Download Button Example

A right whale with her calf. (NOAA) — Representational Image
(NOAA)

From the food we eat to the water we drink, microplastics are everywhere. And while they've invaded nearly every abiotic layer of Earth, our oceans, in particular, have taken a massive hit. Studies estimate that upper oceans consist of over 25 trillion pieces of microplastics – that's roughly 82,000 to 578,000 tons of plastic!

So it comes as no surprise that a majority of fish in the ocean have considerable amounts of microplastics in their body, with an average fish having about 5.5 pieces in their bodies. Now, if a little fish can have that much plastic in its body, how much do you think a whale a hundred times its size might have?

We might have an answer for you!

A recent analysis, led by researchers at Stanford University, looked into ocean plastic pollution and whale foraging behaviour to estimate how much plastic was going into the animals' systems.

Between 2010 and 2019, they tracked the whales with noninvasive tags that revealed that they were ingesting tiny specks of plastic in far larger quantities than previously thought – an estimated 10 million pieces per day, to be precise.

Moreover, almost all of it comes from the fish and krill they eat, not the water they gulp.

"They're lower on the food chain than you might expect by their massive size, which puts them closer to where the plastic is in the water. There's only one link: The krill eat the plastic, and then the whale eats the krill," said study co-author Matthew Savoca, a postdoctoral scholar at Hopkins Marine Station, Stanford's marine laboratory on the Monterey Peninsula.

The whales predominantly fed 50 to 250 metres below the surface, a depth that coincides with the highest concentrations of microplastic in the open ocean. And baleen whales, in particular, are at the highest risk owing to the amount of food they eat and their habitat overlapping with polluted areas such as the California Current that flows south along North America's western coast.

"We need more research to understand whether krill that consume microplastics grow less oil-rich and whether fish may be less meaty, less fatty, all due to having eaten microplastics that gives them the idea that they're full," said Kahane-Rapport, the study's lead author.

"If patches are dense with prey but not nutritious, that is a waste of their time because they've eaten something that is essentially garbage. It's like training for a marathon and eating only jelly beans."

As for the effect of these microplastics on the whales, researchers think that it could be scratching their stomach linings, getting absorbed into the bloodstream or passing through the animal.

The study's findings represent an essential first step toward understanding the potential chemical and physiological effects of microplastics on whales and other large filter-feeding animals.

This study’s results are detailed in Nature Communications and can be accessed here.

For weather, science, space, and COVID-19 updates on the go, download The Weather Channel App (on Android and iOS store). It's free!

POLLUTION

Whales Are Consuming As Much As 10 Million Pieces of Microplastics Each Day, Reveals a Stanford Study