Marine debris and litter
Marine debris and litter is a serious pollution issue that affects our waterways, coastline and ocean - impacting on wildlife, human health and the marine environment. Rivers, streams and stormwater drains transport litter hundreds of kilometres to the ocean where currents and winds then carry them all over the world.
Litter and marine debris in waterways pose a major threat to marine life, with the major impacts being ingestion or entanglement. However, litter and debris are also hazardous to humans, creating toxic waterways, carrying invasive species, depleting fisheries, requiring expensive clean up operations and ruining the aesthetics of the environment.
Plastics
Plastics can take over a century to break down and comprise 60-80% of all marine debris. Our heavy reliance on plastics means there is a need to produce environmentally degradable plastics that can break down at a much faster rate.
Impact on turtles
On average, a staggering 200 turtles are reported dead, injured or sick in Moreton Bay Marine Park every year. Turtles can become entangled and drown in discarded crab pots, fishing nets and rubbish. Turtles also mistakenly eat plastic debris, which once ingested can prevent food digestion and lead to a very slow and painful death. The cause of death of over 30% of stranded sea turtles in Moreton Bay is ingestion of marine debris. Marine debris impacts all six of the species of sea turtles found in Australia waters.
Marine turtles are particularly vulnerable to debris because of their downward facing spines, meaning they can swallow things easily but cannot throw them back up, so when they eat foreign objects it paralyses the gut and prevents them from digesting their food. This decomposing food emits gases which cause the turtle to float, making it more susceptible to boat strike or attack from predators.
Ecological impacts
Other ecological impacts of marine debris include the absorption of PCB’s (polychloroinated biphenols), long distance dispersal of invasive species and entanglement in and ingestion of debris by marine wildlife. Ingesting marine debris can lead to lethal and non-lethal effects such as reduction in nutrient absorption, resulting in decreasing growth rates and increasing the time to sexual maturation.
Find out more about the debris and the impact on waterways at www.healthywaterways.org.au
