Plastic Pollution: Impact On Jellyfish Ecosystems

Plastic pollution is a pressing issue that affects all marine life, including jellyfish. While plastic pollution can cause entanglement, suffocation, and starvation in most marine species, jellyfish have shown remarkable resilience and adaptability in the face of this global crisis. In this context, it is essential to understand how plastic pollution affects jellyfish specifically and explore any potential consequences for the broader marine ecosystem.

Jellyfish ingest plastic, which can cause starvation

Jellyfish are not exempt from the harmful effects of plastic pollution. In fact, they are highly susceptible to ingesting plastic, which can lead to starvation.

Jellyfish are often unable to distinguish plastic from their prey, leading them to consume plastic debris. This problem is widespread among marine animals, as plastic can resemble their natural food sources. For example, turtles eat plastic bags that look like jellyfish, and fish consume small plastic pieces that are similar in size to their regular meals.

The consequences of ingesting plastic can be severe for jellyfish. As they can consume up to 50% of their body weight, ingesting non-nutritious plastic can cause them to slowly starve. This issue is not limited to jellyfish, as they are preyed upon by larger animals in the Mediterranean, such as bluefin tuna, which are then consumed by people and marine mammals. This transfers the microscopic pieces of plastic consumed by jellyfish to larger species, including humans.

The attraction of jellyfish to plastic is a complex issue that researchers are still working to understand fully. One hypothesis suggests that ocean plastic, as it breaks down, is coated with a thin layer of biofilm or releases certain molecules that appeal to jellyfish.

To address this issue, scientists are planning experiments to identify what specific factors attract jellyfish to plastic. By understanding these attractants, researchers could work with manufacturers to develop plastic that is less enticing to marine organisms, reducing the harmful impact of plastic pollution on jellyfish and other marine life.

Plastic provides a surface for jellyfish to attach to and thrive

Plastic pollution in the ocean has been found to benefit jellyfish, providing them with more opportunities for survival. During the polyp phase of their life cycle, jellyfish must attach themselves to a surface in order to grow. In natural circumstances, jellyfish polyps settle on the ocean floor. However, with the influx of plastics in the ocean, jellyfish now have additional surfaces to attach to. As a result, jellyfish populations have expanded, as they are no longer restricted to coastlines and can thrive in deeper waters.

Jellyfish are highly opportunistic and adaptable, thriving in environments where other species struggle to survive. They have survived every mass extinction in Earth's history, according to fossil and sediment records. Their boneless bodies mean that pH imbalances in the ocean do not affect them as severely as marine species with skeletal structures. Additionally, jellyfish are able to outcompete other species for food as they are unaffected by rising temperatures.

The lifecycle of a jellyfish is complex, and the "medusa phase", which results in the distinctive bell-shape, occurs in the later phase of their life. Before this, jellyfish are produced as tiny larvae and float along with the tides. After maturing, they undergo a transformation into the "polyp phase". It is during this phase that they must attach to a surface to grow.

The increase in plastic pollution provides jellyfish with more opportunities to attach and grow, contributing to their population expansion. This has led to the clogging of beaches and competition for food with other species. As a result, the presence of plastic in the ocean has created an ideal environment for jellyfish to thrive in, while posing challenges for other marine life.

Jellyfish mucus can be used to filter microplastics

Jellyfish mucus has an absorbing property that can be used to filter microplastics from the ocean. The mucus can trap microplastics, which are not visible to the eye and are often not caught by seawater treatment plants due to their small size. These microplastics can enter our systems and harm our health.

Jellyfish mucus can trap these microplastics and make them stick to its surface, creating a giant blob of mucus and microplastics that is easier to extract and remove. This is a more efficient method than trying to filter all the microplastics from the water.

The GoJelly project, funded by the European Union's Horizon 2020 Innovation and Research Programme, is working to tackle the problem of microplastics in the world's oceans using jellyfish mucus. The project aims to use the mucus produced by jellyfish to create filters that can remove plastic particles from wastewater before it reaches the ocean.

The mucus contains a protein structure that acts like a net, trapping and filtering microplastics. The nomad jellyfish and the common moon jellyfish are the most promising species for developing the biofilters due to the quantity and quality of mucus they produce.

The process of creating the filters involves harvesting the medusae using a net and then transferring them to a funnel where they secrete the mucus. The collected mucus is then freeze-dried and inserted into a cylinder-shaped filtering device where the dried mucus layer is held in place by a layer of sand.

One challenge of the project is the absence of clear policy for reducing microplastics in wastewater. Without standards for microplastics in wastewater effluent, it is difficult to incentivize investment in innovative solutions.

Another challenge is scaling up the process. Collecting enough jellyfish and extracting the mucus on a large scale may be difficult, and the amount of mucus needed is still unknown. However, the project has the potential to be a gelatinous solution to microplastic pollution in the world's oceans.

Plastic can smell appetising to jellyfish

Jellyfish are fascinating, elegant creatures that are simple in their composition, yet complex in their ecological impact. They are primarily composed of water, with only about 5% of their body consisting of solid matter. Despite their simple structure, jellyfish play a crucial role in the ocean's food web and can even help combat plastic pollution.

While jellyfish were once considered insignificant in the ocean's food chain, recent studies have revealed that they are a vital food source for many species, including tuna and penguins. This discovery has led to a renewed understanding of their importance in maintaining stable ocean ecosystems.

However, one concerning aspect of their interaction with the environment is their attraction to plastic pollution. In a study published in the journal Scientific Reports, researchers from the Aquatilis Expedition found plastic debris trapped in the bodies and digestive systems of mauve stinger jellyfish in the Mediterranean Sea. This led them to believe that jellyfish were mistaking plastic for food.

So, why does plastic smell appetising to jellyfish? One possible explanation is the presence of a biofilm that develops on plastic as it begins to weather in the ocean. This biofilm, along with molecules released during the breakdown of plastic, may emit certain odours that attract hungry jellyfish.

Additionally, a study published in the journal Science Advances in 2016 found that algae growing on ocean plastic produce an odour called dimethyl sulfide as they break down. This odour is known to attract marine animals, including jellyfish, who mistake it for food.

The implications of jellyfish consuming plastic are concerning. Ingesting plastic can lead to health issues such as starvation, and as jellyfish are prey for larger animals, the plastic they consume can end up in the bellies of predators, including humans.

Plastic can be mistaken for prey

Plastic pollution in the ocean is a pressing issue, with 18 billion pounds of plastic entering the ocean each year. This plastic pollution has been shown to harm marine life, causing entanglement, suffocation, and starvation as animals' stomachs fill with debris.

Jellyfish are no exception to this, and plastic pollution can have a detrimental impact on their health and survival. One of the main ways plastic affects jellyfish is by being mistaken for prey. Jellyfish have been observed consuming plastic, with pieces of plastic found in their digestive systems. This behaviour is likely due to plastic resembling the jellyfish's natural prey.

In one notable example, a group of scientists from the Aquatilis Expedition found plastic trash trapped in the hoods or woven through the bodies of multiple mauve stingers in the Mediterranean Sea. When inspected more closely, four out of twenty jellyfish were found with plastic in their digestive systems, indicating they had attempted to eat it. Armando Macali, an ecologist and one of the study's authors, stated that the jellyfish seemed to be "in love with plastic".

This behaviour is not unique to jellyfish, with past studies showing that other marine animals also accidentally consume plastic. Turtles, for instance, eat plastic bags that resemble jellyfish, and fish consume small, rice-sized pieces of plastic that look like their usual food.

The attraction to plastic can also be attributed to the growth of algae on ocean plastic. As the plastic breaks down, it emits an odour called dimethyl sulfide that attracts hungry animals. This further increases the likelihood of jellyfish and other marine creatures mistaking plastic for prey.

The consumption of plastic by jellyfish can have significant health consequences. Ingesting large amounts of plastic can lead to starvation as it fills their stomachs, leaving no room for nutritious food. Additionally, as jellyfish are preyed upon by larger animals, the plastic they consume can enter the food chain, potentially impacting the health of other species, including humans.

Overall, the presence of plastic in the ocean poses a serious threat to jellyfish and other marine life. The resemblance of plastic to natural prey is a key factor contributing to the consumption of plastic by jellyfish, highlighting the urgent need to address plastic pollution and protect marine ecosystems.

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