Antarctic giant petrels, heroes or villains?


This 29 October 2019 video says about itself:

Giant Petrels: Heroes or Villains? | Seven Worlds, One Planet | BBC Earth

Giant petrels are aggressive, fearless and aren’t afraid of some gore. But they’re also called ‘the vultures of Antarctica‘ thanks to their clean-up characteristic of feeding on carrion. So are giant petrels heroes or villains?

Antarctic marine life, video


This 27 October 2019 video says about itself:

The Enchanted World Beneath the Antarctic Ice Sheet | Seven Worlds, One Planet | BBC Earth

The Seven Worlds, One Planet crew dived beneath the surface of the Antarctic ice sheet with only a tiny bore hole for escape. Discover the wonders they found in the frozen seas.

Chinstrap penguins drive away skua egg thief


This 26 October 2019 video from the Antarctic says about itself:

Chinstrap Penguins Chase Off Daring Egg Thief | Seven Worlds, One Planet | BBC Earth

Skuas will eat penguin eggs if they get the chance, but these chinstrap penguins are having none of it! Behind the scenes from David Attenborough‘s Seven Worlds, One Planet.

Antarctic marine life recovery after dinosaurs’ extinction


This August 2016 video says about itself:

Fossil hunters want to know what life was like when dinosaurs became extinct 66 million years ago. We join an Aussie [Australian] palaeontologist on a US expedition searching for dinosaur fossils in Antarctica, the most challenging place to explore the end of their ancient world.

From the British Antarctic Survey:

Antarctic marine life recovery following the dinosaurs’ extinction

June 19, 2019

A new study shows how marine life around Antarctica returned after the extinction event that wiped out the dinosaurs.

A team led by British Antarctic Survey studied just under 3000 marine fossils collected from Antarctica to understand how life on the sea floor recovered after the Cretaceous-Paleogene (K-Pg) mass extinction 66 million years ago. They reveal it took one million years for the marine ecosystem to return to pre-extinction levels. The results are published today (19 June 2019) in the journal Palaeontology.

The K-Pg extinction wiped out around 60% of the marine species around Antarctica, and 75% of species around the world. Victims of the extinction included the dinosaurs and the ammonites. It was caused by the impact of a 10 km asteroid on the Yucatán Peninsula, Mexico, and occurred during a time period when the Earth was experiencing environmental instability from a major volcanic episode. Rapid climate change, global darkness, and the collapse of food chains affected life all over the globe.

The K-Pg extinction fundamentally changed the evolutionary history of life on Earth. Most groups of animals that dominate modern ecosystems today, such as mammals, can trace the roots of their current success back to the aftermath of this extinction event.

A team of scientists from British Antarctic Survey, the University of New Mexico and the Geological Survey of Denmark & Greenland show that in Antarctica, for over 320,000 years after the extinction, only burrowing clams and snails dominated the Antarctic sea floor environment. It then took up to one million years for the number of species to recover to pre-extinction levels.

Author Dr Rowan Whittle, a palaeontologist at British Antarctic Survey says:

“This study gives us further evidence of how rapid environmental change can affect the evolution of life. Our results show a clear link in the timing of animal recovery and the recovery of Earth systems.”

Author Dr James Witts, a palaeontologist at University of New Mexico says:

“Our discovery shows the effects of the K-Pg extinction were truly global, and that even Antarctic ecosystems, where animals were adapted to environmental changes at high latitudes like seasonal changes in light and food supply, were affected for hundreds of thousands of years after the extinction event.”

What Adélie penguins eat, study with spacecraft


This 12 December 2018 video from the USA says about itself:

2018 Fall Meeting Press Conference: Penguins! From space

The science team that led the expedition to document the supercolony of penguins on the remote Danger Islands in Antarctica will present new results from their research conducted on the expedition, including new, unpublished information on the age of the supercolony.

NASA satellite imagery of the penguins’ bright pink poop, or guano, helped the scientists first pinpoint the location of the supercolony of Adélie penguins.

In this press conference, the scientists will report new findings from the refined tools and techniques they’ve developed since the expedition to study penguins from space.

Participants: Heather Lynch, Stony Brook University, Stony Brook, New York, U.S.A.; Michael Polito, Louisiana State University, Baton Rouge, Louisiana, U.S.A.; Casey Youngflesh, University of Connecticut, Storrs, Connecticut, U.S.A.

By Sarah Zielinski, 7:00am, January 2, 2019:

Poop provides a link in determining penguin diet from space

The best way to find out what an Adélie penguin is eating is to catch it and make it regurgitate its meal. This is about as pleasant for bird and researcher as you might think. It’s also invasive, time-consuming and expensive to do on a large scale, so scientists need other ways to determine diet. Now they have one; it relies on images taken by Landsat satellites.

The satellites don’t reveal individual penguins, let alone what they are consuming underwater. What those images do show, though, is poop. Lots of it. Because Adélie penguins cluster together at a predictable rate, researchers have figured out how to count penguin colonies just from their huge poop stains. Last year, for instance, a group led by Stony Brook University ecologist Heather Lynch reported finding a supercolony of 1.5 million Adélie penguins on the Danger Islands, off the coast of the Antarctic Peninsula, from their feces.

Figuring out dietary preferences from those images is a bit more complicated — but it also starts with poop.

Casey Youngflesh is a quantitative ecologist at the University of Connecticut in Storrs. Until a few months ago, he was a graduate student in Lynch’s lab. During that time, he made several trips to the Antarctic Peninsula, visiting Adélie penguin colonies by boat from either the tip of South America or the Falkland Islands. That required crossing some of the roughest waters on the high seas, and, he says, “it can get a little bit hairy sometimes, especially on the smaller vessels.”

Timing was essential. Visit too early and the colonies wouldn’t have started to nest. (The birds spend the dark winters following the sea ice before returning to land to raise chicks during the southern summer.) Visit too late and the colonies would be a mess, with large chicks running amok and poop mixing with mud. “Everything’s a lot cleaner and neater earlier in the season”, he notes.

Youngflesh and the other researchers on these trips gathered lots of data from the penguin colonies they visited. They at times counted birds or checked on packing densities. And sometimes they gathered poop in little smell-proof bags and brought it back to the ship.

To most people, the poop looks pink. (It also stinks, as you might expect.) The guano gets its color from the carotenoids in the carapace of krill the penguins eat. But what a penguin eats can alter that color. And so those subtle changes in color can indicate what a bird has consumed.

Back on the ship, Youngflesh would take each sample and make a “poo patty.” Each patty was “kind of the size of a hamburger patty,” he says (and, from the picture he supplied, looked a bit like one, too). He’d run the patty through a spectrometer, which measures the sample’s colors across the electromagnetic spectrum, even in wavelengths like infrared and ultraviolet that the human eye can’t see. Then the patty went into a dehydrator so it could be shipped back to the lab. There, Youngflesh would measure its nitrogen-15 levels, which correlated with where in the food web the penguin had been eating, higher (fish) or lower (krill).

Once Youngflesh had collected and analyzed poop from a dozen or so colonies along the Antarctic Peninsula, he used statistics to translate the fine spectrometer data to the coarser data in the Landsat imagery. Then each pixel of an image could be connected to the dominant item on the penguin menu: fish or krill. Adélie penguins in West Antarctica tend to eat more krill, and those in East Antarctica eat more fish, Youngflesh reported December 12 at the American Geophysical Union’s fall meeting in Washington, D.C.

Scientists have done diet studies of individual penguin populations, but it’s not easy to do that frequently. The new technique will let researchers get a snapshot of the Adélie penguin diet across the Antarctic continent, year after year, looking both in the past and into the future, Youngflesh notes. Going back through the Landsat archive didn’t reveal any big changes in penguin diet, but now researchers will be able to monitor it as the region changes and provide real data to Antarctic ecosystem managers.

Youngflesh says that researchers might be able to apply this method to other seabirds, “if they’re nesting on the ground and pooping all over the place.” Someone would have to collect more samples, though, to calibrate the satellite data. And if anyone should want more granular data about how a penguin’s diet differs from bird to bird or day to day, there aren’t many good substitutes for going to the bird itself and getting it to give up its lunch.