Microplastics collecting in lobster larvae

Microplastics in water seem to be able to get into lobster larvae in at least two separate ways, according to research at Maine's Bigelow Laboratory of Ocean Science.

Microplastics are bits of plastic smaller than 5 mm. They come from many sources, including laundry and some cosmetic products. Their most common form is tiny threads.

Senior research scientist Paty Matrai said research has focused largely on the impact of microplastics on adult marine organisms, and she wanted to know if larvae were affected at all.

Mistaking microplastics for food is the most common way for microplastics to end up in animals, but Matrai found that was not the only way they got into the lobster larvae.

"In addition to some larval stages eating the fibres, we saw that many of them accumulated the fibres under their carapace. We did not expect that," she said.

Madelyn Woods/Bigelow Laboratory for Ocean Sciences
Madelyn Woods/Bigelow Laboratory for Ocean Sciences

This was a particular problem for early-stage larvae, which did not seem to be able to effectively clear out the fibres.

At this stage of life the larvae are so small it is difficult to measure their size, so the researchers instead measured their capacity to breathe in an effort to determine how their health might be affected. The study found respiration capacity was impeded by the microplastics.

This is one of a number of factors harming populations in the Gulf of Maine, Matrai said. Ocean warming and acidification are also problems for lobsters.

"It is the potential synergy or interaction between three factors that I think will have the largest effect," she said.

"It is the fact that they are getting hit with more than one thing at a time right now. That is the problem."

Matrai hopes other researchers will pick up on her research and investigate how other larvae are being affected by microplastics.

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