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Danger Islands in Antarctica will present new results from their research conducted on the expedition, including new, unpublished information on the age of the supercolony.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.

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Humans making Antarctic birds sick


This 2013 video says about itself:

Animals in the Antarctic Ice

The wildlife of Antarctica are extremophiles, having to adapt to the dryness, low temperatures, and high exposure common in Antartica. The extreme weather of the interior contrasts to the relatively mild conditions on the Antarctic Peninsula and the Subantarctic islands, which have warmer temperatures and more liquid water. Much of the ocean around the mainland is covered by sea ice. The oceans themselves are a more stable environment for life, both in the water column and on the seabed.

From the University of Barcelona in Spain:

The fauna in the Antarctica is threatened by pathogens humans spread in polar latitudes

When the human species infects other living beings

December 10, 2018

Summary: The fauna in the Antarctica could be in danger due the pathogens humans spread in places and research stations in the southern ocean.

The new study, which detected bacteria from humans in the genus Salmonella and Campylobacter in Antarctic and Subantarctic marine birds, reveals the fragility of polar ecosystems and warns about the risk of massive deaths and extinctions of local fauna populations due pathogens.

Reverse zoonosis: when the human species infects other living beings

Explorers, whalers, scientists -and lately, tourists-, are examples of human collectives that moved to the furthest regions of the planet. Some studies have claimed for years that there had been cases of reverse zoonosis, that is, infections humans give to other living beings. Despite some previous signs, scientific studies on zoonotic agents in the Antarctic and Subantarctic areas have been fragmented. Therefore, evidence is spread and not completely convincing in this field.

The new study, published in the journal Science of the Total Environment, studies the potential transmission of bacteria from humans to marine bird populations in four areas of the Antarctic and Subantarctic ecosystems. “Chronology and potential pathways for reverse zoonosis in these ecosystems are complex and difficult to study, but it seems they can be clearly related to the proximity of the fauna to inhabited areas and the presence of research stations”, says Professor Jacob González-Solís, from the Department of Evolutionary Biology, Ecology and Environmental Sciences of the UB and IRBio.

Antibiotic-resistant bacteria in polar ecosystems

The study confirms the first evidence of reverse zoonosis related to the presence of human-origin bacteria Salmonella and Campylobacter in polar fauna. One of the warning signs was, in particular, the identification of Campylobacter strains, which are resistant to ciprofloxacin and enrofloxacin (common antibiotics in medicine and veterinary).

“Finding common Campylobacter genotypes in human species or livestock was the definite hint to prove that humans can be introducing pathogens in these regions”, says Marta Cerdà-Cuéllar, researcher at the IRTA-CReSA. “These Salmonella and Campylobacter strains, which are a common cause for infections in humans and livestock, do not usually cause death outbreaks in wild animals. However, the emerging or invasive pathogens that arrive to highly sensitive populations -such as the Antarctic and Subantarctic fauna- could have severe consequences and cause the local collapse and extinction of some populations.”

Northen and Southern Hemisphere: migrating route for marine birds and pathogens

The study shows the risk of reverse zoonosis is higher in areas that are closer to inhabited areas, such as theFalkland Islands, and probably the Tristan da Cunha archipelago. In this situation, the biological connectivity between Antarctic and Subantarctic communities through marine birds is a factor that would speed up the circulation of zoonotic agents among the ecosystems from different latitudes.

“This could be the case, for instance, of the Subantarctic Stercorarius antarcticus: a scavenger marine bird could get the pathogen and spread it from Subantarctic latitudes to the Antarctica,” says González-Solís.

Polar areas: not all the biodiversity is protected

The Antarctic Treaty protocol on Environmental Protection sets a series of principles that can be applied to human activity in Antarctica to reduce the human footprint in the white continent. However, some Subantarctic areas -which are also the habitat of birds such as the brown skua or the giant petrel– are not protected by the protecting regulation and could become the entrance for pathogen agents in polar ecosystems.

“Our results show it is easier for humans to introduce pathogen agents in the pristine areas in the Antarctica. As a result, pathogens entering the furthest ecosystems in the Southern Hemisphere could be a serious threat for the future of wildlife. Therefore, it is essential to adopt biosecurity measures to limit the human impacts in the Antarctica,” notes Jacob González-Solís.

Macaroni penguins video


This video says about itself:

Macaroni Penguins Swim, Surf, and Dodge Seals to Survive – Ep. 2 | Wildlife: Resurrection Island

11 October 2018

What macaroni penguins lack in size, they make up for in sass. Life in the Antarctic doesn’t come easy for these bright yellow-crowned bundles of attitude. In this episode, Bertie joins them in the freezing ocean to swim with the adults in crashing waves. Bertie also witnesses an incredibly rare predatory event that shows how these penguins must use all their boldness to survive.

Antarctic fur seals video


This video says about itself:

4 October 2018

It’s a life of extremes for Antarctic fur seals. Bulls fight to the death for breeding rights, while seal moms work to raise their adorable pups. And National Geographic wildlife filmmaker Bertie Gregory was there to capture it all.

Antarctic crustaceans-sea snails relationship


This video says about itself:

10 September 2018

Pteropod mollusks such as Clione and Spongiobranchaea produce chemical compounds that are known to deter other organisms and prevend the pteropods from being eaten. This molecule is called pteroenone a ketone that deters many predators such as icefish.

Hyperiid amphipods are common prey of icefishes, other fish and seabirds of the Southern Ocean.

To protect themselves, some, called Hyperiella, have evolved the habit of abducting pteropods, and carrying them around on their back. It was shown that fish catching such a tandem, immediately release it.

From the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Germany:

‘Kidnapping’ in the Antarctic animal world?

A puzzling relationship between amphipods and pteropods

September 10, 2018

Pteropods or sea snails, also called sea angels, produce chemical deterrents to ward off predators, and some species of amphipods take advantage of this by carrying pteropods piggyback to gain protection from their voracious predators. There is no recognisable benefit for the pteropod. On the contrary they starve: captured between the amphipod’s legs they are unable to feed. Biologists working with Dr Charlotte Havermans at the Alfred Wegener Institute have investigated this phenomenon as part of a cooperation project with the University of Bremen. In an article in the journal Marine Biodiversity, they talk about kidnapping and explain the potential advantages of this association for both the host and its passenger.

Amphipods of the suborder Hyperiidea are popular prey for fish and sea birds. They play an important role in the Southern Ocean food web, which is why biologist Dr Charlotte Havermans is investigating the distribution, abundance and ecological role of various species of amphipods. To do so, she is taking samples on board the Research Vessel Polarstern from the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI). She works at the University of Bremen’s working group Marine Zoology. The project is funded by the DFG (German Research Foundation) in the Priority Programme on Antarctic Research.

During a Polarstern expedition that took place in the austral summer from 2016 to February 2017, she made an extraordinary discovery: “A few of the amphipods carried something unusual on their backs. On closer inspection I realised that they were carrying pteropods piggyback,” reports the biologist. A literature search revealed that US researchers had already described this behaviour back in 1990 — although only for the high-Antarctic coastal waters and not for the open Southern Ocean where the ship was underway.

“We were wondering whether these tandems occur as frequently in the open ocean as in coastal waters — and whether both animals benefit from the relationship,” explains Charlotte Havermans. In the coastal areas of the McMurdo Sound, most of the amphipods studied carried a pteropod rucksack. Subsequent genetic and morphological investigations provided new insights. Previously, such tandems were completely unknown for the open, ice-free waters of Southern Ocean, and now the biologists have discovered this behaviour in two species: the amphipod species Hyperiella dilatata carried a type of pteropod known as Clione limacina antarctica, while the crustacean Hyperiella antarctica was associated with the pteropod Spongiobranchaea australis. Our sample size was too small to say without doubt whether these are species-specific pairs, where only a certain amphipod carries a certain pteropod species. During the expedition along the Polar Front to the eastern Weddell Sea, the AWI biologist’s team found only four such tandems.

The research team’s findings regarding the benefits for the animals are very exciting. Behavioural observations of the free-living pteropods show that cod icefishes and other predators are deterred by the chemicals the gastropods produce. When amphipods take pteropods “hostage”, they are not affected by their poison. Icefishes quickly learn that amphipods with rucksacks are not tasteful and so avoid those with a pteropod on their back.

Because the conditions in the open Southern Ocean are different to those in coastal ecosystems, several open questions remain: whether or not predatory squid and lanternfish, commonly found in the area, are also deterred by the chemicals has not yet been investigated. It is also still unclear to which extent the pteropod benefits from saving energy by being carried by its host. The researchers observed that the amphipod uses two pairs of legs to keep the gastropod on their back so that they are completely unable to actively hunt for suitable food where it is available. “On the basis of our current understanding, I would say that the amphipods kidnap the pteropods,” sums up Charlotte Havermans with a wink.

The biggest lesson the authors draw from their discovery: “We are probably overlooking numerous such associations between species, because they are no longer visible after net sampling.” Unlike shelled gastropods and crustaceans, which remain relatively intact, jellyfish and other delicate animals are crushed in the nets. “In the future we will hopefully be able to use suitable underwater technologies with high-definition cameras to investigate even the smallest life forms in their habitat. This will provide insights into the numerous exciting mysteries of interspecific interactions, which have so far remained hidden for biologists — but which undoubtedly play an important role in predator-prey relationships in the ocean.”

Amphipods of the species Gammarus roeselii guard their chosen mates, often carrying them with them for days and defending them against potential rivals. This behavior requires a lot of time and energy, so that the males make their choice with care. Scientists at Goethe University have now investigated under which circumstances males are prepared to revise their decision: here.