Penguins are vulnerable to exposure to oil spills due to their site fidelity, aquatic lifestyle and near-surface foraging habits. Across their range, penguins have been impacted by chronic and acute oil pollution at sea. The following list includes examples of events where impacts to penguins were documented.PDF The Penguins pipeline is a 60 km PIP system designed to buckle laterally on the seabed. The pipeline has been laid in a snaked shape in order to.- Scientists have invented a remote-controlled robotic emperor penguin, which resembles an emperor penguin chick, to help them better study emperor penguins in Antarctica. Because emperor penguins are extremely shy, they tend to back away and change their natural behavior whenever scientists try to study them.
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The retrieval algorithm developed by Schwaller works by sampling the colors of rocks at known penguin colonies and then flagging the same colors in parts of Antarctica where research teams have never set foot.In the pair of images above, compare the natural-color image (top) with an image with guano stains outlined in yellow (bottom) by the algorithm. Many of these remote, tiny islands off the northern tip of the Antarctic Peninsula have rarely (or never) been surveyed because sea ice cover makes them difficult to visit.By using an automated technique that keys in on penguin guano, Lynch and Schwaller used Landsat 7 images to identify roughly 166,000 penguins on Brash Island, 23,000 on Earle Island, and 7,000 on Darwin Island that were not previously accounted for.In the Landsat 7 image above, areas with guano stains have a pinker color than exposed rock without guano. Coupled with finer-resolution commercial satellite imagery and with information collected during field expeditions, data from Landsat now feeds into an online database designed to make it easy to learn how populations are faring across Antarctica.Some of the biggest colonies Schwaller and colleague Heather Lynch of Stony Brook University have discovered with Landsat are in the Danger Islands. Not only have scientists used Landsat to find dozens of previously unknown colonies, they have become adept at using satellites to assess and track penguin populations over time. Schwaller thought the stains might be big enough for satellites to detect, thereby adding a new way to estimate penguin populations.More than 30 years and several published papers later, it is clear that Schwaller was on to something. His idea was simple: since these sea ice-dependent penguins nest in large, densely packed colonies in the same place each year, they leave behind guano stains on rocks.
They always correctly identified colonies with at least 10,000 breeding pairs. By comparing the Landsat algorithm results with field observation and with finer-resolution imagery from commercial satellites (often 1 meter by 1 meter squares), the scientists determined that they could detect colonies with fewer than 3,000 breeding pairs about half the time. The map below shows other locations along the Antarctic Peninsula where Schwaller and Lynch detected previously unreported colonies.Since the size of each pixel in a Landsat image is equivalent to a 30 meter by 30 meter square, Schwaller’s technique does not always detect small penguin colonies. Adélies need exposed, relatively flat rock to nest, which probably explains why the stains on the jagged landscape of Darwin Island are smaller than others.
There is a nice synergy between satellite-based surveys and field surveys that I expect will be the status quo for a long time.”NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. “We can plan expeditions to target colonies of high interest, and satellites have made expeditions much safer because we know so much more about what to expect. Instead, it has made fieldwork more efficient,” Lynch said. The Antarctic Peninsula lost a good deal of ice over the past three decades, while the opposite happened in East Antarctica.“We’re far from a point where satellites are going to make field work irrelevant. A recent satellite-based census of Adélies found that populations have decreased near the Antarctic Peninsula but have increased in East Antarctica.
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