Barefoot Beach Walkers In Maine Have Feet Dyed Black In Mysterious Insect Mass Die-Off


Rachael Funnell

Social Editor and Staff Writer

clockJun 11 2021, 17:12 UTC
Barefoot Beach Walkers In Maine Have Feet Dyed "Mass Die Off" Black

Lint model's own. Image credit: Koldunov/

There are few pleasures so simple in life as the feeling of warm sand between your bare toes as you look out at the ocean. The idyllic scene however might be tainted somewhat if you were to return home to find the soles of your feet inexplicably stained black. That’s what’s been happening to people visiting the shores of Maine and New England sans-footwear recently, but the culprit is thought to have finally been pinpointed.

One affected stroller was Jenny Greenleaf who spoke with the New York Times about their perplexing experience. Greenleaf had visited the beach for a barefoot stroll only to return home and find their feet stained by a substance that didn’t appear to have an oil-like texture, a historically common contaminant of beaches. According to a video report from News Center Maine (below), the substance was found not to be petroleum-based, which got people understandably worrying about what else it might be.


According to AP, marine geologist with the Maine Geological Survey Steve Dickson decided to step up to the challenge. Working with two local retired oceanographers, they took samples to investigate further with the help of a microscope and curiously found the black stuff to be millions of miniature insects. “This is the first time I’ve seen or heard of this in my 35 years,” said Dickinson to AP.


The incident was reported on by Jim Britt, a spokesman for Maine’s Department of Agriculture, Conservation and Forestry, who explained that the creatures appear to be kelp flies. These teeny bugs feed on decaying seaweed so are a common inhabitant of beaches. For some reason, it appears they have died in their millions along certain stretches of beach where they are staining the feet of passersby. They create a naturally occurring pigment in a similar way to cochineal red that’s derived from crushed-up beetles.

It’s hoped that pinpointing the exact species of kelp fly might bring more answers, but for now Britt has expressed that beyond being a bit smudgy the bugs pose no obvious threat to human health.


While potentially less ecologically devastating than an oil spill, there are some for whom perhaps a bit of petroleum might have been a tad less disgusting. “...It's actually horrifying; the stains are likely from the unexplained and unprecedented MASS DEATH of MILLIONS of tiny kelp flies off the coast of Maine, gotta love it…” wrote a Twitter user.

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