Coral bleaching isn’t the only major issue affecting our coral reefs. Plastic waste is once again damaging marine life, this time in the form of the coral reefs. Scientists around the world including those at Cornell University and James Cook University in Queensland, Australia found that corals entangled in plastic are more likely to be infected with pathogens and diseases then ones which aren’t. These scientists surveyed 159 coral reefs and visually examined over 120,000 individual corals all throughout the Asia pacific region. Of the corals surveyed, 1/3 of them were wrapped in at least one piece of plastic greater then 50mm amounting to 2.0-10.9 plastics per 100m2. It was then found that corals within the presence of plastic waste saw a likelihood of contracting a disease increase by more than a factor of 20 to 89.1 ± 3.2%. This is a significant jump from that of the normal rate in corals which is 4.4 ± 0.2%. Given the widespread distribution of plastic debris on coral reefs and the continued pollution rates, by 2025 it was estimated that if everything continues as it is, over 15.7 billion plastic items will be wrapped up in coral reefs, meaning huge increases in mortality rates, which 3/4 of the plastic debris causing diseases eventually lead to.
With over 275 million people worldwide relying on coral reefs as food sources, this plastic waste is a major problem. The hard part is, plastics aren’t uni-formally distributed. More waste is found closer to poorer regions of the world, as they tend to recycle less and pollute more. These third world countries also tend to rely more heavily on the ocean, particularly coral reefs, as their main food source, thus this phenomenon is only gonna affect them to a higher degree. For example the study found Indonesia (a third world country) had the highest amount of plastic debris in their surrounding regions and thus also had the highest percentage of coral reefs in contact with plastics, compared to everywhere else studied
The overall impact? Not good. It has been stressed over and over again and will continue to be; waste management is a must. Decreasing amounts of debris that enter the ocean is imperative to marine life as well as our own. It is vital that we reduce the amount of plastic on our coral reefs and thus the associated diseases they cause.
Lamb J. B. et al., 2018. Plastic waste Associated with Disease on coral reefs. Science Vol. 359(6374): 460-462.