{"id":614265,"date":"2026-07-31T23:41:23","date_gmt":"2026-07-31T23:41:23","guid":{"rendered":"https:\/\/www.europesays.com\/ie\/614265\/"},"modified":"2026-07-31T23:41:23","modified_gmt":"2026-07-31T23:41:23","slug":"scientists-tracked-penguin-poop-from-space-and-noticed-a-troubling-antarctic-shift","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ie\/614265\/","title":{"rendered":"Scientists Tracked Penguin Poop From Space and Noticed a Troubling Antarctic Shift"},"content":{"rendered":"

\"\"<\/a>The pinkish color of these guano-covered Ad\u00e9lie penguins on Coronation Island in Antarctica is thanks to their diet. Credit: Liam Quinn\/Flickr, CC BY-SA 2.0<\/p>\n

Luckily for Heather Lynch, Ad\u00e9lie penguins eat mostly two things: fish and krill. Krill have a distinct pink color that penguin poop retains. And penguins form colonies, meaning that together, they produce \u201cabsolutely prodigious quantities of guano,\u201d she said.<\/p>\n

To put it simply: We can see penguin poop from space.<\/p>\n

A new study, published in\u00a0Current Biology<\/a>, uses satellite imagery of Ad\u00e9lie penguin guano to track how penguin diets and populations have shifted as sea ice in Antarctica has declined. The method has \u201ctotally opened our eyes to what\u2019s going on across the continent,\u201d said\u00a0Lynch<\/a>, an ecologist at Stony Brook University and coauthor of the new study.<\/p>\n

\u201cLinking diet to sea ice dynamics and population change is a key piece in the puzzle of how environmental change will influence the Southern Ocean ecosystem,\u201d\u00a0Alexandra Strang<\/a>, a doctoral candidate at the University of Canterbury in New Zealand who was not involved in the new research, wrote in an email. Strang studies population changes in Ad\u00e9lie penguins using satellite imagery.<\/p>\n

Guano Sleuths<\/p>\n

\n

To parse out trends in Ad\u00e9lie penguin diets, Lynch and the research team first needed to determine whether satellite imagery could reliably capture actual differences in guano content and color. To do this, they analyzed the spectral signal (a quantitative measure of color) and nitrogen isotope content (an indicator of the types of prey present in guano) of 103 guano samples that had been collected from 16 breeding colonies on the Antarctic Peninsula.<\/p>\n

Next, they analyzed daytime images of Antarctica from 1984 to 2013 captured by the\u00a0Landsat program<\/a>, a joint NASA\u2013U.S. Geological Survey satellite program that has provided continuous images of Earth since 1972. The Landsat images allowed researchers to find penguin breeding colonies and their respective piles of colorful poop. Then, the team compared those images to sea ice data, also collected via satellites, from the National Snow and Ice Data Center that showed where sea ice in Antarctica is declining.<\/p>\n<\/blockquote>\n

\"\"<\/a>This Landsat satellite image of Ad\u00e9lie penguin colonies in the Danger Islands off the Antarctic Peninsula, taken on 22 January 2023, shows how penguins can color islands pink with their guano. Credit: NASA<\/p>\n

\u201cThe satellite archive is like a time machine for Antarctica, so we can look at not just what penguins are eating now, but also what they were eating all the way back to the earliest days of the Landsat satellite program,\u201d Lynch said.<\/p>\n

The researchers found that penguin colonies in West Antarctica tended to eat diets higher in krill, while colonies in East Antarctica had diets higher in fish. They also found that diet was linked to population changes: Penguin colonies with diets higher in krill were more likely to have declining populations over the long term when compared to colonies with diets higher in fish. Decreased sea ice was associated with diets higher in krill as well.<\/p>\n

Such patterns are an indicator that ecosystems in the Southern Ocean are changing in ways scientists should \u201cprobably understand better,\u201d Lynch said.<\/p>\n

Because of the fine temporal resolution of Landsat data\u2014the satellites take images of each colony every 8 days\u2014researchers were also able to identify diet patterns within years, including some that Lynch didn\u2019t expect. She\u2019d thought certain colonies would consistently be either krill specialists or fish specialists, but some colonies seemed to eat more krill in the summer than they did in either fall or spring.<\/p>\n

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\u201cThis rapid-repeat schedule of the Landsat program is really neat because it allows us to get week-to-week changes that we just otherwise wouldn\u2019t have any handle on,\u201d Lynch said.<\/p>\n

Still, why penguins are changing their diets when sea ice melts remains uncertain. It\u2019s possible that less sea ice alters fish populations, changing prey availability, but more research is needed, Lynch said. \u201cThat\u2019s a question that we will hand off to our colleagues who work in the ocean.\u201d<\/p>\n

Big Questions, Big Data<\/p>\n

Lynch said the study highlights the importance of workhorse programs like Landsat, which provide consistent information over long time periods. \u201cGetting these unbroken datasets decade after decade can be incredibly valuable, and their value plays out over time,\u201d she said. \u201cIt\u2019s not always obvious\u2014we don\u2019t know what kinds of questions we\u2019ll have 30 years from now [that satellites can help answer].\u201d<\/p>\n

Scientists are just beginning to understand the extent to which satellite imagery can be used to understand ecological changes. There is a disproportionate amount of satellite imagery of the poles compared to the rest of the globe, meaning much of what ecologists are learning about satellites\u2019 utility is happening in Antarctica. But what scientists learn there could be applied to ecosystems elsewhere in the world, Lynch said.<\/p>\n

\"\"<\/a>Casey Youngflesh, an ecologist at Clemson University, prepares penguin guano samples for analysis. Credit: Casey Youngflesh<\/p>\n

\u201cOften ecological signals are masked with lots of variability or \u2018noise\u2019 and so, to detect these ecological trends, we need long-term data,\u201d Strang wrote. \u201cWith satellite imagery, we can do this. We can access more remote locations without having to be there, whilst drawing on the locations that we do have on-the-ground data from.\u201d<\/p>\n

For Ad\u00e9lie penguins, at least, the value of satellite datasets \u201cwill accrue over time,\u201d Lynch said, continuing to help researchers answer questions about penguin diet, prey availability, and how Antarctic ecosystems are changing. For example, she wants to continue to use Landsat data to determine whether krill fishing affects penguin diets. \u201cThose are the kinds of questions we can start to ask now that we can measure what they\u2019re actually eating directly.\u201d<\/p>\n

This article originally appeared in EOS Magazine<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"The pinkish color of these guano-covered Ad\u00e9lie penguins on Coronation Island in Antarctica is thanks to their diet.…\n","protected":false},"author":2,"featured_media":614266,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[273],"tags":[259160,18,259161,19,17,89049,133,461],"class_list":["post-614265","post","type-post","status-publish","format-standard","has-post-thumbnail","category-wildlife","tag-adelie-penguins","tag-eire","tag-guano","tag-ie","tag-ireland","tag-penguins","tag-science","tag-wildlife"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/117017241272145463","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/614265","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=614265"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/614265\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/614266"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=614265"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=614265"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=614265"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}