The secret life of godwits

Geolocators give new insights into nesting behavior

Date: April 20, 2020

Source: University of Groningen

To find out more about birds such as the black-tailed godwit, ecologists have been conducting long-term population studies using standardized information on reproductive behaviour -- such as dates of egg-laying or hatching and levels of chick survival. New information gathered using geolocators on godwits in the Netherlands shows that traditional observation methods can lead to inaccurate data. The study was published in the April-issue of the Journal of Avian Biology.

PhD student Mo Verhoeven from the University of Groningen used geolocators attached to the legs of black-tailed godwits to follow their migration pattern. 'These consist of a tiny chip that records light intensity every five minutes, together with the exact date and time,' explains Verhoeven. This combination allows him to determine longitude and latitude from the times of sunrise and sunset. Geolocators can collect data for up to 26 months and the information is read after removal of the chip.

Shaded periods

Geolocators are generally used to learn about where birds migrate to and when they migrate. However, for this study, Verhoeven used the geolocators in a different way. 'During the nesting season, the geolocators registered shaded periods during the day,' says Verhoeven. This happens when a bird is sitting on a nest, with its legs folded under its body. 'We were, therefore, able to determine when these birds were nesting.' This was interesting. Accurate data on nesting is difficult to obtain since every observation of a nesting bird will also disturb its behaviour.

The main revelation from Verhoeven's analysis is that the godwits in this study always started a second nest if their first nest failed. 'So far, estimates of this re-nesting varied from 20 to 45 percent,' says Verhoeven. Based on traditional observation techniques, many of these second attempts were previously thought to be first nests, or they were not discovered at all. 'During the season, our observations shifted focus from detecting nests to following the development of chicks,' explains Verhoeven. His data also mean that counting nests to estimate the breeding population is not very accurate since many birds build a second nest.

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Hummingbirds show up when tropical trees fall down

Date: April 23, 2020

Source: University of Illinois College of Agricultural, Consumer and Environmental Sciences 

When the tree fell that October in 2015, the tropical giant didn't go down alone. Hundreds of neighboring trees went with it, opening a massive 2.5-acre gap in the Panamanian rainforest.

Treefalls happen all the time, but this one just happened to occur in the exact spot where a decades-long ecological study was in progress, giving University of Illinois researchers a rare look into tropical forest dynamics.

"I've been walking around that tree for 30 years now. It was just humongous," says Jeff Brawn, Professor and Stuart L. and Nancy J. Levenick Chair in Sustainability in the Department of Natural Resources and Environmental Sciences at Illinois. "Here we are, running around on this plot for years and all of a sudden I couldn't even find my way around. We just lucked into it."

What's lucky is that Brawn and his colleagues had amassed decades of data on the bird community in that exact spot, meaning they had a clear before-and-after view of what a treefall could mean for tropical birds.

This particular gap meant hummingbirds. Lots and lots of hummingbirds.

"After the treefall, we saw a very large spike in the total number of hummingbird species," says Henry Pollock, a postdoctoral scholar working with Brawn and lead author on a study published in the Journal of Field Ornithology. "Within the previous 25 years of the study, we had only documented three or four hummingbird species, and they were usually present in low numbers. There was one species, the snowy-bellied hummingbird, which we had never captured on either of our two plots in 25 years of sampling. The year after the treefall happened, we got 16 unique individuals of this one species, and total diversity of hummingbirds more than doubled."

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Arctic wildlife uses extreme method to save energy

Date: April 28, 2020

Source: Lund University

The extreme cold, harsh environment and constant hunt for food means that Arctic animals have become specialists in saving energy. Now, researchers at Lund University in Sweden have discovered a previously unknown energy-saving method used by birds during the polar night.

Researchers from Lund University and the University of Tromsø have examined the immune system strength of the Svalbard rock ptarmigan in the Arctic. This bird lives the farthest up in the Arctic of any land bird, and the researchers have investigated how the immune response varies between winter and late spring.

"We have discovered that the birds reduce how much they spend on keeping their own immune defence system up and running during the five months of the year when it is dark around the clock, probably to save energy. Instead, they use those resources on keeping warm and looking for food. When daylight returns, their immune response is strengthened again," says Andreas Nord, researcher at Lund University.

The researchers found that when the birds become ill in mid-winter, their energy consumption drops compared to when they are healthy. However, when the birds become ill in late spring, their energy consumption increases instead.

"A weaker immune system is probably a part of all the adaptations that Arctic animals use to save energy in winter. The risk of being infected by various diseases so far north is less in winter than when it becomes warmer towards summer," says Andreas Nord.

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Birdwatchers report rare sighting of Garganey duck on Arran

12th May

By Staff Reporter

Garganey Duck Male and Female

A pair of Garganey ducks have been spotted on the Isle of Arran for only the second time.

Arran Birding, who record all sightings of unusual birds on the island, reported the sighting of a male and a female on Sunday, May 3.

They said the birds were spotted on Sliddery Shore amongst Teal, a duck more common to the area.

According to Arran Birding the last time Garganeys were seen on the island was back in May 2012.

Garganeys are native to Europe and Asia, but it’s rare to see them in the UK with most breeding pairs confined to East Anglia.

The RSPB describes the Garganey as being: “Smaller than a mallard and slightly bigger than a teal. The male is most easily recognised with a broad white stripe over the eye.”

Source

Microscopic feather features reveal fossil birds' colors and explain why cassowaries shine

MAY 13, 2020

by Field Museum

Cassowaries are big flightless birds with blue heads and dinosaur-looking feet; they look like emus that time forgot, and they're objectively terrifying. They're also, along with their ostrich and kiwi cousins, part of the bird family that split off from chickens, ducks, and songbirds 100 million years ago. In songbirds and their relatives, scientists have found that the physical make-up of feathers produce iridescent colors, but they'd never seen that mechanism in the group that cassowaries are part of—until now. In a double-whammy of a paper in Science Advances, researchers have discovered both what gives cassowary feathers their glossy black shine and what the feathers of birds that lived 52 million years ago looked like.

"A lot of times we overlook these weird flightless birds. When we're thinking about what early birds looked like, it's important to study both of these two sister lineages that would have branched from a common ancestor 80 million or so years ago," says Chad Eliason, a staff scientist at the Field Museum and the paper's first author.

"Understanding basic attributes—like how colors are generated—is something we often take for granted in living animals. Surely, we think, we must know everything there is to know? But here, we started with simple curiosity. What makes cassowaries so shiny? Chad found an underlying mechanism behind this shine that was undescribed in birds. These kinds of observations are key to understanding how color evolves and also inform how we think about extinct species," says Julia Clarke, a paleontologist at the Jackson School of Geosciences at the University of Texas at Austin and the paper's senior author. Eliason began conducting research for this paper while working with Clarke at the University of Texas as part of a larger project funded by the National Science Foundation (NSF EAR 1355292) to study how flightless birds like cassowaries have evolved their characteristic features.

In humans and other mammals, color mostly comes from pigments like melanin that are in our skin and hair. Birds' colors don't just come from pigment—some of their coloration, like the rainbow flecks on hummingbirds and the shiny, glossy black on crows, is due to the physical makeup of their feathers. The parts of their cells that produce pigment, called melanosomes, affect the feathers' color based on how light bounces off those melanosomes. Different shapes or arrays of melanosomes can create different structural colors, and so can the layers of keratin making up the birds' feathers. They can reflect a rainbow of light, and they can make the difference between dull, matte feathers and feathers with a glossy shine.

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How Satellite Tracking Is Helping Scientists Understand Cuckoos

13/05/2020

ROSAMMA THOMAS

Five cuckoos, one Oriental Cuckoo and four Common Cuckoos (they look very similar but sound different and are different species) were fitted with transmitters in June last year around the Khurkh Bird Banding Centre in Northern Mongolia. These birds take advantage of the explosion of insects in the summer in Siberia to breed. By autumn, they fly to warmer places and their long-distance flights are mostly by night. Since 2009, these birds have been on the Red List of Birds of Conservation Concern.

The transmitters, which fit as small backpacks, send signals that satellites orbiting the Earth pick up. This helps scientists trace the flight path of the birds, which migrate not in groups but often as solitary travellers. On occasion, small groups may also be found.

The project, a partnership between the Wildlife Science and Conservation Centre of Mongolia, the British Trust for Ornithology and Birding Beijing, seeks a deeper understanding of the flight of the birds, to determine the reasons for the decline in their numbers.

In the UK, in the past 20 years, cuckoo numbers have declined by over half, the website of the British Trust for Ornithology explains. The cuckoo tracking project is also an attempt to foster greater involvement of local communities in conservation.

Schoolchildren in Mongolia were encouraged to name the birds irds fitted with transmitters, all of which were male. They were named Nomad (the Oriental Cuckoo), Captain Khurkh, Namja (storyteller in Mongolian folklore), Bayan (Mongolian for ‘prosper’) and Onon (the name of a local river).

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Scientists discover why some birds live fast and die young

MAY 14, 2020

by University of Sheffield

Size, safety and parenting all have an impact on how quickly a species of bird matures, according to new research from the University of Sheffield that could help scientists to understand and predict how animals will respond to climate breakdown and the destruction of habitats.

The team of scientists has studied thousands of species of birds to understand why there is so much diversity in the length of time they take to grow from a fertilised egg to an independent adult.

The research, published in Nature Communications, is the first study to consider the importance of lifestyle and environmental factors alongside evolutionary history and body size to explain the variation.

All organisms face a trade-off between reproducing and surviving and they solve this problem in different ways. The team found that bird species with a 'live fast die young' strategy develop quicker, allowing them to maximise the number of offspring they can produce in the short time they have available.

Findings showed that birds that breed and live in safer environments with fewer predators typically took longer to develop, possibly because they can afford to spend longer in a vulnerable state.

They also found that migratory birds develop much quicker, which may ensure they are ready to return to their winter habitats at the end of the summer.

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Flamingos form firm friendships

Date: April 14, 2020

Source: University of Exeter

Flamingos form friendships that last for years, new research shows.

The five-year study reveals that, despite being highly social as part of large flocks, flamingos consistently spend time with specific close "friends."

They also avoid certain individuals, suggesting some flamingos just don't get on.

The University of Exeter study examined four flamingo species at WWT Slimbridge Wetland Centre, and found social bonds including "married" couples, same-sex friendships and even groups of three and four close friends.

"Our results indicate that flamingo societies are complex. They are formed of long-standing friendships rather than loose, random connections," said Dr Paul Rose, of the University of Exeter.

"Flamingos don't simply find a mate and spend their time with that individual.

"Some mating couples spend much of their time together, but lots of other social bonds also exist.

"We see pairs of males or females choosing to 'hang out', we see trios and quartets that are regularly together.

"Flamingos have long lives -- some of the birds in this study have been at Slimbridge since the 1960s -- and our study shows their friendships are stable over a period of years.

"It seems that -- like humans -- flamingos form social bonds for a variety of reasons, and the fact they're so long-lasting suggests they are important for survival in the wild."

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Early experiences determine how birds build their first nest

Date: May 12, 2020

Source: University of Alberta

Early life experiences of zebra finches have a big effect on the construction of their first homes, according to a new study by researchers at the University of Alberta's Faculty of Science and the University of St Andrews' School of Biology.

The study shows that the presence of an adult bird as well as the types of materials available in early adolescence influence two key aspects of first-time nest building: material preference and construction speed.

"Interestingly, we noted that the preference for different materials, differentiated by colour in our study, is shaped by the juvenile experience of this material -- but only in the presence of an adult," said Lauren Guillette, assistant professor in the Department of Psychology and project lead.

"This work is important because it debunks the long-held myth that birds build nests that look like the nest in which they hatched -- making nest-building a useful model system to experimentally test how animals learn about physical properties of the world."

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How birds evolved big brains

Brain evolution traced from tyrannosaurs to modern crows

Date: April 23, 2020

Source: Bruce Museum 

An international team of evolutionary biologists and paleontologists have reconstructed the evolution of the avian brain using a massive dataset of brain volumes from dinosaurs, extinct birds like Archaeopteryx and the Great Auk, and modern birds.

The study, published online today in the journal Current Biology, reveals that prior to the mass extinction at the end of the Cretaceous Period, birds and non-avian dinosaurs had similar relative brain sizes. After the extinction, the brain-body scaling relationship shifted dramatically as some types of birds underwent an explosive radiation to re-occupy ecological space vacated by extinct groups.

"One of the big surprises was that selection for small body size turns out to be a major factor in the evolution of large-brained birds," says Dr. Daniel Ksepka, Curator of Science at the Bruce Museum and lead author of the study. "Many successful bird families evolved proportionally large brains by shrinking down to smaller body sizes while their brain sizes stayed close to those of their larger-bodied ancestors."

In order to understand how bird brains changed, a team of 37 scientists used CT scan data to create endocasts (models of the brain based on the shape of the skull cavity) of hundreds of birds and dinosaurs, which they combined with a large existing database of brain measurements from modern birds. They then analyzed brain-body allometry: the way brain size scales with body size.

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This New Scientifically Accurate Board Game Is for the Birders ia Mark Raines

“Wingspan” features 170 unique species cards filled with real-world information, life-like illustrations

By Meilan Solly

SMITHSONIANMAG.COM

MARCH 12, 2019

“Wingspan,” an eclectic new board game that transforms players into avian enthusiasts working to attract visitors to competing wildlife preserves, boasts a level of scientific rigor typically unseen in the gaming world.

As Siobhan Roberts reports for The New York Times, creator Elizabeth Hargrave—a self-proclaimed “spreadsheet geek” and avid birder—crafted “Wingspan” with mathematical precision: Drawing on data from the Cornell Lab of Ornithology’s eBird citizen-science project and All About Birds portal, as well as Audubon’s online guide to North American birds, Hargrave made a massive spreadsheet detailing information such as habitat, wingspan, red-list status and diet. At one point, the document reached a staggering size of 596 rows by nearly 100 columns.

To turn this treasure trove of factoids into a playable gaming experience, Hargrave collaborated with Stonemaier Games. Jamey Stegmaier, co-founder and president of the game publishing company, tells Audubon magazine’s Shaymus McLaughlin that he was instantly intrigued by Hargrave’s description of “Wingspan,” explaining, “There’s something about birds that instantly captures a human desire to collect, sort, and admire.”

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Cranes make comeback in Britain's wetlands

By Roger HarrabinBBC environment analyst

22 April 2020

The graceful crane - the tallest bird in the UK - is making a comeback into Britain’s wetlands thanks to re-introduction and habitat restoration.

It was absent as a breeding bird for 400 years because of wetland drainage and widespread hunting.

Now, an estimated 200 of them are dispersed in Wales, Scotland, the Fens, Suffolk and Gloucestershire.

Their recovery has been glacially slow – in 2019 there’s thought to be just one more breeding pair than 2018.

But the RSPB says population modelling suggests that number will swell much faster soon, as fecundity of the surviving birds improves with age and second generation chicks reach breeding age.

Adult cranes stand at around 1.2m (4ft) and are fabled for their complex “display“ behaviour, where they perform bows, pirouettes and bobs.

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Birds at nature reserve coming out while we stay in

A manager at a nature reserve said staff have noticed birds behaving differently, which they have put down to a lack of visitors to the site during the lockdown period.

Martin Lester said some species which might usually "hide" were being seen more often at the National Trust's Wicken Fen reserve in Cambridgeshire.

"The species that are here... are kind of behaving in a way that we've not seen before, because there are no people on the reserve, so they're in areas we don't normally see them," he said.

"The blackbirds and robins - they're always fairly resistant to human intrusion, but some of the less robust species like the warblers, some of the birds of prey, owls... they tend to hide themselves away, but this year, because there are no people on the trails... the birds are coming much closer to where we are."

He described it as "actually quite wonderful".

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Britain's largest bird of prey spotted over Saltburn and Whitby for first time in 240 YEARS

Two of Britain's largest birds of prey seen soaring 'over people's back gardens'; they were last seen in England in 1780 before humans killed them off

Britain's largest bird of prey has been spotted over Saltburn and Whitby - for the first time in 240 years.

Two white-tailed eagles have been seen soaring "over people's back gardens" and across the North York Moors.

The stunning birds, with wing spans of up to two-and-a-half-metres, were last recorded in England in 1780, on the Isle of Wight - but were killed off illegally by humans.

A five-year programme by the Roy Dennis Wildlife Foundation and Forestry England to restore the lost species is under way.

It's hoped the birds will start to breed in the south of England. 

But it's North Yorkshire the young eagles seem to prefer - for now.

"At this stage, young white-tailed eagles are quite nomadic, exploring and learning the landscape," says Dr Tim Mackrill, from the Roy Dennis Wildlife Foundation.

"The GPS transmitters are a brilliant way of tracking them, sometimes as often as every minute.

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