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The science behind a bird fallout…there’s an app for that!!!

Birding the Sioux Falls area in April and the first half of May was…sloooooooooooooowwwww. With the late cold weather and snow, and continued wet spring precipitation, there was certainly plenty of water around (and there still is). But shorebirds were very slow all spring near Sioux Falls (perhaps just spread out?). Sparrow migration was utterly spectacular in April, but other songbirds? Once the sparrows left, it seemed like there weren’t any other songbirds filling the void. Certainly not warblers, which were few and far between for much of May. With the South Dakota Ornithologist’s Union (SDOU) meeting in Brandon on May 17-19, and with an incredibly wet forecast, the prognosis for good birding wasn’t great.

And then a funny thing happened…songbird migration ended up being utterly spectacular that weekend. The birds seemed to have arrived overnight, with warblers galore, and plenty of other songbirds as well. I personally had a 20-warbler day that Saturday (the 18th), and that’s with me whiffing on a few species that others saw in the area. It was one of the best, if not the best, warbler and songbird days I’ve had here in the 20 years I’ve been birding.

So what happened? As a scientist, I say LET’S CHECK THE SCIENCE behind it! You know how they say “There’s an app for that?” Well there’s also typically a scientific explanation behind…everything, if you look hard enough. That’s certainly true in this case.

For one, let’s check the weather radar for the overnight period from Friday, May 17th through Saturday May 18th. The weather that Friday was cloudy and rainy, driven by a low pressure system and a slowly moving front moving northeastward out of Nebraska. With the system predicted to generally stall over our area for the weekend, the forecast was bleak.

May 17th, 2019 - Weather Map
Weather map on 6:00AM (CST) on Friday, May 17th, showing a stalled to slowly moving stationary front just to our south. The forecast was for the low pressure system in Colorado to slowly move northeastward, bring showers and thunderstorms to the region for Friday night and into the weekend.

The weather system did move northeasterly through the afternoon and evening, triggering storms both along the trailing warm front to the south through Nebraska and Kansas, as well as more unsettled weather wrapping around the low pressure system. Moderate to strong northeasterly winds were found behind the low pressure system, but in front of the low were southerly and southeasterly winds…including in the area around Sioux Falls. It took until daybreak for the low pressure system to reach the Sioux Falls area, basically sitting directly over the region. But from the previous evening through daybreak on May 18th, an area from Sioux Falls, southward into extreme eastern Nebraska and all of Iowa and Minnesota were subject to south and southeasterly winds.

Surface weather map at 6:00 AM CST, showing the low sitting almost directly over Sioux Falls. But all night long, the counter-clockwise winds around the low funneled southerly and southeasterly winds through an area from far eastern South Dakota, and eastward into Iowa and Minnesota.

Given how slow the migration had been all spring long, the birds had to be…somewhere. But where? How could science have explained the fallout of warblers and other birds that weekend? The weather map and the southeasterly winds provide one clue, but the other is provided by weather radar itself. Since the 1950s, it’s been understood that weather radar could potentially identify features in the sky other than the weather…and that includes birds. There’s even a term for it now…Radar Aeroecology. A 1956 paper by Bonham and Blake discussed the radar echoes provided by both birds and flying insects. While research continued in the decades since, it’s only recently that the information has been made available for a birder’s benefit.

The animated map below shows national-scale radar returns for the night of May 17th. The advancing low and front, and associated precipitation, can be seen as it moves out of Colorado, through Nebraska and into South Dakota. But what of the radar returns in the eastern half of the country? Those are birds…birds taking flight just after sunset to resume their spring migration northward. You can identify the “bloom” around each radar location shortly after sunset, with the blooms appearing east to west as the sun sets. Where are the heaviest migration “blooms”? Look at the radars lighting up after sunset in the Midwest…St. Louis…Des Moines…other radars in Missouri, Illinois, and Iowa depicting heavy densities of birds taking flight.

Radar loop from approximately 6:00 PM (CST) Friday, May 17th, 2019 through 6:00 AM Saturday, May 18th, 2019. The areas south and east of Sioux Falls show a clear, very strong signal representing heavy migration of birds taking flight that evening.

But how can we translate those radar echos to where the birds are moving? In recent years, Cornell University, in partnership with multiple academic institutions, have developed “BirdCast“. They have developed algorithms that use weather radar returns to quantify the density of birds, while using short-term weather forecasts to project likely movements. The resultant “BirdCast” provides a 1- to 3-day look on likely bird migration hotspots.

The animated map below provides a depiction of estimated bird migration traffic that night. Ahead of the advancing front, southerly and southeasterly winds were favorable for migration, particularly as large densities of birds were already stacked up from the previous days and weeks. Sioux Falls was on the western edge of this migration hotspot, a beneficiary of favorable weather patterns bringing in birds from Missouri, Iowa, and Minnesota.

Birdcast depiction of migration traffic rate (bird density) and directional movements, from about 6:00 pm Friday, May 17th, through 6:00 AM Saturday, May 18th. with northerly winds and lower bird densities in the western Great Plains, very little bird movement is noted. However, ahead of the advancing front, extremely high migration densities are noted from Missouri, Illinois, and Iowa radar sites, with southeasterly winds pushing them northwestward…towards Sioux Falls. The solid lines represent the advancing sunset (red) and sunrise (yellow).

The map below depicts the situation that occurred throughout much of the first half of May. Prevailing weather patterns and storms, along with the cool weather, kept birds stacked up to our south and east, with a very slow spring migration to this point in South Dakota. The week prior to the big Sioux Falls fallout, birds were so far south that the Houston area birders declared a “Lights Out” period from May 9th-12th to avoid confusing the mass of migrating birds. But they had a long ways to go to get to South Dakota.

Houston Audubon "Lights Out" for May 9-12
Image from the Houston Audubon site, calling for a “lights out” period from May 9th to 12th. Heavy migrations were predicted the week before the Sioux Falls fallout…but FAR to our south and east.

The result of the changing weather pattern…an absolutely spectacular weekend of birding in the Sioux Falls area the weekend of May 17-19, particularly as the forecast deluge mostly fizzled out. I admit that even I as a scientist was somewhat skeptical of the Cornell BirdCasts. But after the events of that weekend, count me as a firm believer!

Here are some photos of the spectacular birds of that weekend:

Scarlet Tanager - Piranga olivacea
Scarlet Tanager – May 18th, 2019 Good Earth State Park, South Dakota
Magnolia Warbler - Setophaga magnolia
Magnolia Warbler – May 18th, 2019 – Good Earth State Park, South Dakota
Henslow's Sparrow - Ammodramus henslowii
Henslow’s Sparrow – May 19th, 2019 – Newton Hills State Park, South Dakota. Great weekend of birding overall, AND a lifer? I’ll take it.
Great Crested Flycatcher - Myiarchus crinitus
Great Crested Flycatcher – May 18th, 2019 – Good Earth State Park, South Dakota. Flycatchers in general seemed almost non-existent, prior to this weekend.
Mourning Warbler May 18th, 2019 Good Earth State Park, South Dakota. Not a great photo, but Mourning Warblers are a species I see occasionally, some springs. On May 18th, I ran into probably a dozen at Good Earth State Park.

Meteors in your Gutter, Pollinating Crops with Drones, and more science news – Week of March 12, 2017

This week, let’s try something novel…science news, sans politics.  It seems that politicians in this country have decided we can live without science, so for one week, I’ll try a “news” post where science avoids politics.

Long-horned Bee - Melissodes

A Long-horned Bee, doing what bees do best…collecting nectar and in the process, distributing pollen. If one Japanese researcher has his way, we could soon be using drones to augment nature’s pollinators. A personal comment…let’s hope this never comes to pass.

Who Needs Honeybees when we have Drones? — A first…TWO drone-related stories in one week! While the story above about using drones to acoustically sample birds may seem practical, I admit I don’t see much of a future for this application!  Eijiro Miyako, a chemist in Tsukuba, Japan, was trying to make an electricity-conducting gel in 2007, an endeavor that wasn’t working. His concoction was stored, until 8 years later when he dropped the jar while cleaning out a drawer. Miyako certainly thinks differently than I do, because upon cleaning up the sticky substance, he wondered, “could this be used to pollinate plants”? The decline of honeybees and other pollinators is well-noted, something of potentially devastating consequences to not only natural ecosystems, but to our very survival, given the need to pollinate crops.  Miyako started working with methodologies to pollinate crops, starting out by coating ants with his sticky gel to see if their movements would attract and distribute pollen. It kind of worked, but didn’t seem practical, so he eventually started working with drones.  The drones have a fuzzy material that collects pollen and can redistribute it when the drone brushes up against another plant.  His eventually plan? Build a fleet of 100 or so drones, use GPS and artificial intelligence, and set them loose in a field to pollinate the crops. Well…I guess we all need dreamers, and given how science works, who knows what practical application may come of Miyako’s work?  But hey, how about instead of developing drone pollinators, we instead focus on preserving the natural pollinators we have now?

Norwegian Gutters Clogged with Meteors!! — Jon Larsen, a Norwegian jazz musician, has an interesting hobby.  He’s devoted much of his free time in recent years to looking through material in gutters, downspouts, and drains, searching for extraterrestrial visitors.  Tons of material from outer space enters Earth’s atmosphere every day, much of it microscopic. Larsen has searched through debris in urban settings in search of these microscopic visitors.  His passion has been published in the journal Geology, with a paper that discusses the identification of over 500 “large micrometeorites” from rooftops and other urban settings. Larsen has learned the typical characteristics of micrometeorites, stating “Once I knew what to look for, I found them everywhere”.  Next time you’re up on the roof, cleaning leaves out of those gutters, do it with a smile and a sense of wonder, because it’s extremely likely that you’re cleaning up cosmic debris along with those leaves.

Normalized Difference Vegetation Index - Great Britain

Normalized Difference Vegetation Index (NDVI) for Great Britain, showing relative “greenness” of vegetation at the time. Researchers are studying linkages between NDVI, tree ring width, and volcanic activity to see if vegetation is responding to pre-eruption conditions. Potentially, such changes could be used to help predict an eruption.

Predicting Volcano Eruptions from…the greenness of trees? — I believe this is a poorly written article, but the premise behind it is VERY cool for a scientist like myself who works with satellite imagery.  The title of the story is very poor and somewhat misleading, stating “Can tree rings predict volcanic eruptions”? The story focuses on the work of scientists at the Swiss Federal Institute for Forest, Snow, and Landscape Research. In 1973, scientists noted an anomaly on satellite images along Mount Etna’s flank, a streak of trees that were greener than normal.  With satellite imagery, we can measure a “Normalized Vegetation Difference Index”, a measure of live green vegetation.  NDVI measurements in 1973 satellite observations were high along a streak on the volcanos flank, and less than a year later, a flank eruption occurred right along that very streak.  These scientists hypothesized that measuring tree rings from 1973 would also show an anomaly, and thus the title of this story that tree rings could “predict volcanic eruptions”.  However, the actual results showed no difference in tree ring width during that time frame. Given the relationship between tree ring width and how “good” a year a tree has had, I can see why continued research is warranted to try to find relationships between increased NDVI greenness, and tree ring width, and see if other areas have experienced changes prior to a volcanic eruption.  As it is, there’s not much in this initial research that proves a strong linkage.

Spying on Birds with Drones — On-site surveys of birds is a time-intensive and potentially expensive endeavor if trying to systematically survey birds across broad regions. Researchers at Gettysburg College in Pennsylvania investigated the use of drones for conducting acoustical surveys of birds. They tried flying a drone and extracting acoustical information from a recorder on the drone, and found that the method was able to sample bird presence for about as large a region as a human observer performing a survey.  They have some kinks to work out, primarily related to the noise of the drone masking some of the low-frequency bird noises (think cooing of a Mourning Dove), but they believe technological innovation will soon make drones quieter and more efficient at sampling bird acoustics. I admit I do kind of roll my eyes when I hear people talking about trying to use drones for photography, and for science applications, because in many cases it seems like a stunt more than an actual practical application.  Gettysburg College may be proving me wrong, as this actually does sound like an interesting use of drone technology.

American Chestnut - Wild Survivor

One of the VERY few wild, mature American Chestnut trees left in the wild. Trees such as this may be resistant to blight, and are being used in efforts to develop a blight-resistant stock for eventual transplantation in the wild. Genetic modification is also being done to introduce Chestnut Blight resistant genes in tree stocks.

American Chestnut, Returning to a Forest Near You? — I often wonder what it would be like to travel back in time, to visit locations before they were touched by man. In the United States, the entire eastern half of the country was once dominated by forest land. While forest cutting started in earnest in the 1800s and even earlier in some locations, remaining deciduous forests by 1900 were still populated by 3 to 4 billion American Chestnut trees. It is estimated that one-quarter of trees in the Appalachians were American Chestnuts.  The American Chestnut was a prolific nut producer, with mast from the trees supporting deer, turkeys, bears, and other wildlife, including the now extinct Passenger Pigeon.  In 1904 a fungal blight was discovered, a disease that eventually wiped out nearly every wild American Chestnut. Asiatic Chestnut trees were imported into the country, but with them came an Asian bark fungus that was lethal to American Chestnuts. The disease spread rapidly, killing every American Chestnut tree in its path.  It is now estimated that fewer than 100 trees of any size are left in their former range. Root systems of surviving trees still send up shoots, but the blight infects the trees as they mature, resulting in practically no American Chestnut stems over 10-years old in the wild.  This story is focused on efforts to genetically modify the American Chestnut to include resistance to the blight. 30 years of research has resulted in the introduction of a gene from wheat that makes the trees able to withstand the blight. They hope to gain approval to publicly distribute the trees within 5 years.However, it will still be a long process to repopulate Eastern forests with American Chestnut. The researchers want to cross-pollinate the blight resistant trees with native wild tree stock. Half of the offspring will be blight resistant, and genetic diversity will be much improved over the current research tree stock.  We’re at the start of a VERY long process to restore the tree to the wild, but hopefully our great-great grandchildren will be able to enjoy the same Eastern forest trees that existed prior to 1900.

10 years until “Snowball Earth” — I admit my scientist side geeks out when I read a story like this, as it’s just so cool to think of the physical changes that have, can, and will again happen to our Earth.  Of course the absolutely catastrophic consequences for mankind put a bit of a damper on that excitement!  Harvard scientists have pinpointed the circumstances that led to “Snowball Earth”, a period about 717 million years ago where the Earth was covered in ice from pole-to-pole.  Models suggest that the climate destabilization that plunged the Earth into polar hell could have happened in a blink of an eye in geologic time. Massive volcanic eruptions back then could have ejected enough aerosols into the atmosphere in just a 10-year period to initiate the rapid freeze.  Don’t worry, it’s not a single volcanic eruption that’s capable of such a long-term change, but instead the kind of massive eruptions that mankind hasn’t experienced in our history. 717 million years ago, it was a string of volcanic eruptions across what’s now Canada and Greenland that set off the freeze.  As I said, from a scientific standpoint, fascinating to think what could happen, but it also points out the fragile balance of our climate system.  “Snowball Earth” happened because of runaway cooling and feedbacks that amplified and accelerated the cooling, primarily with increased ice increasing reflectance of solar radiation in a self-reinforcing feedback loop.  Right now we’re playing a game of “chicken” with our climate system, doing the exact opposite, and removing that ice in a self-reinforcing feedback loop that’s amplifying warming.

Snowy Bison

The Bison, invasive species that forever changed North America! Well, if we were around about 150,000 years ago, they would have been considered an invasive species, one that transformed grassland ecosystems of North America.

Bison Contributing to Mammoth Decline?  — OK, my chosen title here doesn’t reflect the purpose of this research, but after reading the story it did make me curious…did Bison contribute to the decline and eventual extinction of the Mammoth? The story used DNA analysis to establish that the ancestors of North American Bison first arrived between 130,000 and 190,000 years ago.  As the story notes, in this case, Bison were the invasive species, rapidly colonizing North America and forever changing the grassland ecosystems of the continent.  It does make me wonder…if not for the establishment of the Bison as a primary grazer in North America, would the Mammoth and other North American megafauna have been better positioned to withstand climate change and the establishment of man? Interesting story, and a story that shows that not all “invasive species” are those that are introduced by mankind.

Managing Diabetes with your Sweat — Especially as a family that deals with the consequences of Juvenile Diabetes, we’re quite familiar with the frequent finger prick to check glucose levels in blood. Researchers in South Korea have developed a prototype glucose sensing and insulin delivery device that looks like an arm cuff.  Instead of measuring blood glucose, it measures glucose in sweat. It’s not just these guys, there are also other researchers who are looking at measuring glucose levels in tears. There certainly have been many technological advances and devices for testing and treating diabetics, innovations that are certainly welcome! I just wish there were some real advances on actually treating the disease, and not just the symptoms.
 

Predicting that next winter finch irruption

Pine Siskin - Spinus pinus

A Pine Siskin, a regular but unpredictable visitor in winter in South Dakota Research shows that southward irruptions of boreal finches such as Pine Siskins may be predicted from recent seasonal climate records.

Not a lot of time this week to blog, as I’ve been in pretty intense meetings all week for work.  However, it was through those meetings that I became aware of this interesting research paper.  Birders are always wondering when that next great “irruption” of boreal bird species will occur.  On occasion, boreal finches such as Common Redpolls, Pine Siskins, and Crossbills will move southward in great numbers from their boreal forest stronghold.  The thought is that such irruptions occur when poor “mast” production occurs, with lower conifer seed numbers than normal.  The birds thus move southward in search of food.

It’s not just boreal finches that are subject to occasional southward irruptions.  One of the greatest birding experiences of my life was during the huge boreal owl irruption into northern Minnesota over a decade ago, when Great Grey Owls and Northern Hawk Owls were seemingly “dripping off the trees”.  Those irruptions are thought to be due to a similar driving force…a loss of a primary food source…with periodic crashes of small rodent populations driving the owls southward in search of food for the winter.

The paper below (click to see it) gives an assessment of climate data to potentially predict when a finch irruption would occur.  The species studied here is the Pine Siskin, but the authors note that it may also apply for other boreal finch species that depend on conifer mast.  Cool study…

More coming next week!  Given I’m still in meetings the rest of the week and have family obligations all weekend, it’s likely the next blog post won’t come until Monday!  Click below for the study…

Predicting finch irruptions with climate information

Science MATTERS – A lesson from Joaquin

Graphic of potential paths for Hurricane Joaquin

September 30th, just a couple of days away from Hurricane Joaquin potentially impacting the U.S. coastline, and nearly all U.S.-based models had the hurricane directly striking the U.S. coast. The outlier? The (well-funded) European model that ended up correctly predicting the path far out to sea. A repeat of Hurricane Sandy, which U.S. models also struggled with, but the European model nailed.

It’s more than a bit depressing at times lately, being a U.S. government scientist.  Funding is a big part of that, as funding profiles for science in the U.S. government have definitely been on the downswing.  For my own project, I’ve had to cut quite a few very good people over the last few years, as the funding I receive to do land-use and land-cover modeling (future and past) has declined precipitously.  There are few things more maddening than working on a project, producing something the world has never seen, something that has tremendous value in helping science and society in general cope and plan for coming climate and land-use changes…and seeing your “reward” come in the form of massive budget cuts, forcing the release of great scientists (and friends).

While the budget declines have been disappointing, what’s even worse is the public attitude towards science in general.  Science and scientists used to be revered in this country.  They were representative of progress, of leadership, of the United States’ leading global role.  During the Cold War, scientific progress itself was as busy an arena for West vs. East competition as was geopolitical competition, with the space race captivating the world.

However, in the past decade or so, science has seemingly become the enemy for many.  As the conservative movement politicized what are inherently science issues, not political issues, the public’s opinion of science, and scientists themselves, has taken a hit.  Instead of admiration, there’s a broad sector of the public that now views scientists with skepticism and mistrust.  The politicization of climate change has certainly played a big role, as political talking heads push a pro-business, anti-environment message by attacking not only the science of climate change, but the integrity of the scientists themselves.  Suddenly scientists are being portrayed as liars and swindlers, pushing climate change research only to support some mysterious hidden liberal agenda (SO hidden that even as as a bleeding heart liberal I can’t see it), or to ensure the big research dollars keep flowing (I myself would LOVE to know where conservatives think all these “big liberal research dollars” are coming from….I could use them!!!).

In the meantime, science is suffering in the U.S.  Environmental protection?  Research for clean energy sources?  Spending on environmental monitoring and assessment?  All irrelevant, as they potentially impact short-term profit margins.   It’s not just “fringe” science that’s being impacted, it’s core research and scientific monitoring that’s crucial to keeping Americans safe.

If you followed Hurricane Joaquin last week, there was tremendous uncertainty in the path of the hurricane as it lingered in the Bahamas.  Scientists use “ensemble modeling” to better characterize uncertainty in difficult to predict events, with a wide variety of models used to assess the same phenomena.  Such an approach helps to form a “consensus” of multiple models.  For Hurricane Joaquin, ensemble modeling was used to help identify a variety of potential tracks.  In theory, the most likely path is something that the majority of models agree upon.

Last week, the models were all over the map.  Even by mid-week last week, the vast majority of U.S. based models were predicting Joaquin would track northward from the Bahamas, making a direct strike on the U.S. mainland, somewhere between the Carolinas and the New York area.  Mid week, there was one model, the primary European model, that was an outlier.  The European model predicted a Joaquin would jog to the northeast, missing the U.S. coast completely.  The European model, although the outlier in mid-week predictions, was the closest to the actual hurricane path.  U.S. models performed quite poorly in comparison.

For Hurricane Sandy, there was similar uncertainty.  For Sandy, the European model (correctly) predicted the hook into the New York area, while most U.S. models predicted Sandy would curve northeastward and miss the U.S. coastline.  Again…it was the European model that was correct, with U.S. models performing poorly.

There’s a great story on the New York times on how far behind NOAA and the U.S. Weather Service have fallen in terms of hurricane forecasting.  Raw computing power is an order of magnitude lower for U.S. models than for the systems being used in Europe.  Input data is lacking, as are other aspects of model parameterization.  In short, the U.S. simply has not invested as much in basic weather forecasting and research as has Europe.

As Sandy showed, and now as Joaquin has showed….the lack of adequate research funding for science in the United States has a VERY real impact on the everyday lives of Americans.  Clearly it’s not just weather research that’s an issue. Science funding profiles are declining for nearly all fields. Keeping Americans safe from weather events, natural disasters such as earthquakes and volcanoes, research on treating or curing disease, protection of our air, water, and food resources…all are suffering from lack of investment.

It’s a very curious disconnect right now, with technology-loving Americans seemingly often at war with science in general.  As Joaquin and Sandy showed, and as countless other examples have shown…there’s a real price to be paid for an inadequate investment in science.

Predicting that next invasion of winter finches

Common Redpoll - Acanthis flammea

A Common Redpoll, one of several “northern finch” species that sporadically invade the conterminous U.S. With this study, perhaps those irruptions could be predicted in the future.

It was 2 winters ago that we had an incredible redpoll invasion.  I’d never even had one in my yard before, and we’d lived in South Dakota for 20 years.  However, in the winter of 2013/2014, we had Common Redpolls around for several months.  A real thrill when one, and then another, Hoary Redpoll showed up at my feeders and stayed for a couple of weeks.

Such events are always a surprise, and it’s not just Redpolls.  Both Red and White-winged Crossbills are equally unpredictable winter invaders across the U.S., as are Pine Siskins and Evening Grosbeaks.  It was generally understood that large movements southward in the winter were due to poor seed crops for pines and spruces further north.  A new study from the University of Utah attempts to explain the winter invasions, based on climatic variables. First, the study finds that favorable climate patterns tend to shift across the continent. When one region is favorable to seed production, other parts of the continent are more likely to have unfavorable conditions for seed production, resulting in periodic movements in birds as they key in on areas with the most food resources.

The other climate finding is that it may be possible to predict irruptions to south up to two years in advance!  Seed production itself tends to be correlated with favorable conditions 2 or 3 years PRIOR to the actual growing season.  So, for example, if 2015 has unfavorable climate conditions in much of Canada, it may mean reduced seed production in 2017, resulting an increased likelihood of a southward irruption of northern finches. One of the things I love about birding is the total unpredictability, as you never know what you may see when you head out, but it would be cool to be able to anticipate a great winter finch season.

One final aspect of the work I like…they relied very heavily on eBird data.  A GREAT resource, but one that really isn’t being used for research nearly as much as other, more established monitoring programs like the Breeding Bird Survey.  If found the eBird data to be invaluable for the bird/climate/land-use study I published, and I think you’ll see more papers like this finch study use eBird data in the coming years.

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