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Emperor penguins, the tallest and heaviest of all living penguins, are also the most famous, being the subject of a very popular documentary film. The ongoing loss of sea ice in Antarctica has led to unprecedented breeding failures in emperor penguin colonies.

Since 2016, Antarctica has seen the four years with the lowest sea ice extent on record. Between 2018 and 2022, 30% of the 62 known emperor penguin colonies were affected by partial or total sea ice loss. Current predictions suggest that the population of emperor penguins will fall by 99% by the end of the century.

To monitor remote emperor penguin colonies, researchers use satellite images in which the brown stains of the birds’ guano stand out against the white ice and snow.

Researchers at the British Antarctic Survey have launched the ‘Polar Observatory’ on the online citizen science website Zooniverse to recruit ‘penguin detectives’ to help validate the accuracy of satellite images in assessing penguin populations.

The online app contains drone photos taken over the Snow Hill penguin colony. The images have been split into more than 300 10-meter squares. Volunteers are asked to identify any adult and chick penguins in a given picture. The results will be fed into machine learning algorithms to train the AI systems in automatically counting penguins in future surveys.

The project is a fun opportunity for aspiring conservationists and penguin lovers in general to help learn more about the future of the species. Interested people can learn more on the Zooniverse website.

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‘Penguin detectives’ required for new counting app

Polar Observatory

Photo, posted October 7, 2017, courtesy of Christopher Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

For decades, there have been mysterious deaths of Coho salmon. The salmon return from the Pacific Ocean each year to spawn along the West Coast. They can be found from Alaska all the way down into California. After heavy rain events each fall, fish have been turning up dead in huge numbers before they spawn. Normally, less than 1% of adult Coho die before spawning. In these mass death events, anywhere from 40% to 90% of fish can perish in affected streams. The mysterious phenomenon has been the subject of intense research for years.

Recently, scientists announced that they may have solved the mystery. There is a chemical antioxidant known as 6PPD that is used in the manufacture of tires around the world to make them last longer. As tire treads break down over time, they leave behind bits of microplastics on roads. The 6PPD in the plastic bits reacts with ozone to become another chemical: a previously unreported substance called 6PPD-quinone.

That chemical turns out to be toxic to Coho salmon. Researchers have found the presence of 6PPD-quinone in roadway water runoff samples taken from across the West Coast. Based on these observations, they believe it is likely that exposure to this chemical is the main cause of the Coho salmon population decline.

Coho salmon are a favorite of sport fishermen and have great cultural significance to many Native American tribes on the West Coast. The central California Coho population is classified as endangered and three other Coho populations are listed as threatened.

Tire industry representatives call the study results “preliminary” but say the industry is deeply committed to protecting the environment. A safe chemical substitute for 6PPD is clearly needed.

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Salmon have been dying mysteriously on the West Coast for years. Scientists think a chemical in tires may be responsible

Photo, posted November 17, 2011, courtesy of Lynn Ketchum/Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.