A recent study on the impact of marine plastics on animal mortality has revealed that sea turtles are more susceptible to micro and macroplastic ingestion compared to marine mammals and sea birds.
The researchers state that almost half of the sea turtles examined had ingested macroplastics, with many consuming multiple pieces. In fact, most of the turtles had over 10 pieces of hard plastics, soft plastics, and fishing debris in their stomachs.
Video: Researchers Remove Plastic Drinking Straw From Sea Turtle’s Nostril
The majority of these ingested plastics were small in size (with a mean piece size of only 0.22 cm3). However, more than half of the individuals in the study had plastic pieces larger than 1 cm. Shockingly, out of all the sea turtles studied, it was found that 8.4 percent of deaths were caused by plastic ingestion. The researchers have termed these incidents as known debris deaths (KD). Additionally, 0.8 percent of the turtle deaths were categorized as probable debris deaths (PD).
Plastic Loads
the study also revealed that a single adult sea turtle with a plastic load of 93 pieces measuring ≥5mm has a 50 percent chance of death, while those with a load of 342 pieces measuring ≥5mm have a staggering 90 percent chance of mortality.
Similarly, small juveniles with a plastic load of only 105 pieces measuring ≥5 mm have a high risk of death (50%), while those with a load of 377 pieces measuring ≥5 mm face an alarming mortality rate of up to 90%.
Sea Turtle Rescued From Fishing Line Poops Out Plastic Balloon During Treatment
Out of all the animals studied (marine mammals and sea birds), sea turtles were found to be the most affected by plastic ingestion and death. The study reported that almost 50 percent of the sea turtles had ingested plastic, while only 35 percent of the sea birds and 12 percent of marine mammals had consumed plastic.
Sea Turtle Deaths From Plastics
The researchers also noted that ingested plastics were responsible for 4.4 percent of all necropsied turtle deaths, with a majority occurring in post-hatchlings and juveniles. This could be attributed to the fact that green sea turtles (Chelonia mydas) have a more generalist diet, making them more prone to consuming various types of plastics. Additionally, juvenile turtles are at a higher risk due to their increased exposure to plastic debris compared to adult turtles.
The research team consisted of members from Ocean Conservancy, Institute for Marine and Antarctic Studies, University of Tasmania, Ecology and Conservation in the Anthropocene (ECOA) Lab, Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Alagoas in Brazil, as well as from the Department of Ecology and Evolutionary Biology at the University of Toronto.
The complete study titled “A quantitative risk assessment framework for mortality due to macroplastic ingestion in seabirds,
marine mammals,
and sea turtles” can be accessed on Proceedings
of
the National Academy
of Sciences website.
This is heartbreaking to hear, we need to do more to protect these animals from plastic pollution.