jellyfish

Life In The Great Pacific Garbage Patch | Earth Wise

June 14, 2022 By EarthWise Leave a Comment

The world’s oceans contain five gyres, which are large systems of circular currents created by global wind patterns and the Earth’s rotation. Gyres act like gigantic whirlpools. Anything that floats into one of them eventually ends up in the center. Ever since floating plastic waste started entering the ocean, it has poured into these gyres and created so-called garbage patches. The largest of these is the Great Pacific Garbage Patch, located halfway between Hawaii and California. According to the Ocean Cleanup Foundation, the Great Pacific Patch contains at least 79,000 tons of plastic.

A recent study has shown that the garbage patch is not just a place where drifting plastics aggregate; it is also a place where drifting animals aggregate.

It turns out that the Great Pacific Garbage Patch is absolutely teeming with life, primarily small surface-dwelling animals that are collectively known as neuston. A ship surveying the garbage patch found that in some places, there were nearly as many neuston as there are pieces of plastic.

Typical creatures in the patch are blue dragon nudibranchs, Portuguese man-o-wars, anemones, sea snails, blue buttons (which are related to jellyfish) and hydrozoans. It appears that these creatures are reproducing within the garbage patch. Little is actually known about the life history and ecology of these creatures, so that studying the garbage patch is offering valuable insights to scientists.

Two nonprofit organizations are working to remove floating plastic from the Great Pacific Garbage Patch. Evidently, removing this existing pollution from the ocean is likely to have unexpected effects on the local ecosystem and is a source of at least some controversy. One thing that isn’t controversial, however, is that we need to stop the flow of plastic into the ocean.

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The Ocean’s Biggest Garbage Pile Is Full of Floating Life

Photo, posted in April, 2012, courtesy of Steven Guerrisi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Vanishing Kelp Forests | Earth Wise

June 25, 2021 By EarthWise Leave a Comment

Bull kelp is the dominant species in offshore kelp forests north of Santa Cruz, California along the west coast of North America. Bull kelp has similar physical structures to terrestrial plants; it anchors to the ocean floor with root-like structures called holdfasts, and has stem-like structures called stipes from which leaf-like blades stretch out through the water, absorbing nutrients and sunshine.

These giant seaweeds form lush underwater forests in northern California’s coastal waters and have long provided critical habitat for many species like salmon, crabs, and jellyfish. But now, for much of the California coast, only a few patches of bull kelp remain.

A team from University of California Santa Cruz has studied satellite images of about 200 miles of coastline. They found that starting in 2014, the area covered by kelp has dropped by more than 95%.

The die-off was driven in part by an underwater heat wave that depleted nutrients in the water and made it harder for the kelp to grow. Making matters much worse, populations of purple sea urchins, which eat kelp, have exploded in the region because of overfishing and other reductions in urchin predators such as sea otters. The sea urchins eat kelp holdfasts, creating so-called urchin barrens where their destructive grazing has decimated kelp forests.

Bull kelp is a species at high risk of becoming endangered. In coming decades, more marine heatwaves are expected. These events as well as stronger El Niños will become more common and frequent with climate change. Between these thermal events and the sea urchins, it will be difficult for kelp forests to survive.

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Ninety-five percent of bull kelp forests have vanished from 200-mile stretch of California coast

Photo, posted October 28, 2015, courtesy of Florian Graner/Green Fire Productions via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

PPE Pollution | Earth Wise

June 25, 2020 By EarthWise Leave a Comment

While the COVID-19 pandemic and its shutdown of so many human activities has reduced many kinds of pollution, it has also managed to create a new source of pollution: face masks and sanitary gloves.

Divers from a French non-profit organization called Operation Clean Sea are already finding gloves, masks, and hand sanitizer bottles beneath the waves of the Mediterranean, along with the usual litter of disposable cups and aluminum cans. In France, authorities have ordered 2 billion disposable masks. Given that, there may soon be the risk of having more masks in the Mediterranean than jellyfish. In Hong Kong, face masks have been piling up on beaches and nature trails. Even in Hong Kong’s isolated and uninhabited Soko Islands, dozens of masks are showing up on a small stretch of beach.

Disposable masks may feel like soft cotton, but almost all of them are made from non-biodegradable material such as polypropylene. When such masks are discarded into storm drains, they end up in rivers and seas. With a lifespan of hundreds of years, these masks are an ecological timebomb. Land-based activity accounts for 80% of ocean pollution, and half of that is a direct result of single-use plastics. Many of the CDC’s recent recommendations for reopening offices and businesses actually recommend the increased use of them, and for sensible reasons.

The best we can all do is to wear reusable masks and to try to wash our hands more often rather than putting on another pair of latex gloves. Given that there are alternatives, we don’t need to make plastic the solution to protect us from Covid-19.

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COVID-19 Masks Are Polluting Beaches and Oceans

Photo, posted March 28, 2020, courtesy of Michael Swan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mistaking Plastic For Food

September 27, 2019 By EarthWise Leave a Comment

Green sea turtles are one of the world’s largest species of turtle, with some measuring close to four feet long and weighing up to nearly 300 pounds. Their range extends throughout tropical and subtropical seas around the world, with the largest nesting populations found in Costa Rica and Australia.

Green sea turtles get their name from the green layer of fat under their shell, as opposed to their shell itself, which can be brown, green, yellow, and/or black. Scientists believe the green coloring of their fat is a result of their diet. Unlike most other sea turtles, green sea turtles eat marine plants such as seaweed and seagrass.

But new research suggests that green sea turtles are also more likely to swallow plastic because it resembles their natural diet. The scientists from the University of Exeter and the Society for the Protection of Turtles who examined green sea turtles that washed up on beaches in Cyprus found they favored narrow lengths of plastic in natural colors (like green and black) as opposed to debris of other shapes and colors.

Researchers were able to examine the full gastrointestinal tract of 19 green sea turtles. They found pieces of plastic inside every one of them, with the number of pieces ranging from three to 183. Smaller turtles tended to contain more plastic, possibly because they are less experienced or because diet choices change with age and size.

Previous research has suggested that leatherback sea turtles also eat plastic that resembles their food: jellyfish.

Researchers hope these findings will help motivate us to continue to work on reducing our overall plastic consumption and pollution.

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Green turtles eat plastic that looks like their food

Photo, posted September, 2007, courtesy of Brock Roseberry via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is The World’s Largest Sea Turtle No Longer Endangered?

January 29, 2018 By EarthWise 3 Comments

The rapid disappearance of many plants and animals around the world has many scientists saying we are experiencing a sixth mass extinction – the first since the dinosaurs were wiped out some 66 million years ago. Despite all sorts of conservation efforts, living things are struggling as a result of climate change, habitat loss, and countless other natural and manmade pressures. Conservation success stories have been few and far between.

Energy From Jellyfish

February 7, 2017 By EarthWise

Jellyfish are fascinating in appearance but generally are nothing but trouble. Their stings can ruin a tropical vacation but they can cause far more damage than that.