Affectionately dubbed the “penguins from space” paper (after the Scientific American article of the same name), “An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space” made the headlines in 2012. In the study, researchers used satellite imagery to count the number of emperor penguin colonies on the coasts of Antarctica. They developed techniques for differentiating between shadows in the snow, penguin guano, and the penguins themselves. In total, about 238,000 breeding pairs were identified. According to lead author Peter Fretwell, about 595,000 individual emperor penguins were counted in this first-ever satellite survey. Read more about this study at the BBC and National Geographic.
Have you ever wondered just what penguins do with their time? Our next study, entitled “Activity Time Budget during Foraging Trips of Emperor Penguins”, may help to shed some light on a day in the life of a penguin. As the title suggests, researchers tracked and observed penguins on foraging trips in the water and on sea ice. They noted that penguins spent about 70% of their time in the water, diving to depths of over 5 meters. When outside of the water, penguins spent a majority of the time resting. The researchers suggest that resting on sea ice may provide shelter from predators such as leopard seals. For more on this study, check out this video from the supporting information, or visit NBC and The Telegraph.
We now travel from Antarctica to Argentina in search of Magellanic penguins. In “How Much is Too Much? Assessment of Prey Consumption by Magellanic Penguins in Patagonian Colonies”, researchers calculated rates of prey consumption by analyzing the number of wiggles penguins made while diving. Why count wiggles? According to researchers, Magellanic penguins wiggle – that is, undulate up and down – in pursuit of prey. When penguins wiggle during their dive, it is very likely that they have caught their prey.
This evening as you gather with your loved ones to watch the fireworks, you may wonder how to keep warm in the December chill. Do what penguins do and huddle! In the aptly named “Modeling Huddling Penguins”, researchers developed a mathematical model to study the shape and movement of huddling penguins in extreme cold. The researchers simulated a group of huddling penguins and determined wind flow (refer to the image on the left, which is Fig. 1 from the study). They then identified which penguin would be the coldest and moved that penguin downwind; the scenario was repeated under different wind patterns. The researchers found that even if individual penguins work to conserve individual body heat the group as a whole can distribute an even heat loss.
Have a happy new year! We will see you all in 2013.
Citations:
Fretwell PT, LaRue MA, Morin P, Kooyman GL, Wienecke B, et al. (2012) An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space. PLoS ONE 7(4): e33751. doi:10.1371/journal.pone.0033751
Watanabe S, Sato K, Ponganis PJ (2012) Activity Time Budget during Foraging Trips of Emperor Penguins. PLoS ONE 7(11): e50357. doi:10.1371/journal.pone.0050357
Sala JE, Wilson RP, Quintana F (2012) How Much Is Too Much? Assessment of Prey Consumption by Magellanic Penguins in Patagonian Colonies. PLoS ONE 7(12): e51487. doi:10.1371/journal.pone.0051487
Waters A, Blanchette F, Kim AD (2012) Modeling Huddling Penguins. PLoS ONE 7(11): e50277. doi:10.1371/journal.pone.0050277
Image: Emperor penguins by lin_padgham.
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