Scientists Can Now Forecast Bird Migrations With Radar and Weather Data

By Anna Groves | September 13, 2018 4:00 pm
forecast bird migration map loop midwest birds

Scientists turned to weather predictions and radar to create continental forecast maps for particular nights. Redder colors mean more migrating birds. (Credit: Benjamin Van Doren)

For many Americans and Canadians, a telltale sign of the changing seasons is a V-shaped flock of honking Canada Geese flying overhead during their migration.

These birds get attention for being large, common and noisy. But billions of other American birds migrate each fall and spring with hardly any fanfare, making their journey at night.

The cover of darkness protects migrating songbirds — like warblers, sparrows and orioles — from hungry predators like hawks. But their journey has different challenges: tall buildings, bright lights, and other dangers from humans.

These birds travel in huge pulses when weather conditions are favorable, sometimes with hundreds of millions traveling in a single night. But before now, it was hard to predict exactly where and when these pulses would happen.

Researchers announced Thursday in Science a new way to predict daily fluctuations in the number of birds taking to the skies. They developed the tool using a combination of radar, machine learning — a type of artificial intelligence — and weather forecasts.

Fair Weather Migration

Whether birds will travel on a given night depends on the weather. They want warmer temperatures and favorable winds.

“Birds are very attuned to short-term weather cycles,” says Benjamin Van Doren, a researcher at the University of Oxford who led the study. “One night (there might be) really nothing happening, and then the next night just a deluge of birds.”

“Since migration is so pulsed in this way, we can identify the relatively small number of days that large numbers of birds are coming through, and target conservation actions like turning off lights,” says Van Doren.

Radar doesn't just measure precipitation (yellows  and  reds),  it  also  reveals  migratory  birds  taking flight (circles of  blues  and  greens).  (Credit:  Kyle  G.  Horton)

Radar doesn’t just measure precipitation (yellows and reds), it also reveals migratory birds taking flight (circles of blues and greens). (Credit: Kyle G. Horton)

Tracking Bird Migration with Radar

To study the relationship between bird activity and weather, the scientists first needed a whole lot of bird data. They turned to a bank of historical radar data.

“People have been using radar to study birds since radar was invented around World War II,” says Van Doren. “It’s become more and more advanced, and covered more and more area, and had greater and greater reach over time.

Now, scientists are finally able to fulfill a long-standing vision: tracking migration on a continental scale.

For those of us who aren’t ornithologists, we know radar best from weather forecasting. When you see the weather radar, though, meteorologists have removed the “clouds” of birds that show up during migration season.

To do the new research, the scientists first had to do the opposite: remove precipitation from the radar to look at just the birds.

Kyle Horton, postdoctoral researcher at the Cornell Lab of Ornithology and co-author on the paper, taught a computer how to do this by showing it radar images that he first manually labeled as precipitation or birds.

He then used “machine learning” to let the computer figure out on its own what characteristics were best to distinguish the two. This let him automatically remove clouds from the piles and piles of radar data, a task that would’ve been too huge to do manually.

The researchers could then use the radar data to look at birds’ response to weather fluctuations on a whole new scale. They looked at migration patterns across the entire U.S. for the past 23 spring migration seasons on a day-to-day basis.

And once they understood the patterns from the past, they were able to work on a tool to predict the future.

Forecasting the Future

“This has been 20 years in the making,” says Andrew Farnsworth, another Cornell Lab of Ornithology researcher not involved in this study.

“There’s potential for cool biology to come of it, and real application to conservation,” Farnsworth says. “The potential implications are huge.”

Farnsworth and Horton penned a New York Times op-ed earlier this week about the deadly effects of city lights on migrating birds in advance of the annual 9/11 Tribute in Light. The Tribute shoots columns of lights into the sky that trace the outlines of the Twin Towers.

Birds are attracted to lights at night, for reasons not yet understood. This results in disorientation and deaths from collisions with buildings.

The New York City memorial, which happens to coincide near peak fall migration, was once particularly devastating to passing birds. But for the past few years, researchers have teamed with officials to reduce its impact dramatically by simply shutting it off for a few minutes whenever too many birds were “entangled” in confusion in the lights.

This is exactly the sort of conservation fix that could help migrating birds passing by lit cities nationwide. With the new research, where and when these and other efforts would be most impactful can now be predicted in advance.

Farnsworth estimates that the bulk of the migration occurs over just a 10-day period. Van Horen says these numbers are something else they’ll be able to estimate more precisely with their new dataset.

“Convincing municipalities and people, at both scales, to change their behaviors is not easy,” explains Farnsworth. “But it’s such a small percent of each spring and fall when a huge percentage of these birds are moving.

“We now have a unique opportunity to really think hard about how to do this kind of dynamic conservation, which is new.”

Farnsworth, Horton, and Van Doren were all in New York City Tuesday night for the Tribute in Light. They report that the lights were shut down only twice. The first was due to a large concentration of disoriented birds; the second was due to the death of an American Redstart.

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BPA Replacements Harm Reproductive Health in Mice

By Roni Dengler | September 13, 2018 12:00 pm
lab mouse in scientists hands

Scientists discovered that the BPA-free plastic in their mouse cages was harming the animals’ fertility. (Credit: unoL/shutterstock)

Twenty years ago, Patricia Hunt, a reproductive biologist at Washington State University in Pullman, revealed bisphenol A, a chemical in plastic, caused reproductive problems in mice. Soon “BPA” became a household term and “BPA-free” water bottles and consumer packaging cropped up everywhere.

Now Hunt and her same team of scientists are back with a new study that shows the compounds that replaced BPA to make BPA-free products are just as harmful. The discovery indicates bisphenols as a group are hazardous to human health.

“Reproductive health is at risk with regard to bisphenols,” said Linda Giudice, a reproductive endocrinologist at the University of California, San Francisco, who was not involved in the new research. “This is disturbing but not unexpected,” she added. “The replacements are the same class of compounds and they have the same mechanisms of action.”
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CATEGORIZED UNDER: Health & Medicine, top posts
MORE ABOUT: sex & reproduction

Thousands of Black Holes Form Disks in the Center of the Galaxy

By Chelsea Gohd | September 13, 2018 10:35 am
black holes form in disks at the center of galaxies like our milky way

In this artistic visualization, a supermassive black hole at a galaxy’s center shoots out radiation and high-speed winds. According to a new study, supermassive black holes at a galaxy’s center are surrounded by a disk of black holes and massive stars. (Credit: NASA/JPL-Caltech)

At the center of most galaxies lie supermassive black holes. Their exceptional gravity pulls in thousands of stars and stellar mass black holes, or black holes formed when a massive star collapses due to gravity.

By simulating how objects interact near the supermassive black holes in the center of galaxies, astrophysicists from Eötvös University in Hungary have shown, in a new study, that these black holes form a thick disk around a galaxy’s supermassive black hole.
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CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: cosmology

How Your Brain Lies with Confirmation Bias

By Bill Andrews | September 13, 2018 10:03 am
(Credit: Ollyy/Shutterstock)

(Credit: Ollyy/Shutterstock)

The power of our fleshy brain to control our perceptions is well established, but it’s still hard to really believe, sometimes. It’s tempting to think of ourselves as perfect observers, passively gathering data and information. But however real reality may seem, it’s just whatever our brains our feeding us. We all have various biases that, unknown to us, color how we see and interpret information.

Confirmation bias is a particularly prominent way humans get things wrong. Make a decision, or even just hold an opinion on something, and from then on your sneaky brain will make you think any new information will support your previous choice. Whether you’re considering whom to support in the next election or what schools to apply to, confirmation bias can subtly reinforce our already-formed opinions if we’re not careful.

In a Current Biology study out today, a team of psychologists and neuroscientists laid out just how powerful confirmation bias can be, and even shed light on how the process takes place in our brains.

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MORE ABOUT: bias, perception

How Satellites Are Peering Into Public Health Issues

By Nathaniel Scharping | September 12, 2018 4:30 pm
satellite map

A view of Seattle, one of the cities included in the study, taken by satellite. (Credit: Naeblys/Shutterstock)

Scientists say they have a new way of measuring obesity — from space.

Can those jokes — it doesn’t have anything to do with individuals. Instead, researchers from the University of Washington took satellite maps of various U.S. cities and trained an AI to look for features of the neighborhoods that might be relevant to health. This included things like green spaces, housing density, gyms, fast food outlets and public transportation, and they paired this data with statistics on obesity from each location. Read More

CATEGORIZED UNDER: Health & Medicine
MORE ABOUT: obesity, public health

Scientists Draw up Plan to Colonize Mars

By Amber Jorgenson | September 12, 2018 4:20 pm
Mars research dome

An artist’s illustration of the proposed Mars base. (Credit: Claudio Leonardi/EPFL)

The idea of building a base to colonize Mars and become an interplanetary species has seen decades of talk and not a whole lot of action, but now at least there’s plan.

On September 10, researchers from the École polytechnique fédérale de Lausanne (EPFL), a Switzerland university and research center, laid out a step-by-step guide to creating a sustainable research facility on Mars. Their specific plan outlines how we would get there, set up camp and create an environment that would be habitable in the long term. By adopting this strategy, researchers could finally start planning humanity’s long-awaited trip to the Red Planet.

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Hurricane Florence Intensified Fast. We Still Don’t Understand Why Some Storms Fizzle And Others Erupt

By Anna Groves | September 12, 2018 3:00 pm
A massive swirl of clouds forms in the Atlantic Ocean around Hurricane Florence's eye. Appendages of the International Space Station are visible in the foreground.

Astronaut Ricky Arnold captured this photo of Hurricane Florence from the International Space Station on September 10, 2018. (Credit: NASA)

As Hurricane Florence careens toward the Atlantic coast, more than a million Carolina residents are evacuating while millions more are hunkering down with supplies.

Hurricane Florence intensified incredibly rapidly this week, morphing from a tropical storm to a Category 4 hurricane in less than 48 hours.

How it intensified is understood, but scientists still struggle to predict which Atlantic hurricanes will intensify quickly – or not – during their journey across the ocean.

Where a Hurricane is Born

Atlantic hurricanes originate over land in Africa as systems called Easterly Waves. After these baby storms move from east to west across the African continent, they begin their coming-of-age quest across the Atlantic.

Not all of them make it.

“It’s actually one of the biggest mysteries of atmospheric sciences,” says Rosimar Ríos-Berríos, a researcher at the National Center for Atmospheric Research. “Every year we have many, many of these systems coming off Africa, and only a few of them become hurricanes.”

In general, conditions that fuel hurricanes are well understood. When the clouds that form around low pressure systems meet light wind shear (winds that are the same speed and direction at all altitudes) and warm water temperatures, the storms pull energy from the ocean and grow in size and speed.

The more these factors align, the more energy hurricanes pick up as they cross the Atlantic. Just one condition out of place – dry air, or strong winds – and the system won’t become a hurricane.

But, says Ríos-Berríos, “even with all the conditions at the right place and time, there may be something chaotic about the system that may not allow it to become a hurricane. It is a difficult but very relevant problem.”

What happens at the cloud scale is also critical for rapid hurricane intensification, but why it happens is not well understood, says Ríos-Berríos.

She says cloud formation during hurricane intensification is a bit of a “chicken or egg” conundrum. For a system to grow into a hurricane, clouds have to accumulate around a low pressure system over the ocean where winds are rotating counter-clockwise. But these low pressure systems are caused by the accumulating, rotating clouds.

“We have a lot more to learn about rapid intensification,” she says. “It’s very likely there are more small scale processes that we don’t understand.”

The Making of a Meteorologist

Ríos-Berríos studies these processes in hopes of improving hurricane predictions.

She grew up in Puerto Rico, where she and her family lived through a number of hurricanes. These experiences inspired her career in atmospheric research.

“The most memorable for me was Hurricane Georges,” she says, “which was a Category 3 when it made landfall. Living in Puerto Rico, there was a lot of uncertainty. It was always, is it coming or not, is it coming or not? With Puerto Rico being such a small island, a small change makes a very big difference.

“I got very curious about the forecasting aspect and thought, I’m going to become a meteorologist and maybe go on TV and predict them better. Then I had a summer internship and discovered I liked doing research instead. So that’s how I got into this – with the hope of doing research that can lead to doing better predictions of hurricanes.”

Hurricane Florence Intensifies

One of the signs that Hurricane Florence was rapidly intensifying was the ring of clouds visible all around the low pressure center. This allowed the eye to form, which facilitated the rapid conversion of energy from the ocean into the hurricane.

The ocean temperatures were particularly warm – 84 degrees Fahrenheit – which allowed a particularly nasty storm to form.

It’s unknown yet how wind conditions might cause Hurricane Florence to stall over land and exacerbate damages like 2017’s Harvey did, says Ríos-Berríos. This occurs when winds from the west meet winds from the east, canceling each other out and causing the storm to stay put instead of blowing past.

A final complication that other recent hurricanes haven’t faced is the mountains in the Carolinas. When moist hurricane air hits the mountains, it will be forced to go up. When moist air rises, it turns into clouds, and leads to even more precipitation. This rain shadow effect could turn Hurricane Florence into even more of a monster than it already is.

“Water, not wind, is the leading cause of fatalities during hurricanes,” says Ríos-Berríos. “It really is a very concerning threat and should be taken very very seriously.”

CATEGORIZED UNDER: Environment, top posts
MORE ABOUT: natural disasters

Spring is Arriving Earlier, Messing With Bird Migrations

By Roni Dengler | September 12, 2018 1:30 pm
migrating whooping cranes hunt for food in water

A pair of whooping cranes look for food at Necedah National Wildlife Refuge in Wisconsin. A new study shows that migrating birds could suffer as climate change shift the onset of spring. (Credit: critterbiz/shutterstock)

Thanks to climate change, spring now comes earlier. But how much sooner the season arrives varies across the U.S. That’s according to a new study published Wednesday in the journal PLOS ONE that assessed the first appearance of leaves and flowers in nearly 500 U.S. National Wildlife Refuges over more than 100 years. 

Researchers found the irregular seasonal changes affect migratory birds’ breeding sites, an outcome that could endanger many species.

Global Travels

Hundreds of migratory birds travel thousands of miles across the U.S. each year. Many birds move from Central America, where they spend the winter, to locations across the northern U.S. to breed and raise young. The success of their international travels depends on good timing. The birds must coordinate their arrivals with spring’s appearance to ensure enough food is available to eat at their destination.

Though some birds have adjusted when they migrate, it’s still unclear whether they’ll be able to keep up with changes in food availability across such vast distances over the long-term.

Eric Waller, a physical scientist at the Western Geographic Science Center of the United States Geological Survey in Menlo Park, California, who led the new research, wanted to know how the timing of the beginning of spring has changed over the last century and whether differences might affect migratory birds.

Speeding Into Spring

So, the researchers mapped data of first leaf and first bloom appearances, indices that mark the onset of spring, across 496 national wildlife refuges in the U.S. stretching back to the beginning of the last century. They found that spring now starts earlier — with leaves budding up to 3 days sooner each decade — in 76 percent of the wildlife refuges.

When the team compared the change of spring’s arrival to North American bird flyway paths, they found spring arrived a quarter of a day earlier each decade along the Central migratory route, but nearly half a day earlier each decade along the Atlantic path. Spring also came sooner at more northern latitudes, which could impact when food is available for birds along their migratory paths. So researchers assessed how a premature spring might affect blue-winged warblers and whooping cranes, two bird species that use distinct habitats and migratory pathways.

Susceptible Species

“When considering breeding and non-breeding habitats of migratory birds — such as the whooping crane and blue-winged warbler — continental-scale shifts in the onset of spring have species- and flyway-specific ramifications,” Waller said in a statement.

Waller and colleagues found spring came nearly half a day earlier each decade at both birds’ breeding sites, but not where they spent their winters. That means they may arrive at breeding sites after insects and other grub are at their most abundant.

CATEGORIZED UNDER: Environment, top posts
MORE ABOUT: climate change

Ancient Hashtag Is Oldest Drawing Yet Discovered

By Nathaniel Scharping | September 12, 2018 12:44 pm
The ochre hashtag drawing found in Blombos Cave. (Credit: Craig Foster)

The ochre hashtag drawing found in Blombos Cave. (Credit: Craig Foster)

The hashtag is far more ancient than we think.

In a South African cave, inscribed on a flake of rock, nine lines of red ochre inscribe a familiar crosshatched pattern. The find, dated to 73,000 years ago, is the oldest abstract drawing discovered to date, and it was made by ancient Homo sapiens in the area, say researchers writing Wednesday in Nature. Read More

CATEGORIZED UNDER: Living World, top posts

Humans Share Better Than Other Primates, Shedding Light on Our Evolution

By Charles Choi | September 12, 2018 9:30 am
female bonobo sits grass social setting sharing

Bonobos, like this female in the Democratic Republic of Congo, will share food with their social groups. However, unlike humans, they wont share tools and other objects. (Credit: Sergey Uryadnikov/shutterstock)

The chimp-like apes known as bonobos are legendarily generous when it comes to sex. New findings now reveal they also share food with others, but not toys or tools. This research underscores that sharing is not unique to humans, but the breadth and flexibility of this sharing may be.

Although nature is typically seen as “red in tooth and claw,” humans are often willing to voluntarily share resources with others. And the emergence and development of this sharing likely helped play a key role in human evolution. It helped ensure that vital needs were reliably met, and this food helped feed ever-larger brains.

Yet scientists have debated whether humans are unique compared with the great apes when it comes to helping others. One argument suggests that only humans are helpful enough to share food. The other side says that although the great apes can share in specific ways, only humans are versatile enough to share both food and other items.
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CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: animals

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