Gray whales feeding off the Oregon coast consume 21 million microparticles a day. Oregon State University reports.
Researchers’ attention concentrated on 230 gray whales that winter off the coasts of California and Mexico and summer off the coast of British Columbia in the north of the continent. The authors collected zooplankton, an important food source for gray whales, for analysis.
“We determined the calorie content of several zooplankton species and then wanted to find out how loaded these objects were with microparticles to get a better picture of their quality as prey,” said Lisa Hildebrand. Microparticle analysis was performed on 26 zooplankton samples collected from whale feeding areas. A total of 418 microparticles, more than 50% of which were fibers, were identified.
The authors then combined this data with estimates of the energy requirements of lactating and pregnant female gray whales to measure how much zooplankton and microparticles they consumed per day. It turns out that lactating and pregnant whales consume between 6.5 and 21 million microparticles per day. This estimate is minimal as whales can extract additional plastic directly from the water during filtration.
Pollution of seas and rivers with plastic is a big problem for the environment. Plastic practically does not decompose in natural conditions, but greatly disturbs the comfort of others, harms animals that eat it, and turns into microplastics that accumulate in tissues and are harmful to health. Many marine animals are unable to separate plastic from their normal food or filter it the way filter organisms do.