King penguin with chick.
Three squawks for conservation! After New Zealand businessman Joseph Hatch boiled down 3 million Macquarie Island king penguins for their blubber, public outrage helped make the island a wildlife sanctuary in 1933. The king penguins then flourished undisturbed, growing from the decimated population of 3,400 to half a million today. Those raw numbers look good, but to gauge the population’s viability, scientists needed to find out a little more. A new study has found that the population has also recovered to pre-slaughter levels of genetic diversity, just 80 years after their near-extinction.
Population bottlenecks like the one caused by Hatch’s steam digester mean not only fewer individuals but also less diversity in the gene pool. This makes it difficult for the population to adapt to any stresses—a disease, for example, that can wipe out the remaining population if everyone has the same immune system.
To compare pre- and post-bottleneck genetic diversity, the researchers sequenced DNA from 1,000-year-old penguin bones on the island. The ancient DNA samples had similar levels of diversity as modern samples from the foot of living penguins. The researchers were surprised by how the population had recovered and saw this as a testament to conservation efforts.
What’s the News: After running aground last week on a remote island off the coast of South Africa, a freighter has leaked over 800 tons of fuel oil, coating an estimated 20,000 already-endangered penguins. “The scene at Nightingale [Island] is dreadful as there is an oil slick around the entire island,” said Tristan Conservation Officer Trevor Glass said in a statement. But even worse, authorities fear that the rats from the soybean-toting ship will swim to the island and destroy the bird population.
What’s the Context:
The Future Holds: Though a salvage tug left Cape Town, South Africa, last Thursday, the earliest it will arrive to help remove fuel is this Wednesday. With little to salvage, authorities say that cleanup is now the main task at hand. As Jay Holcomb, the director emeritus of the International Bird Rescue Research Center, told the New York Times, “Many of the birds have been oiled for over a week, which limits their chances of survival.”
Image: Wikimedia Commons / Arjan Haverkamp
Up in the sky, under the sea, deep inside an animal society—researchers can’t go these places themselves, so they attach tracking devices to wildlife in order to gather the data. But are these gizmos invisible to the creatures themselves, and can they go about their lives the same way they would if they didn’t have a tracker stuck on their fin or wing? Or do some of these electronic devices interfere with the animals’ ways of life, and therefore send back bad data to the scientists?
This week there’s a new entry into this long-running debate, regarding one of the most-tracked animals in the world: the king penguin of Antarctica. A study published in Nature that tracked 100 penguins found that those wearing flipper bands lived different lives than those without, and less successful ones to boot.
In terms of survival, banded penguins had a 16 44 percent lower rate [survival rate dropped from .36 to .20, a drop of 16 percentage points, or 44 percent] over the entire 10 years, but there is a breakpoint at 4.5 years. In the first 4.5 years, banded penguins actually had a 30 percent higher mortality rate. After that, the difference in mortality between banded and unbanded birds levels off. The authors propose that flipper-banding acts as an artificial selector for the strongest penguins, creating a bias in data collected from banded birds. Over the decade, banded birds were less successful in breeding. Banded penguins produced a total of 47 chicks, while unbanded penguins had 80 chicks. [Ars Technica]
This study presents a practical problem: Studying the effects of clipped-on tracking tags means your control group must be free of them, but you have to track the group without the flipper bands somehow. So Yvon Le Maho’s team implanted small, newer-style tags that lie under the skin on all the penguins in their study. That way they could give half of the birds a dummy tracking tag clipped on the fin to see if the equipment itself changes their behavior.
From Ed Yong:
All modern penguins wear a suit of black feathers, but prehistoric members of the group didn’t go for the dinner jacket look. A newly discovered penguin, known as Inkayacu, was dressed in grey and reddish-brown hues.
It is neither the oldest nor the largest penguin fossil, it doesn’t hail from a new part of the world, and it provides few clues about the group’s evolution. However, it does have one stand-out feature that probably secured its unveiling in the pages of Science – its feathers.
Read about Inkayacu‘s magnificently preserved fossil feathers and what they tell us about this prehistoric bird at Not Exactly Rocket Science. Ed also has the artists’ renderings of what this powerful penguin may have looked like.
80beats: What Color Were Feathered Dinosaurs and Prehistoric Birds?
80beats: Emperor Penguins May Be Marching to Extinction by 2100
80beats: Researchers Use Feather “Fingerprints” to Track Penguins
Discoblog: The Mystery of the Macaroni Penguin and the Bad Egg
Discoblog: To Track Penguins, Scientists Use High-Tech Satellite Images of…Droppings
Image: Science / AAAS
When a heterosexual Humboldt penguin couple rejected their unhatched egg this spring, zookeepers at Germany’s Bremerhaven Zoo found a happy home for the abandoned egg in the nest of gay penguin pair, Z and Vielpunkt. “Another couple threw the egg out of their batch,” the zoo’s vet said in a statement. “We picked it up and put it in the nest of the gay penguins” [The Advocate]. The couple then incubated the egg for more than a month before hatching a healthy chick that is now about four weeks old.
Z and Vielpunkt have been caring for the chick just as a heterosexual penguin couple would, say animal experts. They’ve been taking care of their chick around the clock; it’s still too young to feed itself, so the dads feed him fish mash [Los Angeles Times]. But the pair is not the first same-sex penguin couple to raise a child: a pair at Central Park Zoo in New York also hatched an egg, but only after they tried to incubate a rock until they were given an abandoned egg. Another male penguin couple were removed from their colony in a Chinese zoo last year when they repeatedly tried to steal eggs from male-and-female pairs. (In a rather ingenious move, they actually replaced the eggs they were stealing with rocks.) [Los Angeles Times]
The predicted loss of sea ice around Antarctica over the next century may doom one of the celebrities of the animal world to extinction. Emperor penguins, the species of these aquatic flightless birds featured in the Oscar-winning 2005 documentary “March of the Penguins,” breed on Antarctic sea ice and dive from the sea ice to feed on krill, fish and squid [Reuters]. In a new study, researchers examined the Intergovernmental Panel on Climate Change’s (IPCC) projections on how global warming will alter sea ice coverage around Antarctica, and say the models don’t auger well for the emperor penguins.
The researchers combined ten different climate projections with a “population dynamics” model describing the mating patterns and breeding success of emperor penguins. The model has been honed using 43 years’ worth of observations of an emperor colony in Antarctica’s Terre Adelie…. They then ran 1,000 simulations of penguin population growth or decline under each of those 10 climate scenarios [BBC News]. The results predicted that the 6,000 breeding pairs in Terre Adelie could be reduced to 400 pairs by 2100. Researchers say this 95 percent decline qualifies as a “quasi-extinction,” as the colony’s tiny remaining population would be vulnerable to diseases and genetic defects. They also say that the possible demise of the Terre Adelie colony could indicate the fate of the entire species (about 200,000 breeding pairs currently live in 40 colonies around Antarctica).
The cats ate the birds until the humans killed the cats, but now the rabbits are out of control.
That’s the sad state of affairs on Macquarie Island, an island near Antarctica that was declared a world heritage site in 1997 due to its status as the sole breeding ground for the royal penguin. For decades researchers have attempted to get rid of the invasive species that have altered the island’s ecological balance, but a new study notes that the latest effort, an all-out push to eradicate feral cats, has had the unintended consequence of allowing a boom in the rabbit population. Those rabbits have quickly denuded the landscape of its vegetation, researchers say.
Things began to go wrong on Macquarie Island … soon after it was discovered in 1810. The island’s fur seals, elephant seals and penguins were killed for fur and blubber, but it was the rats and mice that jumped from the sealing ships that started the problem. Cats were quickly introduced to keep the rodents from precious food stores. Rabbits followed some 60 years later, as part of a tradition to leave the animals on islands to give shipwrecked sailors something to eat [The Guardian]. The invasive species all thrived to the detriment of local species, and by the 1970s biologists were concerned enough to introduce a rabbit-killing disease called myxomatosis, which thinned the rabbit herds considerably. However, that left the cats with less available prey and caused them to begin hunting the island’s native burrowing birds.
Six penguin species will receive “threatened” status and one will receive “endangered” status under the Endangered Species Act, the U.S. federal government announced today. But to the disappointment of wildlife advocates, three other penguin species including the famous emperor penguin (featured in the movie “Happy Feet”) were denied protection under the act. “There are certainly issues with those species, but we did not believe at this time that the populations were reduced or that there were significant threats to lead us to make a determination that they are threatened with extinction,” said Kenneth Stansell, deputy director of the Fish and Wildlife Service [AP], the government agency responsible for the decision.
The “threatened” species include the yellow-eyed penguin, white-flippered penguin, Fiordland crested penguin, Humboldt penguin, erect-crested penguin, and some populations of southern rockhoppers; the “endangered” species is the African penguin. The birds’ habitats range from Antarctica to Peru to South Africa. None of the species are native to American soil, so their new status will have little direct bearing on U.S. policy. But listing the penguins under the act will raise awareness about the species and could give the U.S. leverage in international negotiations to protect them from fishing, habitat loss, development and other threats [AP]. These species will join the polar bear, which was recognized as “threatened” earlier this year, as some of the first species to be officially protected because of threats from global warming.
This summer, hundreds of Magellanic penguins washed ashore on Brazilian beaches, almost 2,000 miles away from their home in Patagonia. While a few penguins are typically discovered on Brazil’s coast each summer, scientists have been perplexed and worried over the mysteriously high number of drifters this year, and say they still don’t have an answer to what brought the birds so far north. In response to the crisis, an animal rescue group staged a dramatic air lift to bring the birds back home.
Like some maritime dust-bowl migration, more than 1,000 of these penguins have floated ashore in Brazil, nearly as far north as the equator. By the time their webbed feet touch sand, many are gaunt and exhausted, often having lost three-quarters of their body weight. Even more have died. “This year is completely anomalous,” said Lauro Barcellos, 51, an oceanographer who founded a rehabilitation center for penguins in southern Brazil. “. . . I’ve worked in this field for 35 years, and I have never seen anything like this” [Washington Post].
Researchers are about to get to know the 20,000 African penguins that live on Robben Island, South Africa in intimate detail, down to the last feather. A new computer program will use pictures of the penguins going about their daily business to identify each individual based on the distinct pattern of black spots on its belly. Each bird’s markings are as unique as a human fingerprint, researchers say.
Previously, researchers had to clip metal ID tags onto the penguins if they wanted to keep track of them, but that system was less than ideal. This new biometric solution has the advantage over tags as it can operate without the birds having to be caught, which greatly reduces stress on penguin and scientist. “These penguins are vicious, nasty things that bite and scratch. They have very sharp beaks. I do love them but, by God, they can hurt,” said Professor Peter Barham, of Bristol University…. “It’s no fun trying to get tags on them” [Telegraph].