Plasticosis, a new disease in seabirds | The plastic enemy
A plastic bottle floats in the water.
The ingestion of plastic waste causes a new disease in seabirds that has just been described for the very first times in the scientific literature: plasticosis.
This disease has so far only been observed in pale-footed puffins that inhabit Lord Howe Island, about 600 kilometers off the coast of Australia, but there is no reason why. to believe that the same problem does not affect other birds or other mammals, the study's lead author pointed out.
There's nothing out of the ordinary about the physiology of these birds or the composition of the plastic, said Professor Alex Bond, senior curator of birds at the Natural History Museum in London, during an interview. x27;a conversation with The Canadian Press.
Whales tend to eat soft plastic, like bags, and it may not have the same impact. But for species that ingest hard plastic, there's nothing out of the ordinary about this species, so no doubt it could happen in other animals.
< p class="e-p">Pale-footed puffins on Lord Howe Island are considered by some experts to be the most plastic-contaminated birds on the planet.
Rather than just studying birds whose death may have been caused by plastic, Professor Bond and his colleagues looked at what he called the sub-lethal impacts of plastic, i.e. what happens inside the body. #x27;birds that may look healthy from the outside.
Researchers have found that plastic debris ingested by birds causes chronic inflammation that damages the stomachs and digestive tracts of birds, which then impairs their growth and compromises their survival.
These debris, Professor Bond pointed out, are not the [plastic] microbeads everyone is worried about, and they can be the size of a two dollar coin.
Plasticosis specifically affects the proventriculus, the first stomach chamber of birds.
Inflammation prevents injury to the stomachs of birds from the plastic to heal properly. An abnormal amount of scar tissue then forms, which makes the stomach less flexible and smoother than a normal stomach, Professor Bond said, and therefore less efficient at digesting food.
Researchers have also found that plastic debris damages the tubular glands of birds, which can make them more susceptible to infections and parasites, in addition to impairing the absorption of vitamins.
“The more plastic birds ingest, the more plasticosis damages their stomachs. But birds that ingest natural hard bits, like pumice stones, don't have the same reaction. So it seems to be associated with the extent of plastic ingestion.
—Alex Bond, Senior Curator of Birds at the Natural History Museum, London
And the problem is not confined to adult birds. Up to 90% of baby birds are contaminated by plastic regurgitated by their parents. In the most extreme cases, the cubs do not survive since their stomachs are filled with plastic which they are unable to digest.
British researchers have also established a direct correlation between the amount of plastic in the stomachs of baby birds and the length of their wings. They also found an association between the number of plastic pieces and the total weight of the bird.
Pale-footed puffins, Prof Bond said, lay their eggs towards the end of January. When the researchers arrived on site, around the end of April, the chicks were 80 or 90 days old and had just begun to emerge from their underground nesting boxes.
So all the plastic in the baby birds was given to them by their parents 90 days ago, he explained. And we see that the chicks that contain the most plastic are lighter when we catch them or when we find them dead on the beach. Their wings tend to be shorter. Their beak growth is not complete. And there are other physiological effects, like their blood chemistry or the scarring in their stomach.
Some baby birds carry 10% of their body weight in plastic, he added, by the time they have to fly to the Sea of Japan, learn to feed themselves for the first time and find the way to Lord Howe Island after five years, so definitely it's having an impact, said Mr. Bond, who compares the situation to a human being asked to run a marathon without training while having in his stomach 10% of its body weight in indigestible matter.
This study also allows in a certain way to take the pulse of the marine ecosystem, he underlined. Compared to other environmental contaminants like mercury, PFAS, or even chemicals that melted the ozone layer, very little is known about the impact of plastic on ecosystems. , according to him. And if we want to improve the state of the planet, we have to understand what is going on.
“There is difficult to measure the concentration of plastic in the sea. Seabirds can essentially be our eyes and ears. The healthier the seabirds, the more we can deduce that the oceans are doing a little better. They serve as a bit of a marker for the health of the entire marine ecosystem.
—Alex Bond, Professor
And when you find a dead bird, the researcher concluded, it doesn't really matter whether its death has was caused by plastic. We know with a fairly good degree of accuracy that there is nothing beneficial for a bird to have plastic in their stomach, he dropped.
< p class="e-p">The observations of Professor Bond and his team have been published by the Journal of Hazardous Materials.