Ocean
plastic plague threatens seabirds
Chris
Wilcox, Britta Denise Hardesty & Erik van Sebille, The
Ecologist
Many of you may have already seen the photographs of albatross
carcasses full of undigested plastic junk. But how representative is that of
the wider issue facing seabirds?
To help answer that question, we carried out the first worldwide
analysis of the threat posed by plastic pollution to seabird species worldwide.
This figure is based on reviewing previous reports in the
scientific literature, but if we use a statistical model to infer what would be
found at the current time and include unstudied species, we expect that more
than 90% of seabirds have eaten plastic rubbish.
Our analysis of published studies shows that the amount of plastic
in seabird's stomachs has been climbing over the past half-century. In 1960,
plastic was found in the stomachs of less than 5% of seabirds, but by 2010 this
had risen to 80%.
We predict that by 2050, 99% of the world's seabird species will
be accidentally eating plastic, unless we take action to clean up the oceans.
Some areas of contain as many as 580,000 plastic pieces per square kilometre.
The surprse - it's worst in the remote Southern Ocean
Perhaps surprisingly, we also found that the area with the worst
expected impact is at the boundary of the Southern Ocean and the Tasman Sea,
between Australia and New Zealand.
While this region is far away from the subtropical gyres, dubbed
'ocean garbage patches', that collect the highest densities of plastic, the
highest threat is in areas where plastic rubbish overlaps with large numbers of
different seabird species - such as the Southern Ocean off Australia.
Seabirds are excellent indicators of ecosystem health. The high
estimates of plastic in seabirds we found were not so surprising, considering
that members of our research team have previously found nearly 200 pieces of
plastic in a single seabird.
These items include a wide range of things most of us would
recognise: bags, bottle caps, bits of balloons, cigarette lighters, even
toothbrushes and plastic toys.