Albatross And Turtles: Plastic Diet Mystery

Albatrosses and leatherback turtles are two species that are facing a crisis due to the mass consumption of plastic. Albatrosses, which are incredible birds with a wingspan of over 6 feet, often accidentally eat plastic while skimming the surface of the water with their beaks to catch fish, squid, and other seafood. Leatherback turtles, the largest sea turtles on Earth, also have a diet primarily consisting of jellyfish, which they can easily confuse with plastic bags and other plastic waste floating in the ocean. The issue of plastic consumption is not limited to these two species, and it is estimated that 52% of the world's turtles have eaten plastic waste. This is a pressing issue that requires immediate attention, and it is essential that we all work together to reduce plastic pollution and hold governments and corporations accountable for their role in this pollution epidemic.

Albatrosses are attracted to the smell of plastic

Albatrosses, petrels, and shearwaters are tube-nosed birds that soar across the open oceans, relying on their keen sense of smell to find food. For them, DMS is intensely alluring.

In 2019, Barbera-Tomas et al. analyzed social media groups, TED Talks, photo journals, and videos dedicated to reducing plastic use. They found that images of an albatross skeleton filled with plastic were particularly effective in motivating people to change their plastic use habits.

Albatrosses swallow floating items, digest the eggs, and regurgitate the indigestible material in a bolus. When the birds eat oddly shaped plastic, it can be difficult to regurgitate and can lead to serious health implications. Sharp plastic can puncture a bird's stomach and digestive tract. Additionally, an albatross's stomach can become so full of plastic that it is unable to eat and will starve to death.

In 1987, researchers found that 90% of Laysan Albatross chicks had plastic in their digestive tracts. This number has not decreased over time, but awareness of the problem is growing.

Albatross chicks are fed plastic by their parents

Albatross parents take turns foraging hundreds of miles at sea to find food for their offspring. They feed on squid, krill, and fish eggs by skimming the ocean's surface with their beaks. However, they often accidentally swallow floating plastic and bring it back to their chicks. As a result, albatross chicks are inadvertently fed plastic by their parents, leading to severe health issues and even death.

Albatross chicks are vulnerable to the harmful effects of plastic ingestion. Sharp plastic pieces can puncture their stomachs and intestines, causing internal injuries and potentially fatal blockages. Plastic debris can also absorb toxic pollutants from seawater, releasing them into the chicks' bodies. Additionally, the presence of plastic in their digestive system can create a false sense of fullness, leading to malnutrition and dehydration.

Photographer Chris Jordan's images of dead albatross chicks on Midway Atoll, with their stomachs filled with plastic, sparked worldwide environmental activism. These photographs highlighted the devastating impact of plastic pollution on albatross populations and served as a powerful statement about the far-reaching consequences of human consumption.

The problem is particularly acute for Laysan albatrosses, which breed on Midway Atoll. Their feeding technique of skimming the water's surface makes them more susceptible to ingesting floating plastic. As a result, many chicks on the island suffer from plastic ingestion, leading to health issues and reduced survival rates.

To address this issue, efforts are being made to reduce consumer demand for single-use plastics and encourage governments to implement more effective recycling programs. It is crucial to recognize that the plastic ingested by albatross chicks comes from widespread human consumption, and individual actions to reduce plastic waste can have a significant impact on mitigating this global issue.

Plastic pollution is increasing

Albatrosses are attracted to plastic because of the way it looks and smells, or if it is covered in food. They skim the surface of the water with their beaks to catch fish, squid, and other seafood, inadvertently swallowing floating plastic items. The plastic is then regurgitated in boluses, similar to owl pellets, along with indigestible natural materials. However, when albatrosses swallow oddly shaped plastic, they can have difficulty regurgitating it, leading to serious health issues. Sharp plastic can puncture their stomachs and digestive tracts, and large amounts of plastic can fill their stomachs, causing them to starve.

Leatherback turtles have a diet primarily composed of jellyfish, and they often ingest plastic bags that resemble their prey. Research suggests that 52% of the world's turtles have eaten plastic waste. Smaller turtles tend to ingest more plastic, possibly due to a lack of experience in choosing the right food. The ingestion of plastic can cause internal organ rupture, intestinal blockages, and unnatural buoyancy, which can stunt growth and slow reproduction rates. Even ingesting just one plastic item can be fatal for 22% of turtles.

The increasing plastic pollution poses a significant threat to these species, with devastating consequences. While individual efforts to reduce plastic waste are important, government intervention and global initiatives are necessary to address this urgent issue effectively.

Leatherback turtles mistake plastic for jellyfish

Leatherback turtles are the largest sea turtles on Earth, and their diet consists almost entirely of jellyfish. They are known as gelatinivores, meaning they feed on invertebrates such as jellyfish and sea squirts. The throats of leatherbacks have spikes, called papillae, that help move and cut up slippery jellyfish as they move down their digestive tract.

Unfortunately, leatherback turtles often mistake plastic for jellyfish. Plastic bags and other plastic waste floating in the ocean can look deceptively similar to jellyfish, and leatherbacks are unable to distinguish between the two. This is a serious issue as ingesting just one plastic item can be fatal for turtles. Sharp plastics can rupture their internal organs, and bags can cause intestinal blockages, leading to starvation.

The problem is made worse by the fact that plastic bags can also smell like food to sea turtles. Over time, microbes, algae, plants, and tiny animals start to colonize the plastic bags, creating a scent that attracts turtles and other marine animals. This instinctively guides them towards the plastic, which they believe is food.

Research suggests that 52% of the world's turtles have eaten plastic waste, and leatherback turtles are particularly susceptible due to their jellyfish-heavy diet. Smaller turtles also tend to ingest more plastic, possibly because they are less experienced and more likely to make mistakes in their food choices.

The ingestion of plastic has severe consequences for leatherback turtles and other sea turtle species. It can cause intestinal blockages, leading to starvation and death. Even if they survive ingestion, consuming plastic can negatively impact their growth, buoyancy, and reproduction rates.

Plastic ingestion causes intestinal blockages in turtles

Plastic ingestion is a well-documented threat to sea turtles, with both lethal and sublethal effects reported. The threat of plastic ingestion is poorly studied in non-marine turtles, but it is known to be a major problem for marine turtles, with research suggesting that 52% of the world's turtles have eaten plastic waste.

Leatherback turtles, or Dermochelys coriacea, are often mentioned as a species that suffers from plastic ingestion due to their diet, which primarily consists of jellyfish. Floating plastic bags can easily be mistaken for jellyfish, and ingestion of plastic by leatherback turtles is common.

Green turtles, or Chelonia mydas, are also common victims of plastic ingestion. Amounts as small as 1 gram can be enough to kill juvenile green turtles by blocking their guts. While the diet of adult green turtles is composed mainly of seagrass and algae, they are known to ingest animal matter when they are young, and this may be a strategy to survive when their main food source is scarce. As most of the floating material in the ocean is now plastic rather than the dead animals that it was in the past, this strategy has become a deadly trap.

The ingestion of plastic can cause intestinal blockages in turtles, leaving them unable to feed and resulting in starvation. Sharp plastics can also rupture internal organs. In addition, consuming plastic can make turtles unnaturally buoyant, which can stunt their growth and lead to slow reproduction rates.

The problem of plastic ingestion is not limited to marine turtles. In a study of 65 freshwater turtles, it was found that 7.7% had ingested plastic. Of these, two turtles had plastic only in their stomachs, while three turtles had plastic only in their intestines.

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