Whooping cranes' predatory behavior key for adaptation, survival

Date: February 10, 2016

Source: University of Tennessee

The whooping crane, with its snowy white plumage and trumpeting call, is one of the most beloved American birds, and one of the most endangered. As captive-raised cranes are re-introduced in Louisiana, they are gaining a new descriptor: natural killer. 

A new study from the University of Tennessee, Knoxville, suggests Louisiana cranes are faring well thanks in part to their penchant for hunting reptiles and amphibians.

Until now, mostly anecdotal evidence existed that whooping cranes regularly hunt reptiles and amphibians. Their natural history is insufficiently known, despite years of research.

Vladimir Dinets, a UT assistant professor of psychology, observed whooping cranes while participating in a reintroduction project in Louisiana, where these birds are being released after decades of absence. Since little natural habitat remains there, the captive-raised birds have to adapt to an agricultural landscape.

Dinets' study showed that reptiles and amphibians are an important high-value food source for the reintroduced whooping cranes, particularly in spring nesting season. Previously, some observers considered reptiles and amphibians to be only occasional prey of whooping cranes.

The findings were published recently in the American Midland Naturalist.

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Penguin parents: Inability to share roles increases their vulnerability to climate change

Young penguins suffer at feeding time due to an inflexible division of parental duties

Date: February 10, 2016

Source: Springer

The fixed division of labour between crested penguin parents increases their chicks' vulnerability to food shortages made ever more common by climate change. The parents have been unable to adapt their habits to the challenges of increasingly frequent years of limited food supply and, as a result, will become further threatened by extinction. So says Kyle Morrison of Massey University and the National Institute of Water & Atmospheric Research in New Zealand, who led a study published in Springer's journal Behavioral Ecology and Sociobiology.

The main duties of all penguin parents are to provide food and to defend their offspring against predatory seabirds and other intruding penguins. While on guard duty, parents fast and do not go off to sea to feed. Most penguins avoid long fasting periods by alternating brooding and chick-provisioning duties between the sexes. However, the seven species of Eudyptespenguins (the crested penguins, including rockhopper penguins) are an exception. Males guard and fast for the first three to four weeks after eggs have hatched. During this time, females are the sole providers. During the next six weeks, chicks gather together in crèches and can be fed by both parents. During this crèche phase, both sexes may make extended multi-day trips to sea to regain weight.

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Giant flightless bird wandered the Arctic 50 million years ago

A single toe bone found on Ellesmere Island in the 1970s is described for the first time

Date: February 12, 2016

Source: University of Colorado at Boulder

It's official: There really was a giant, flightless bird with a head the size of a horse's wandering about in the winter twilight of the high Arctic some 53 million years ago.

The confirmation comes from a new study by researchers from the Chinese Academy of Sciences in Beijing and the University of Colorado Boulder that describes the first and only fossil evidence from the Arctic of a massive bird known as Gastornis. The evidence is a single fossil toe bone of the 6-foot tall, several-hundred-pound bird from Ellesmere Island above the Arctic Circle. The bone is nearly a dead ringer to fossil toe bones from the huge bird discovered in Wyoming and which date to roughly the same time.

The Gastornis (formerly Diatryma) fossil from Ellesmere Island has been discussed by paleontologists since it was collected in the 1970s and appears on a few lists of the prehistoric fauna there, said Professor Thomas Stidham of the Chinese Academy of Sciences in Beijing. But this is the first time the bone has been closely examined and described, he said. Gastornis fossils also have been found in Europe and Asia.

"We knew there were a few bird fossils from up there, but we also knew they were extremely rare," said Eberle, an associate professor in geological sciences who conducts research on fossil mammals, reptiles and fishes. In addition to the Gastornisbone from Ellesmere, another scientist reported seeing a fossil footprint there, probably from a large flightless bird, although its specific location remains unknown, Eberle said.

A paper by Stidham and Eberle appears in the most recent issue of Scientific Reports, an open access, weekly journal from the publishers of Nature.

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World's Oldest Wild Bird Just Became a Mom for the 40th Time

by Laura Geggel, Staff Writer   |   February 12, 2016 11:57am ET

The world's oldest known wild bird just added a new chick to the family — her 40th one, experts say.

The Laysan albatross (Phoebastria immutabilis), named Wisdom, is at least 65 years old but shows no signs of slowing down. Wildlife officials at the Midway Atoll National Wildlife Refuge in Hawaii saw her lay an egg on Nov. 28, 2015, and incubate it for several weeks. 

A fuzzy, gray chick cracked out of its shell on Feb. 1. But Wisdom wasn't there when the baby chick hatched: She had headed out to sea on Jan. 20, leaving her mate on nest duty. She returned just after Super Bowl Sunday (Feb. 7) with a full belly and settled down on the nest, allowing her mate to fly off to sea in search of food, officials said. 

http://www.livescience.com/53621-oldest-living-wild-bird-mother-albatross.html

Study shows that songbirds recognize sound patterns using the overall spectral shape

February 9, 2016 by Heather Zeiger

(Phys.org)—New research on how songbirds recognize a sound sequence calls into question the prevailing view that songbirds tend to rely on absolute pitch to recognize a song pattern as opposed to humans who tend to rely on relative pitch. Micah R. Bregman, Aniruddh D. Patel, and Timothy Q. Gentner from the University of California in San Diego and Tufts University demonstrate through behavioral studies that starlings recognize a song pattern by its absolute spectral shape. Their work appears in The Proceedings of the National Academy of Sciences.

Songbirds, like humans, can learn sound sequences. They share many common features with human perception of sound and the ability to learn new sounds. However, songbirds perceive sequences of sounds differently. Humans can recognize a sound sequence even if the pitch or timbre changes. For example, most people can recognize "Happy Birthday" whether it is played on an oboe or a trumpet or sung by an alto or soprano. Birds, on the other hand, would not recognize this sound sequence when variations in pitch or timbre occur.

The prevailing thought is that birds recognize song patterns based on the sound sequence's absolute pitch; however, some studies have indicated that there is more to the way birds perceive a sound sequence than pitch. To understand how birds perceive a sound sequence, Bregman, et al. devised an experiment to see how songbirds perceive tone sequences that systematically vary over time in both pitch and timbre.

First, they trained five starlings (Sturnus vulgaris) to accurately discern an ascending and descending sound sequence. The starlings were able to distinguish between the ascending and descending sound sequences with over 91% accuracy.

Read more at: 

Penguin chicks huddle up for heat, protection

Location, environment influence when gentoo penguin chicks huddle

Date: February 3, 2016

Source: PLOS

Location and environmental conditions may influence when gentoo chicks huddle in cold, wet Antarctic conditions, according to a study published February 3, 2016 in the open-access journal PLOS ONE by Caitlin Black from the University of Oxford, and colleagues.

Many penguin species form aggregations for conserving heat, providing protection, and other purposes. Scientists have observed gentoo penguins aggregating during the post-guard period, a period when the parents leave the chicks without waterproof feathers daily to go find fish, but these aggregations have never been studied over a large spatial range in the Antarctic. The authors of this study observed the gentoo penguin aggregation behavior across four study sites along a latitudinal gradient. To examine the adaptive benefit of aggregations, they observed each colony during the post-guarding period of the 2012-2013 breeding season using time-lapse cameras.

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Basai wows birders with its rare avian finds

Bagish K Jha | TNN | Feb 8, 2016, 12.23 PM IST

Gurgaon: Basai has recently been in the spotlight for all the wrong reasons, with real estate eating up most of the lake that existed in the village and acted as a magnet for migratory birds. On Sunday, it was back in the news for the right reasons, as birders from across NCR hit the ground early as part of the annual Big Bird Day. They were there till late evening, recording details of all the birds they had managed to spot.

"The event is mostly organised in February and March, as the season is right for spotting water, migratory and local birds," said Abhishek Gulshan of Delhi Bird Group, an amateur body of birders which organises the event every year, in which birders spend the day counting the number of species spotted, number of birds of each species, their habitat, etc. This year's results will be published by the group on Monday on ebird.com.

Pankaj Gutpa of Delhi Bird Group said his team spent the day at Basai and nearby areas. Among others, they spotted species like the water rail, water pipit, cinnamon bittern, Baillon's crake, Indian scops owl, Indian courser, mallard duck, ferruginous pochard, Spanish sparrow, Peregrine falcon, bar-headed goose, greylag goose, moustached warbler. Sheila Chhabra, who lead the group at Basai, said the numbers were good, while adding, "But we fear that Basai, a natural wetland, may disappear in the coming years due to heavy construction around it."

"Big Bird day is a wonderful celebration of our avian friends through the dedication of an entire day to bird watching and recording the number of species sighted in the region," said Pankaj Gupta of Delhi Bird group adding that Big Bird Day was initially started by their group as an informal event held in February and March.

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