Environmentalists have long expressed concern about the number of sea life that consume man-made materials. New research funded by the Australian Government backs these fears by showing almost all seabirds will eat some form of plastic within a few decades from now.
Researchers from the Commonwealth Scientific and Industrial Research Organization (CSIRO) and Imperial College London (ICL) have joined forces to work out how widespread the threat of plastic is for the world’s seabirds.
They found nearly 60 per cent of species already have plastic in their digestive systems.
Based on analysis of published studies since the early 1960s, researchers — led by CSIRO Dr. Chris Wilcox with fellow co-author Dr Denise Hardesty and the ICL’s Dr Erik van Sebille — found that plastic is becoming increasingly commonplace in the stomachs of seabirds.
In 1960, plastic was found in the stomachs of less than 5 per cent of individual seabirds, but this figure had risen to 80 per cent by the year 2010.
Based on current trends, researchers predict that plastic ingestion will affect 99 per cent of the world’s seabird species by the year 2050. Scientists estimate that 90 per cent of all seabirds have eaten some form of plastic, including shopping bags, bottle caps, and synthetic fibers from clothes that have washed out to sea through rivers, sewers, and waste water.
Birds sometimes mistake brightly colored objects for food, swallow them by accident, and suffer from blockage of the digestive tract, weight loss, or even death.
“For the first time, we have a global prediction of how wide-reaching plastic impacts may be on marine species — and the results are striking,” CSIRO Oceans and Atmosphere senior research scientist Dr. Wilcox said in a public statement.
“We predict, using historical observations, that 90 per cent of individual seabirds have eaten plastic. This is a huge amount and really points to the ubiquity of plastic pollution.”
Dr. Hardesty believes seabirds are excellent indicators of the health of the ecosystem.
“Finding such widespread estimates of plastic in seabirds is borne out by some of the fieldwork we’ve carried out where I’ve found nearly 200 pieces of plastic in a single seabird,” she said.
Researchers found plastics have the greatest impact on wildlife when gathered in the Southern Ocean in a band around the southern edges of Australia, South Africa, and South America.
Dr. van Sebille, from the Grantham Institute at Imperial College London, said plastics have the most devastating impact where there is a great diversity of species.
“We are very concerned about species such as penguins and giant albatrosses, which live in these areas,” he said.
“While the infamous garbage patches in the middle of the oceans have strikingly high densities of plastic, very few animals live here.”
However, there is still a chance to reduce the impact plastic has on seabirds.
“Improving waste management can reduce the threat plastic is posing to marine wildlife,” Dr Hardesty said.
“Even simple measures can make a difference, such as reducing packaging, banning single-use plastic items, or charging an extra fee to use them, and introducing deposits for recyclable items like drink containers.
“Efforts to reduce plastics losses into the environment in Europe resulted in measureable changes in plastic in seabird stomachs within less than a decade, which suggests that improvements in basic waste management can reduce plastic in the environment in a really short time.”
The Chief Scientist at the Washington, D.C.-based environmental advocacy group Ocean Conservancy, Dr. George H. Leonard, agrees the study demonstrates how widespread plastics are in oceans.
“Hundreds of thousands of volunteers around the world come face-to-face with this problem during annual Coastal Cleanup events,” he said.
“Scientists, the private sector, and global citizens working together against the growing onslaught of plastic pollution can reduce plastic inputs to help protect marine biodiversity.”
The work was carried out as part of a national marine debris project supported by CSIRO and Shell’s Social investment program, as well as the marine debris working group at the National Center for Ecological Analysis and Synthesis based at the University of California in Santa Barbara — with support from Ocean Conservancy.