observed in other seabird species. The more plastic a seabird ingests, the higher the concentrations of toxins in their system.

The impact of plastic ingestion on seabirds is not limited to immediate deaths. Studies have shown that plastic ingestion can also cause chronic effects, including changes in behaviour, loss of body weight, reduced feeding rates, and decreased ability to produce offspring. These subtler, sublethal effects may have far-reaching consequences for seabird populations and the marine ecosystem as a whole.

Plastic waste encourages the growth of pathogens in the ocean, increasing the likelihood of corals contracting diseases

Plastic waste is a pressing issue that poses a significant threat to marine wildlife and ecosystems. One of the many detrimental impacts of plastic pollution is its role in encouraging the growth of pathogens in the ocean, which increases the likelihood of corals contracting diseases. This issue has been observed in coral reefs across the Asia-Pacific region, where billions of plastic items are entangled, posing a risk to one of the most biodiverse ecosystems on the planet.

Coral reefs provide vital fisheries and coastal defense, and plastic waste entanglement exacerbates the risk of coral disease outbreaks, leading to severe consequences. The presence of plastic waste stresses coral through light deprivation, toxin release, and anoxia, creating an ideal environment for pathogens to invade. The likelihood of disease increases drastically when corals are in contact with plastic, jumping from 4% to 89%. This increase in disease susceptibility is particularly prominent in structurally complex corals, which are eight times more likely to be affected by plastic.

The impact of plastic waste on coral health is not limited to physical entanglement. Plastic debris can promote microbial colonization by pathogens, providing a foothold for these disease-causing organisms to invade the coral. Microbial communities colonizing plastic waste have been found to be dominated by pathogenic bacteria, such as the genus Vibrio, which is implicated in white syndromes, a group of globally devastating coral diseases. The presence of these pathogens on plastic waste further increases the risk of disease outbreaks in coral reefs.

The consequences of coral disease outbreaks extend beyond the coral themselves. Coral reefs are home to a diverse array of marine life, and disease outbreaks can have cascading effects on the entire ecosystem. Additionally, the loss of coral reefs can have significant economic impacts, jeopardizing the billions of dollars in goods and services that coral reefs provide through fisheries, tourism, and coastal protection. Therefore, effective plastic waste management is critical to protecting not only the health of coral reefs but also the livelihoods of the people who depend on these ecosystems.

The issue of plastic waste and its impact on coral health is a pressing concern that requires urgent attention. With the weight of ocean plastics projected to exceed the combined weight of all the fish in the seas by 2050, the need for action is more urgent than ever. By addressing plastic pollution at its source and implementing better waste management practices, we can help reduce the threat to coral reefs and other marine ecosystems, ensuring their protection for future generations.

Microplastics are replacing zooplankton, reducing their capacity to process carbon and contributing to a loss of global oxygen

Plastic pollution is a pressing issue that poses a grave threat to wildlife, with thousands of animals, from small finches to blue whales, succumbing to painful deaths from ingesting and getting entangled in plastic. The insidious reach of plastic pollution extends beyond what meets the eye, as microplastics, nearly invisible pieces of broken-down plastics, pervade the marine environment. These microplastics are inadvertently consumed by zooplankton, tiny organisms that play a pivotal role in the marine ecosystem.

Zooplankton, a crucial food source for many secondary consumers, are inadvertently ingesting microplastics due to their ubiquitous presence in the marine environment. Research has confirmed the ingestion of microplastics by 39 zooplankton species from 28 taxonomic orders, encompassing both holo- and meroplanktonic varieties. This contamination of zooplankton has far-reaching ecological implications, as it introduces microplastics into the food web, potentially transferring them up the trophic levels to other marine organisms.

The negative consequences of microplastic ingestion by zooplankton are twofold. Firstly, it reduces their capacity to process carbon. Zooplankton, satiated by consuming microplastics, ingest less food, which can lead to increased algal blooms due to reduced feeding pressure. This alteration in the balance of algae and zooplankton disrupts the oxygen content of the oceans, contributing to a loss of oxygen beyond what is caused by global warming alone.

Secondly, the introduction of microplastics into the zooplankton population has broader implications for the marine food web. As zooplankton are a foundational food source for many secondary consumers, the contamination of zooplankton with microplastics facilitates the entry of these foreign particles into the diets of other marine organisms. This transfer of microplastics up the trophic levels exacerbates the issue of plastic pollution, affecting a diverse array of marine life.

The intricate interplay between microplastics and zooplankton underscores the complex and detrimental effects of plastic pollution on the marine ecosystem. While the full scope of these effects remains to be elucidated, the available research highlights the urgent need to address plastic pollution and mitigate its impact on the delicate balance of marine life. Recognizing the role of microplastics in disrupting the capacity of zooplankton to process carbon and maintain oxygen levels in the oceans is a crucial step toward preserving the health and sustainability of our marine environments.

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