Pollution's Impact: Count Of Animals Affected Yearly

Animals are extremely vulnerable to harm from pollution. Pollution comes in many forms, including air pollution, water pollution, and plastic pollution, and it can have devastating effects on a wide variety of creatures. It is estimated that every year, plastic kills 1 million seabirds and 100,000 sea mammals, turtles, and fish. Plastic is ingested by animals or they get entangled in it, and it can take hundreds of years to break down. Air pollution, such as smog, particulate matter, and ground-level ozone, can harm animals' lungs and cardiovascular systems. Water pollution, such as excess nutrients and harmful algal blooms, can create dead zones in the water, killing fish and other organisms. Pollution is a major threat to the survival of many species and it is important to address its impact on animals.

Plastic waste kills and harms marine life, including turtles, whales, and sharks

Marine life is suffering from the impact of plastic pollution. Plastic waste kills and harms marine animals, including turtles, whales, and sharks.

Sharks and rays are at high risk of entanglement in plastic pollution. A study published in the journal Endangered Species Reports found over 1,000 documented instances of sharks and rays becoming tangled in plastic debris. The actual number is likely much higher, as the study only included scientific journal articles and Twitter mentions. This entanglement can lead to scoliosis of the back, as seen in a mako shark entangled by a fishing rope in the Pacific Ocean. In another case, a sandbar shark was slowly being cut in half by plastic packaging twine. While this shark was rescued, many others are not so lucky, facing slow and painful deaths due to plastic entanglement.

Whales are also severely affected by plastic pollution. They ingest plastic, mistaking it for food, which can cause internal injuries and even death. A stranded whale was found to have ingested 135 items, mostly plastic bags, which can resemble squid, a whale's natural prey. Plastic debris also entangles whales, leading to a slow and agonizing death. About 10% of ocean plastic pollution is made up of plastic fishing nets and ropes, which ensnare approximately 300,000 whales, dolphins, and porpoises annually.

Sea turtles are particularly vulnerable to the effects of consuming marine debris. Plastic bags and fishing lines can become trapped in their stomachs, preventing them from swallowing food. This ingestion of plastic can lead to "bubble butt," where gas accumulates in the turtles' bodies, causing them to float and become easy prey for predators or starve.

The impact of plastic pollution on marine life is devastating, and immediate action is required to address this global crisis.

Air pollution affects animals' organs and immune systems, making them vulnerable to disease

Air pollution can have detrimental effects on the organs and immune systems of animals, making them more susceptible to diseases.

Effects on Organs

Air pollution can affect the lungs and cardiovascular systems of animals. For example, air pollutants can cause oxidative stress and inflammation, which can lead to respiratory issues and lung cancer. Additionally, air pollution can harm the skin of animals, causing allergic reactions and skin ageing.

Effects on the Immune System

Air pollution can also impact the immune system of animals. Pollutants can accumulate in the lungs, compromising immune surveillance and making animals more vulnerable to respiratory infections and other lung diseases. Air pollution can also affect the gut microbiome, which is linked to immune function.

Food Supply and Quality

Air pollution can contaminate the food supply of animals, leading to bioaccumulation of toxins in their tissues. This is especially true for top-level predators such as eagles and bears. Heavy metals, such as mercury, can be transported long distances through the air and accumulate in water bodies, making them toxic to fish and other aquatic life.

Habitat Degradation

Air pollution can also degrade animal habitats, making it difficult for some species to live and breed naturally. For example, acid rain can change the chemistry of soils and water bodies, making them uninhabitable for certain animals.

Wildfires are a leading cause of animal mortality, as seen in Australia's 2020 fires

Animals are extremely vulnerable to harm from pollution. Air pollution, for instance, can affect the quality of an animal's habitat and food supply. Persistent organic pollutants (POPs) and heavy metals, such as mercury, are particularly harmful. These substances can enter the food chain, damaging the supply and quality of food and causing bioaccumulation. This process results in higher concentrations of pollutants in top-level predators, leading to various health issues and even death.

Wildfires are a significant contributor to air pollution and a leading cause of animal mortality. The 2019-2020 bushfires in Australia serve as a devastating example. These fires, intensified by rising temperatures and prolonged drought, resulted in the loss or displacement of nearly three billion animals, according to a report by the World Wide Fund for Nature. This figure includes 143 million mammals, 2.46 billion reptiles, 180 million birds, and 51 million frogs. The impact of these fires on Australia's wildlife is considered one of the worst wildlife disasters in modern history.

The report, compiled by ten scientists from several Australian universities, revealed that the number of animals affected was nearly three times higher than earlier estimates. The scientists examined a fire impact area of 11.46 million hectares, studying the effects on different animal species. Professor Chris Dickman from the University of Sydney, one of the contributors, stated that it was challenging to comprehend the magnitude of the disaster.

The bushfires in Australia had a devastating and far-reaching impact on the country's wildlife. The interim report on the fires recommended several measures to mitigate the effects of such disasters in the future. These included improving habitat connectivity to aid species escape, identifying and protecting unburned habitats crucial for threatened species, and enhancing fire prevention and management strategies. Additionally, the report emphasized the urgent need for climate action to reduce the frequency and intensity of extreme fires.

The impact of the 2019-2020 bushfires in Australia highlights the vulnerability of animals to wildfires and the urgent need for preventative measures and climate change mitigation. With extreme fires becoming more frequent due to climate change, it is crucial to address this issue to minimize the loss of animal life and protect biodiversity.

Excess nutrients in water from fertilisers cause harmful algal blooms, creating dead zones

While it is challenging to determine the exact number of animals affected by pollution each year, it is evident that pollution, particularly plastic pollution, takes a heavy toll on wildlife. For instance, plastic pollution is responsible for the deaths of approximately 1 million seabirds and 100,000 sea mammals, turtles, and fish annually.

One significant way in which pollution affects aquatic life is through excess nutrients in water from fertilisers, which cause harmful algal blooms, ultimately creating dead zones.

Excess Nutrients in Water from Fertilisers

Fertilisers used in agriculture contain nutrients such as nitrogen and phosphorus, which are essential for plant growth. However, when excess amounts of these fertilisers are applied to crops or fields, or when manure is mismanaged, they can be washed into nearby waterways during rain events. This excess nutrient runoff provides an abundant source of nutrients for algae, leading to uncontrolled growth and the formation of harmful algal blooms (HABs).

Harmful Algal Blooms (HABs)

HABs occur when certain types of algae, such as cyanobacteria or "blue-green algae," grow out of control and produce toxins that are dangerous to fish, wildlife, and even humans. These blooms can occur in freshwater and coastal marine waters, including lakes, reservoirs, rivers, ponds, bays, and estuaries. The toxins released by HABs can contaminate drinking water, causing illnesses and deaths in both animals and humans.

Dead Zones

Dead zones are areas in water bodies, typically bays, lakes, and coastal waters, where aquatic life cannot survive due to extremely low oxygen levels caused by the overgrowth of algae. As the algae consume oxygen and block sunlight from reaching underwater plants, the water's oxygen levels deplete, making it impossible for fish and other aquatic organisms to survive. The Gulf of Mexico, for example, experiences a large dead zone of about 6,500 square miles every summer due to nutrient pollution from the Mississippi River Basin.

Persistent organic pollutants, like PCBs and DDT, accumulate in animals' tissues and pass up the food chain

Persistent organic pollutants (POPs) are toxic chemicals that can be transported by wind and water, allowing them to affect wildlife and people far from their source. They persist in the environment for long periods and can accumulate and pass from one species to another through the food chain. This process is known as bioaccumulation and biomagnification.

POPs include synthetic chemicals such as PCBs and DDT. PCBs, or polychlorinated biphenyls, were used as cooling fluids in electrical equipment due to their durability and resistance to fire. DDT, or dichloro-diphenyl-trichloroethane, was developed as an insecticide and was widely used during World War II to combat insect-borne diseases. Both PCBs and DDT were banned in the 1970s and 1980s, but they continue to persist in the environment and can be found in animal tissues.

Bioaccumulation occurs when toxins enter the food web by building up in individual organisms. This happens at the base of the food web, within primary producers like phytoplankton, which absorb POPs directly from seawater. The toxins accumulate in their tissues because they are absorbed from the water faster than they can be metabolized. As slightly larger organisms called zooplankton feed on the contaminated phytoplankton, they absorb the POPs into their tissues at a higher concentration. This is the beginning of biomagnification, where toxins pass from one trophic level to the next, increasing in concentration as they move up the food chain.

The impact of POPs bioaccumulation and biomagnification is evident in orca whales, which have accumulated high levels of PCBs, making them among the most contaminated marine mammals globally. Mother orcas pass these contaminants to their young through their milk, which has a high-fat content. PCBs are known to cause reproductive problems, and studies are investigating their other potential impacts on orcas.

The harmful effects of POPs extend beyond marine life. Studies have linked POPs exposures to declines, diseases, and abnormalities in various wildlife species, including certain kinds of fish, birds, and mammals. POPs can also have adverse health effects on humans, including reproductive, developmental, behavioral, neurologic, endocrine, and immunologic issues. People are mainly exposed to POPs through contaminated food, particularly animal and fatty foods, as these toxins are stored in fat tissues and increase in concentration as they move up the food chain.

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