The pinkish orangey hues of Antarctica’s Danger Islands aren’t due to minerals in the rocks or lichens covering them. Instead, the color comes from the islands’ iconic black and white inhabitants.
南极洲危险岛屿的粉橙色调并不是由于岩石中的矿物质或覆盖它们的地衣造成的。相反，颜色来自岛上标志性的黑白居民。
Dense colonies of Adélie penguins on Antarctica’s islands and coasts produce large quantities of guano, extensive enough to be seen in satellite images. The color of the droppings can even provide clues into the penguins’ diet, since krill tints the guano pink, giving researchers a unique way to monitor penguin populations.
南极洲岛屿和海岸上密集的阿德利企鹅群产生了大量的鸟粪，其数量足以在卫星图像中看到。粪便的颜色甚至可以为企鹅的饮食提供线索，因为磷虾会使鸟粪呈粉红色，这为研究人员提供了监测企鹅种群的独特方法。
Analyzing three decades of Landsat images, scientists found that Adélie penguin diets vary around the Antarctic continent and are tied to sea ice conditions. In areas with less sea ice, the penguins have a krill-rich diet; in areas with more sea ice, they eat more fish, which is associated with healthier long-term population trends.
通过分析三十年的陆地卫星图像，科学家发现南极大陆各地的阿德利企鹅饮食各不相同，并且与海冰条件有关。在海冰较少的地区，企鹅的饮食富含磷虾。在海冰较多的地区，他们吃更多的鱼，这与健康的长期人口趋势有关。
“Sea ice is such a hugely important factor in the Antarctic marine environment,” said Casey Youngflesh, an assistant professor at Clemson University in South Carolina who led the new study . “The structure of the region’s food web is changing in response.”
“海冰是南极海洋环境中非常重要的因素，”领导这项新研究的南卡罗来纳州克莱姆森大学助理教授凯西·扬弗莱什说。 “该地区食物网的结构正在发生变化。”
Adélie penguin colonies might be remote and often inaccessible, but the stark and treeless Antarctic environment provides a rare opportunity to study the entire population from space, Youngflesh said.
扬弗莱什说，阿德利企鹅的栖息地可能地处偏远，而且往往难以到达，但南极洲荒凉无树的环境为从太空研究整个企鹅种群提供了难得的机会。
Previous research identified colonies based on satellite images of guano stains on rocky shores. Youngflesh and his colleagues visited the colonies to collect and analyze guano samples, allowing them to link specific color spectra observed by satellites to the balance of krill and fish in penguin diets .
先前的研究根据岩石海岸上鸟粪污渍的卫星图像识别了菌落。 Youngflesh 和他的同事参观了这些栖息地，收集并分析了鸟粪样本，使他们能够将卫星观察到的特定色谱与企鹅饮食中磷虾和鱼类的平衡联系起来。
Now, surveying more than 100 sites around the perimeter of Antarctica with Landsat images captured between 1984 and 2013, the scientists have connected penguin diets to the surrounding sea ice conditions during the breeding and nesting seasons.
现在，科学家们利用 1984 年至 2013 年间拍摄的陆地卫星图像对南极洲周边的 100 多个地点进行了调查，将企鹅的饮食与繁殖和筑巢季节周围的海冰条件联系起来。
Between November and February, colonies around the Antarctic Peninsula and West Antarctica, where temperatures were warmer and sea ice sparser, favored a krill-based diet. In East Antarctica, where sea ice cover was more extensive, colonies feasted on more fish—a higher-quality food resource and one that leads to better chick growth and survival . A given colony’s diet also changed year to year with shifting sea ice conditions.
11 月至 2 月期间，南极半岛和西南极洲周围的栖息地气温升高，海冰稀疏，因此偏爱以磷虾为主的饮食。在东南极洲，海冰覆盖范围更广，群体可以吃更多的鱼——这是一种更高质量的食物资源，可以促进雏鸟更好的生长和生存。随着海冰条件的变化，特定群体的饮食也逐年变化。
Antarctic sea ice was relatively stable, or even increased in some regions, during the years of the study. However, since 2013 Antarctic sea ice has reached record lows, with decreasing sea ice predicted for the future. That could lead to Adélie penguins leaning more heavily on krill, Youngflesh said. But the demand for krill is increasing, he noted, due to fishing and rebounding populations of other predators like seals and whales.
在研究期间，南极海冰相对稳定，某些地区甚至有所增加。然而，自 2013 年以来，南极海冰已达到历史最低水平，预计未来海冰会减少。杨弗莱什说，这可能会导致阿德利企鹅更加依赖磷虾。但他指出，由于捕捞活动以及海豹和鲸鱼等其他捕食者数量的回升，对磷虾的需求正在增加。
The researchers are now developing computer models to use Landsat 8 and Landsat 9 data to continue tracking penguin diet and how the population responds to environmental change.
研究人员目前正在开发计算机模型，以使用 Landsat 8 和 Landsat 9 数据继续追踪企鹅的饮食以及企鹅种群对环境变化的反应。
NASA Earth Observatory image by Michala Garrison, using Landsat data from the U.S. Geological Survey . Drone image by Thomas Sayre-McCord (Woods Hole Oceanographic Institution/MIT). Story by Kate Ramsayer.
NASA 地球观测站图像，由 Michala Garrison 拍摄，使用美国地质调查局的陆地卫星数据。无人机图像由 Thomas Sayre-McCord（伍兹霍尔海洋研究所/麻省理工学院）拍摄。凯特·拉姆齐尔的故事。