A must read PDF to learn the latest information regarding the origin of birds:
Thursday, October 29, 2015
Wednesday, October 28, 2015
El Niño is bad news for #penguins
Dramatic changes in climate force birds to swim more than 80 miles further in search of fish
- Between 1992 and 2010, researchers fitted king penguins with trackers
- This allowed them to track their movements in the Indian Ocean
- A climate anomaly of just 1°C (34°F) can shift the limit of the polar front
- This increases how far birds swim to find fish by up to 83 miles (130km)
Weather
forecasters have been warning us to prepare for a 'monster' El Niño
this winter and now experts believe it could also have a devastating
effect on penguin numbers.
By
tracking a group of king penguins, researchers have discovered that a
climate anomaly of just 1°C (34°F) can increase how far they have to
swim in search of fish by up to 83 miles (130km).
During
the last major El Niño event in 1997, penguin populations fell by a
third and this year's event threatens to be similarly harmful.
Over a 16-year period researchers
discovered that a climate anomaly of just 1°C (34°F) can increase how
far king penguins (pictured) have to swim in search for fish by up to 83
miles (130km). During the last major El Niño event in 1997, penguin
populations fell by a third and this year's event could be similarly
devastating
Between
1992 and 2010, a group of 15 breeding penguins from the king penguin
colony of the Baie du Marin, Possession Island, Crozet were fitted with
satellite transmitters.
During summer, these penguins were tracked swimming from the Crozet Islands to forage for fish in the Antarctic polar front.
A polar front is an area where cold polar air meets warm tropical air and this boundary can measure thousands of miles long.
King
penguins, as well as other predators, get the majority of their food
from this region because the conditions are suitable for high
concentrations of zooplankton and fish.
The penguins were tracked swimming
from the Crozet Islands (represented by the orange dot) to forage for
fish in the Antarctic polar front (marked by the green lines). This
distance remained relatively stable until 1997, the year of the
strongest El Niño on record, when the southern limit shifted
dramatically
During this year, sea surface
temperatures (pictured) in the southern Indian Ocean rose 1°C (34°F)
above average and this caused the polar front to shift by around 83
miles (130 km)
The Crozet penguins (pictured) were each fitted with satellite transmitters
The
southern limit of this front can shift in response to changes in
climate, and significant climatic events such as El Niño can cause it to
move significantly.
By
following the penguins' movements, the researchers obtained a total of
124 tracks they could use to analyse climate changes and foraging
distances.
Each track corresponded to the 'at-sea movements' of a penguin during one foraging trip off the colony.
Each year, over the 16-year tracking period, the penguins were seen leaving the Crozet Islands and typically heading south.
This distance remained relatively stable until 1997, the year of the strongest El Niño on record.
During
this year, sea surface temperatures in the southern Indian Ocean rose
1°C (34°F) above average and this caused the southern limit of the polar
front to shift by around 83 miles (130 km).
This doubled the length of time the penguins were at sea and away from the safety of the group.
'During
a climatically-extreme year, a strong southward shift of the polar
front produced a doubling of the mean distance that penguins travelled
on foraging trips, coinciding with a 34 per cent decline in the
archipelago’s breeding population the following year,' explained the
researchers.
'Future
climatic scenarios predict that the polar front may shift even further
southwards, posing a potentially serious threat to the persistence of
diving predators in the region.'
The findings are published in the journal Nature Communications.
El Niño is caused by a shift in the
distribution of warm water in the Pacific Ocean around the equator. The
National Oceanic Atmospheric Administration recently issued its official
winter forecast and said 'the driver of this winter's outlook is El
Niño'. It warned this year's event (right) is likely to equal the event
of 1997 (left)
The shift in the polar front was found
to double the length of time the penguins (pictured) were at sea and
away from the safety of the group. Predictions suggest that the polar
front may shift even further southwards in the future, which would pose a
potentially serious threat to the colonies in the region
El Niño is caused by a shift in the distribution of warm water in the Pacific Ocean around the equator.
Usually
the wind blows strongly from east to west, due to the rotation of the
Earth, causing water to pile up in the western part of the Pacific.
This pulls up colder water from the deep ocean in the eastern Pacific.
However, in an El Niño the winds pushing the water get weaker and cause the warmer water to shift back towards the east.
This causes the eastern Pacific to get warmer.
But
as the ocean temperature is linked to the wind currents, this causes
the winds to grow weaker still and so the ocean grows warmer, meaning
the El Niño grows.
This
change in air and ocean currents around the equator can have a major
impact on the weather patterns around the globe by creating pressure
anomalies in the atmosphere.
The
National Oceanic Atmospheric Administration recently issued its
official winter forecast and said 'the driver of this winter's outlook
is El Nino.'
It warned that this year's El Niño is already strong and appears likely to equal the event of 1997 and 1998.
Monday, October 26, 2015
New Paper on Adélie Penguin Populations (free download as PDF)
Spatially Extensive Standardized Surveys Reveal Widespread, Multi-Decadal Increase in East Antarctic Adélie Penguin Populations
- Published: October 21, 2015
- DOI: 10.1371/journal.pone.0139877
Abstract
Seabirds are considered to be useful and practical indicators of the state of marine ecosystems because they integrate across changes in the lower trophic levels and the physical environment. Signals from this key group of species can indicate broad scale impacts or response to environmental change. Recent studies of penguin populations, the most commonly abundant Antarctic seabirds in the west Antarctic Peninsula and western Ross Sea, have demonstrated that physical changes in Antarctic marine environments have profound effects on biota at high trophic levels. Large populations of the circumpolar-breeding Adélie penguin occur in East Antarctica, but direct, standardized population data across much of this vast coastline have been more limited than in other Antarctic regions. We combine extensive new population survey data, new population estimation methods, and re-interpreted historical survey data to assess decadal-scale change in East Antarctic Adélie penguin breeding populations. We show that, in contrast to the west Antarctic Peninsula and western Ross Sea where breeding populations have decreased or shown variable trends over the last 30 years, East Antarctic regional populations have almost doubled in abundance since the 1980’s and have been increasing since the earliest counts in the 1960’s. The population changes are associated with five-year lagged changes in the physical environment, suggesting that the changing environment impacts primarily on the pre-breeding age classes. East Antarctic marine ecosystems have been subject to a number of changes over the last 50 years which may have influenced Adélie penguin population growth, including decadal-scale climate variation, an inferred mid-20th century sea-ice contraction, and early-to-mid 20th century exploitation of fish and whale populations.Tuesday, October 13, 2015
Threat to Penguins, Part II: Melting of Antarctic ice shelves set to intensify
Date:
Ice shelves are the floating extensions of the continent's massive land-based ice sheets. While the melting or breakup of floating ice shelves does not directly raise sea level, ice shelves do have a "door stop" effect: They slow the flow of ice from glaciers and ice sheets into the ocean, where it melts and raises sea levels.
"Our results illustrate just how rapidly melting in Antarctica can intensify in a warming climate," said Luke Trusel, lead author and postdoctoral scholar at Woods Hole Oceanographic Institution (WHOI).
"This has already occurred in places like the Antarctic Peninsula where we've observed warming and abrupt ice shelf collapses in the last few decades. Our model projections show that similar levels of melt may occur across coastal Antarctica near the end of this century, raising concerns about future ice shelf stability."
The study, published Oct. 12, 2015, in Nature Geoscience, was conducted by Trusel, Clark University Associate Professor of Geography Karen Frey, WHOI scientists Sarah Das and Kristopher Karnauskas, Peter Kuipers Munneke and Michiel R. van den Broeke of the Institute for Marine and Atmospheric Research Utrecht University, and Erik van Meijgaard of the Royal Netherlands Meteorological Institute.
To study how melting evolves over time and to predict future ice sheet melting along the entire Antarctic coastline, the scientists combined satellite observations of ice surface melting with climate model simulations under scenarios of intermediate and high levels of greenhouse gas emissions until the year 2100.
The results indicate a strong potential for the doubling of Antarctica-wide ice sheet surface melting by 2050, under either emissions scenario. However, between 2050 and 2100, the models reveal a significant divergence between the two scenarios. Under the high-emissions climate scenario, by 2100 ice sheet surface melting approaches or exceeds intensities associated with ice shelf collapse in the past. Under the reduced-emissions scenario, there is relatively little increase in ice sheet melting after the doubling in 2050.
"The data presented in this study clearly show that climate policy, and therefore the trajectory of greenhouse gas emissions over the coming century, have an enormous control over the future fate of surface melting of Antarctic ice shelves, which we must consider when assessing their long-term stability and potential indirect contributions to sea level rise," said Frey.
Funding for the research was provided by NASA, the Doherty Postdoctoral Scholarship Program at WHOI, the Netherlands Earth System Science Centre, the Polar Program of the Netherlands Organization of Scientific Research, and the Dutch Ministry of Infrastructure and the Environment.
- October 12, 2015
- Source:
- Woods Hole Oceanographic Institution
- Summary:
- New research projects a doubling of surface melting of Antarctic ice shelves by 2050 and that by 2100 melting may surpass intensities associated with ice shelf collapse, if greenhouse gas emissions from fossil fuel consumption continue at the present rate.
The study's lead author, Luke
Trusel, standing in front of sea ice covered in melt ponds in December
2010 outside of McMurdo Station, Antarctica.
Credit: Photo courtesy of Luke Trusel
New research published today projects a
doubling of surface melting of Antarctic ice shelves by 2050 and that
by 2100 melting may surpass intensities associated with ice shelf
collapse, if greenhouse gas emissions from fossil fuel consumption
continue at the present rate.
Ice shelves are the floating extensions of the continent's massive land-based ice sheets. While the melting or breakup of floating ice shelves does not directly raise sea level, ice shelves do have a "door stop" effect: They slow the flow of ice from glaciers and ice sheets into the ocean, where it melts and raises sea levels.
"Our results illustrate just how rapidly melting in Antarctica can intensify in a warming climate," said Luke Trusel, lead author and postdoctoral scholar at Woods Hole Oceanographic Institution (WHOI).
"This has already occurred in places like the Antarctic Peninsula where we've observed warming and abrupt ice shelf collapses in the last few decades. Our model projections show that similar levels of melt may occur across coastal Antarctica near the end of this century, raising concerns about future ice shelf stability."
The study, published Oct. 12, 2015, in Nature Geoscience, was conducted by Trusel, Clark University Associate Professor of Geography Karen Frey, WHOI scientists Sarah Das and Kristopher Karnauskas, Peter Kuipers Munneke and Michiel R. van den Broeke of the Institute for Marine and Atmospheric Research Utrecht University, and Erik van Meijgaard of the Royal Netherlands Meteorological Institute.
To study how melting evolves over time and to predict future ice sheet melting along the entire Antarctic coastline, the scientists combined satellite observations of ice surface melting with climate model simulations under scenarios of intermediate and high levels of greenhouse gas emissions until the year 2100.
The results indicate a strong potential for the doubling of Antarctica-wide ice sheet surface melting by 2050, under either emissions scenario. However, between 2050 and 2100, the models reveal a significant divergence between the two scenarios. Under the high-emissions climate scenario, by 2100 ice sheet surface melting approaches or exceeds intensities associated with ice shelf collapse in the past. Under the reduced-emissions scenario, there is relatively little increase in ice sheet melting after the doubling in 2050.
"The data presented in this study clearly show that climate policy, and therefore the trajectory of greenhouse gas emissions over the coming century, have an enormous control over the future fate of surface melting of Antarctic ice shelves, which we must consider when assessing their long-term stability and potential indirect contributions to sea level rise," said Frey.
Funding for the research was provided by NASA, the Doherty Postdoctoral Scholarship Program at WHOI, the Netherlands Earth System Science Centre, the Polar Program of the Netherlands Organization of Scientific Research, and the Dutch Ministry of Infrastructure and the Environment.
Story Source:
The above post is reprinted from materials provided by Woods Hole Oceanographic Institution. Note: Materials may be edited for content and length.
The above post is reprinted from materials provided by Woods Hole Oceanographic Institution. Note: Materials may be edited for content and length.
Journal Reference:
- Luke D. Trusel, Karen E. Frey, Sarah B. Das, Kristopher B. Karnauskas, Peter Kuipers Munneke, Erik van Meijgaard & Michiel R. van den Broeke. Divergent trajectories of Antarctic surface melt under two twenty-first-century climate scenarios. Nature Geoscience, 2015 DOI: 10.1038/ngeo2563
Woods
Hole Oceanographic Institution. "Melting of Antarctic ice shelves set
to intensify." ScienceDaily. ScienceDaily, 12 October 2015.
<www.sciencedaily.com/releases/2015/10/151012115711.htm>.
Threat to Penguins: Global marine analysis suggests food chain collapse
Date:
Published today in the journal Proceedings of the National Academy of Sciences (PNAS), marine ecologists from the University of Adelaide say the expected ocean acidification and warming is likely to produce a reduction in diversity and numbers of various key species that underpin marine ecosystems around the world.
"This 'simplification' of our oceans will have profound consequences for our current way of life, particularly for coastal populations and those that rely on oceans for food and trade," says Associate Professor Ivan Nagelkerken, Australian Research Council (ARC) Future Fellow with the University's Environment Institute.
Associate Professor Nagelkerken and fellow University of Adelaide marine ecologist Professor Sean Connell have conducted a 'meta-analysis' of the data from 632 published experiments covering tropical to artic waters, and a range of ecosystems from coral reefs, through kelp forests to open oceans.
"We know relatively little about how climate change will affect the marine environment," says Professor Connell. "Until now, there has been almost total reliance on qualitative reviews and perspectives of potential global change. Where quantitative assessments exist, they typically focus on single stressors, single ecosystems or single species.
"This analysis combines the results of all these experiments to study the combined effects of multiple stressors on whole communities, including species interactions and different measures of responses to climate change."
The researchers found that there would be "limited scope" for acclimation to warmer waters and acidification. Very few species will escape the negative effects of increasing CO2, with an expected large reduction in species diversity and abundance across the globe. One exception will be microorganisms, which are expected to increase in number and diversity.
From a total food web point of view, primary production from the smallest plankton is expected to increase in the warmer waters but this often doesn't translate into secondary production (the zooplankton and smaller fish) which shows decreased productivity under ocean acidification.
"With higher metabolic rates in the warmer water, and therefore a greater demand for food, there is a mismatch with less food available for carnivores ─ the bigger fish that fisheries industries are based around," says Associate Professor Nagelkerken. "There will be a species collapse from the top of the food chain down."
The analysis also showed that with warmer waters or increased acidification or both, there would be deleterious impacts on habitat-forming species for example coral, oysters and mussels. Any slight change in the health of habitats would have a broad impact on a wide range of species these reefs harbour.
Another finding was that acidification would lead to a decline in dimethylsulfide gas (DMS) production by ocean plankton which helps cloud formation and therefore in controlling Earth's heat exchange.
- October 12, 2015
- Source:
- University of Adelaide
- Summary:
- A world-first global analysis of marine responses to climbing human carbon dioxide emissions has painted a grim picture of future fisheries and ocean ecosystems.
Bleached coral colony, no fish.
Credit: © ead72 / Fotolia
A world-first global analysis of marine responses to climbing human CO2 emissions has painted a grim picture of future fisheries and ocean ecosystems.
Published today in the journal Proceedings of the National Academy of Sciences (PNAS), marine ecologists from the University of Adelaide say the expected ocean acidification and warming is likely to produce a reduction in diversity and numbers of various key species that underpin marine ecosystems around the world.
"This 'simplification' of our oceans will have profound consequences for our current way of life, particularly for coastal populations and those that rely on oceans for food and trade," says Associate Professor Ivan Nagelkerken, Australian Research Council (ARC) Future Fellow with the University's Environment Institute.
Associate Professor Nagelkerken and fellow University of Adelaide marine ecologist Professor Sean Connell have conducted a 'meta-analysis' of the data from 632 published experiments covering tropical to artic waters, and a range of ecosystems from coral reefs, through kelp forests to open oceans.
"We know relatively little about how climate change will affect the marine environment," says Professor Connell. "Until now, there has been almost total reliance on qualitative reviews and perspectives of potential global change. Where quantitative assessments exist, they typically focus on single stressors, single ecosystems or single species.
"This analysis combines the results of all these experiments to study the combined effects of multiple stressors on whole communities, including species interactions and different measures of responses to climate change."
The researchers found that there would be "limited scope" for acclimation to warmer waters and acidification. Very few species will escape the negative effects of increasing CO2, with an expected large reduction in species diversity and abundance across the globe. One exception will be microorganisms, which are expected to increase in number and diversity.
From a total food web point of view, primary production from the smallest plankton is expected to increase in the warmer waters but this often doesn't translate into secondary production (the zooplankton and smaller fish) which shows decreased productivity under ocean acidification.
"With higher metabolic rates in the warmer water, and therefore a greater demand for food, there is a mismatch with less food available for carnivores ─ the bigger fish that fisheries industries are based around," says Associate Professor Nagelkerken. "There will be a species collapse from the top of the food chain down."
The analysis also showed that with warmer waters or increased acidification or both, there would be deleterious impacts on habitat-forming species for example coral, oysters and mussels. Any slight change in the health of habitats would have a broad impact on a wide range of species these reefs harbour.
Another finding was that acidification would lead to a decline in dimethylsulfide gas (DMS) production by ocean plankton which helps cloud formation and therefore in controlling Earth's heat exchange.
Story Source:
The above post is reprinted from materials provided by University of Adelaide. Note: Materials may be edited for content and length.
The above post is reprinted from materials provided by University of Adelaide. Note: Materials may be edited for content and length.
Journal Reference:
- Ivan Nagelkerken and Sean D. Connell. Global alteration of ocean ecosystem functioning due to increasing human CO2 emissions. PNAS, October 12, 2015 DOI: 10.1073/pnas.1510856112
University
of Adelaide. "Global marine analysis suggests food chain collapse."
ScienceDaily. ScienceDaily, 12 October 2015.
<www.sciencedaily.com/releases/2015/10/151012181037.htm>.
Friday, October 9, 2015
This Extinct Penguin Was the Best Animal To Waddle the Earth
There
are many advantages to being alive today, but there is one
disadvantage—we missed out on seeing the best animal ever. Thirty-seven
million years ago, the oceans and land were patrolled by a 6’8” penguin.
Today,
Antarctic penguins are struggling. Thirty-seven million years ago, life
was good. The coast of the continent was home to many different species
of penguin, some of which would look familiar to us today. Others, not
so much.
One penguin in particular would make us look twice—and possibly run. Palaeeudyptes klekowskii was sized up as the result of two different finds.
Neither was a complete skeleton, but both provided multiple wing bones
and foot bones that allowed scientists to estimate the penguin’s size.
Assuming it had the same proportions as modern penguins, this extinct megapenguin was a little over six-and-a-half feet tall. Before the discovery, the largest penguin species to ever have existed was thought to be only about five feet tall, just a foot taller than the Emperor penguin. Palaeeudyptes klekowskii
would have stood out, even among the other penguins waddling around
with it in its own time. It also would have dived down lower than other
penguins, or at least stayed underwater longer.
A larger body means a
larger lung capacity, so these penguins would probably have been able to
stay under water for 40 minutes between breaths. Imagine a
basketball-player-sized penguin coming at you from out of the darkness.
Adorable.
source
Friday, October 2, 2015
Poop on a Stick Tests #Penguins’ Sense of Smell
By Elizabeth Preston |
October 2, 2015
Who doesn’t enjoy waking to a pleasant smell wafting past? Unfortunately for them, the penguins in a recent study woke up not to pancakes frying nearby, but to less appetizing aromas—for example, feces on a stick. But scientists promise the experiment taught them valuable lessons about a penguin’s capabilities. Besides, they let the birds go right back to sleep.
“Research into the sense of smell in birds has a bit of a dubious history,” says Gregory Cunningham, a biologist at St. John Fisher College. In recent decades, scientists have begun to get a better grasp on what birds can smell, but there’s still a lot to learn.
With king penguins (Aptenodytes patagonicus), researchers have focused more on sound than smell. The birds form monogamous pairs to breed; parents take turns caring for the egg or chick and foraging for food. When a penguin returns from the sea, it uses the sound of its partner’s squawk to find it among the huge breeding colony.
Penguins seem to use their sense of smell to help them hunt for fish, so it’s possible the birds also use smell to find each other. Maybe they can sniff out the colony when they’re getting close; maybe they can even recognize the individual scent of a partner. The first step toward finding out is to see how penguins react to the smell of other penguins. Do they notice the smell of penguin feces or feathers?
Cunningham and his coauthor, Francesco Bonadonna, studied a king penguin colony in the Kerguelen Islands. (Coincidentally, the scientists shared a beach with some other researchers you may have read about here, who were studying whether penguins find each other’s beaks sexy.) To test the birds’ sensitivity to smells, Cunningham and Bonadonna would use a very simple test: could the smell wake a sleeping penguin?
The researchers wrapped duct tape around the ends of metal dowels, sticky side out. Then they rolled the tape in one of three materials: ordinary sand, recently molted penguin feathers, or fresh penguin poop. Cunningham says the feathers and feces were both easily detectable to a human nose. (The feces “did not smell very good,” he notes, while the feathers had a more subtle, “perhaps musky” odor.)
On the beach, they looked for penguins that were asleep, standing with their beaks tucked under one wing. They tested 108 sleeping birds. Each time, a researcher crept up to the penguin and held one of the odor sticks about an inch beneath its beak. After 15 seconds, they scored the bird’s reaction. A penguin got a score of zero if it kept dozing, 1 if it moved its head a little or clacked its beak, 2 if it twitched, and 3 if it woke up outright.
Penguins reacted significantly more to feces or feathers than they did to sand. The bird in the video below, for example, was presented with a feces stick.
It may not be shocking that an animal can smell a blob of poop. But Cunningham says this preliminary experiment will eventually help us understand how penguins use scent to get around. He’s shown that the birds can detect the smell of other penguins; the next step will be to learn whether they use these smells to rendezvous with their colonies or partners.
“We’re taking a species that has long been thought to use primarily acoustic cues to identify each other,” Cunningham says, “and adding another layer of complexity to their umwelt, their sensory world.” Meanwhile, the animals probably wish the scientists would add a layer of something between those poop sticks and their beaks.
source
Who doesn’t enjoy waking to a pleasant smell wafting past? Unfortunately for them, the penguins in a recent study woke up not to pancakes frying nearby, but to less appetizing aromas—for example, feces on a stick. But scientists promise the experiment taught them valuable lessons about a penguin’s capabilities. Besides, they let the birds go right back to sleep.
“Research into the sense of smell in birds has a bit of a dubious history,” says Gregory Cunningham, a biologist at St. John Fisher College. In recent decades, scientists have begun to get a better grasp on what birds can smell, but there’s still a lot to learn.
With king penguins (Aptenodytes patagonicus), researchers have focused more on sound than smell. The birds form monogamous pairs to breed; parents take turns caring for the egg or chick and foraging for food. When a penguin returns from the sea, it uses the sound of its partner’s squawk to find it among the huge breeding colony.
Penguins seem to use their sense of smell to help them hunt for fish, so it’s possible the birds also use smell to find each other. Maybe they can sniff out the colony when they’re getting close; maybe they can even recognize the individual scent of a partner. The first step toward finding out is to see how penguins react to the smell of other penguins. Do they notice the smell of penguin feces or feathers?
Cunningham and his coauthor, Francesco Bonadonna, studied a king penguin colony in the Kerguelen Islands. (Coincidentally, the scientists shared a beach with some other researchers you may have read about here, who were studying whether penguins find each other’s beaks sexy.) To test the birds’ sensitivity to smells, Cunningham and Bonadonna would use a very simple test: could the smell wake a sleeping penguin?
The researchers wrapped duct tape around the ends of metal dowels, sticky side out. Then they rolled the tape in one of three materials: ordinary sand, recently molted penguin feathers, or fresh penguin poop. Cunningham says the feathers and feces were both easily detectable to a human nose. (The feces “did not smell very good,” he notes, while the feathers had a more subtle, “perhaps musky” odor.)
On the beach, they looked for penguins that were asleep, standing with their beaks tucked under one wing. They tested 108 sleeping birds. Each time, a researcher crept up to the penguin and held one of the odor sticks about an inch beneath its beak. After 15 seconds, they scored the bird’s reaction. A penguin got a score of zero if it kept dozing, 1 if it moved its head a little or clacked its beak, 2 if it twitched, and 3 if it woke up outright.
Penguins reacted significantly more to feces or feathers than they did to sand. The bird in the video below, for example, was presented with a feces stick.
It may not be shocking that an animal can smell a blob of poop. But Cunningham says this preliminary experiment will eventually help us understand how penguins use scent to get around. He’s shown that the birds can detect the smell of other penguins; the next step will be to learn whether they use these smells to rendezvous with their colonies or partners.
“We’re taking a species that has long been thought to use primarily acoustic cues to identify each other,” Cunningham says, “and adding another layer of complexity to their umwelt, their sensory world.” Meanwhile, the animals probably wish the scientists would add a layer of something between those poop sticks and their beaks.
source
Researchers struggle to understand shifts in the migratory patterns of #penguins in the SW Atlantic
Ocean Sentinels
| October 1, 2015
ELIZABETH FIEDLERIt’s an early August morning on a nearly deserted beach in southern Brazil, and 23 Magellanic penguins (Spheniscus magellanicus) are tottering toward the water. These penguins are survivors. About two months ago, birds that should have been swimming and feeding offshore started washing up on the beaches of the Brazilian state of Santa Catarina, primarily near the city of Florianopolis. More than 120 have come ashore this year, but most were too weak to survive. The birds now heading toward the Atlantic waves lapping Moçambique Beach were rehabilitated by a group of veterinarians and volunteers who stand gathered on the shore, watching their avian charges disappear into the water.
Each year around April, as the Southern Hemisphere winter approaches, the Magellanic penguins, also known as Patagonian penguins, leave their breeding grounds in southern Argentina. They migrate northward to wintering grounds in the coastal waters of northern Argentina, Uruguay, and southern Brazil in search of food. (Some southernmost breeders also head along Chile’s Pacific shores, but that route is less well studied.) It’s a monumental journey: a round-trip of up to 4,000 kilometers that coincides with the seasonal spawning of anchovies, a staple of the penguins’ diets. The birds face many challenges along the way, and some run out of strength, winding up on Brazil’s beaches in serious need of help.
Birds like these appear every year, while others continue their travels even farther north. Researchers are still trying to understand exactly why some birds end up farther from home than ever before.
These temperate penguin species demonstrate that new challenges are confronting their populations.—P. Dee Boersma,
University of Washington
Cristiane Kolesnikovas is a veterinarian with Associação R3 Animal, an NGO that does wildlife rehabilitation for the Santa Catarina State government. Sitting in her office at Parque Estadual do Rio Vermelho, the state park where the penguins are rehabilitated, Kolesnikovas says each year the penguins swim north until they find sufficient food. Most of the birds that show up here are not injured—just weak.
“Most of them are juveniles that we think cannot eat as well as the adults, so they beach,” she says. “And some are caught by nets.” But for the most part, the circumstances that lead to the penguins’ arrival on Brazilian beaches are still mysterious.
Recent years have been tough for Magellanic penguins along the Atlantic coast of South America. In 2008, more than 3,000 birds were found stranded along the coast of Brazil—almost all of them juveniles. Nearly 15 percent of the birds were smothered in oil, and about a third were dead.
Pablo García Borboroglu, a researcher at Argentina’s National Research Council and president of the Global Penguin Society, and collaborators studied what happened with the penguins in 2008 and reported their findings in a 2010 Marine Pollution Bulletin article: the penguins had strayed far north of their normal winter migration path (60:1652-57). A few nearly reached the Equator. Most of the birds that went as far as northern Brazil were juveniles. Many were dehydrated, anemic, hypothermic, and emaciated, García Borboroglu says. He notes one factor that may have contributed to the anomalous migration is that year’s unusually cold sea-surface temperatures around the time that the anchovy were spawning, which may have depleted the penguins’ key prey base.
PENGUIN
KINDERGARTEN: Veterinarian Cristiane Kolesnikovas checks on juvenile
Magellanic penguins at the Parque Estadual do Rio Vermelho the day
before some of them would be released into the wild.ELIZABETH FIEDLERGarcía Borboroglu is tracking the birds to better understand the challenges they face. He’s used satellite trackers attached to their backs and bands on their feet, but he says he is still searching for a system that can withstand months in salt water and has a suitably long battery life.
García Borboroglu says he believes climate change is causing the birds to modify their migration route, but it is difficult to know for certain. He adds that most climate–change models predict increased anomalies, such as swings in temperature, throughout Earth’s oceans.
P. Dee Boersma, a collaborator of García Borboroglu who heads the University of Washington’s Center for Penguins as Ocean Sentinels, says that temperate-zone penguins, even while pairs are incubating eggs and taking turns feeding at sea, are swimming 60 km farther north from their nests than they did a decade ago. This change likely reflects “shifts in prey in response to climate change and reductions in prey abundance caused by commercial fishing,” she says. “These temperate penguin species, marine sentinels for southern oceans, demonstrate that new challenges are confronting their populations.”
Knowing what is going on with penguins could prove useful for understanding the changing nature of marine ecosystems in a broader sense. Those changes include increases in precipitation and reductions in sea ice associated with climate warming. In a 2008 BioScience article, Boersma wrote that as “ocean samplers, penguins provide insights into patterns of regional ocean productivity and long-term climate variation” (58: 597-607). Boersma says that after more than 30 years of studying temperate penguins, her research suggests that marine systems now face “a new era of unprecedented challenges.”
source