Bar-headed Goose. Efficient breathing is important when migration
takes you over the Himalayas! CC BY-SA 2.0 Imran Shah
 

To accomplish their aeronautical feats, birds need to breathe efficiently. Last month, a team of physicists and applied mathematicians published a study of the structure of birds’ lungs. Unlike human lungs, in which air oscillates back and forth, birds’ lungs allow air to pass through in a one-directional loop. The researchers used piping to model this lung structure and water to simulate the flow of air. Through a series of experiments, they analyzed how the action of a bird’s breathing produces the efficient, one-way air flow that enables long-distance flight. 
 
According to the researchers, this knowledge of avian anatomy has potential engineering applications “from healthcare to chemical processing to the fuel, lubricant, and coolant systems in all sorts of machinery.” Coauthor Leif Ristroph, an experimental physicist and applied mathematician from NYU, summarizes this latest influence of birds on technology: “In all these cases, we need to pump fluids in specific directions for specific purposes, and now we’ve learned from birds an entirely new way to accomplish this that we hope can be used in our technologies.” 
 
In fact, bird-inspiration innovation is already widespread. Engineers have long looked to birds to inspire aerodynamic designs for planes and trains. The nose of Japan’s bullet train is perhaps one of the best known examples of biomimicry, or design that deliberately emulates nature. Early versions of the bullet train created a sonic boom when exiting tunnels, which disturbed people and wildlife in its vicinity. Engineers solved this problem by redesigning the train's nose in the shape of a kingfisher’s bill, thanks to the presence of a birder on the engineering team. This kingfisher-inspired design eliminated the sonic boom and decreased the train’s air resistance by 30 percent, which also improved its speed and energy efficiency. 

 

Bullet train, CC BY-NC 2.0 Todd Lappin
 

Unsurprisingly, birds have also served as the model for improvements in aircraft, and the very invention of the airplane owes much to birds; the Wright brothers observed birds to discern how the shape of the wing generates lift and how changes in wing shape allow birds to maneuver. Today, well over a century after the first flight at Kitty Hawk, birds continue to teach us new strategies for aeronautical engineering. As one recent example, a team of engineers and physicists published a study last year on the aerodynamic properties of owl feathers. Small structures on the leading edge of owls’ wings provide stability, reduce turbulence, and permit virtually silent flight. By learning from owl feathers, the researchers believe that wings can be designed to reduce noise from aircraft.
 

In 2016, the US Air Force awarded a $6 million grant to aerospace engineering researchers to conduct an in-depth study of bird flight. Meanwhile, other engineers are developing drones that perch like birds in order to save power or recharge. And Airbus is currently looking to geese and other migratory birds for guidance on how to fly commercial airplanes in formation, which the company believes will result in 5 to 10 percent fuel savings on long-haul flights. 
 
While it may be no surprise that birds have much to teach humans about the mechanics of flight, the special adaptations of other types of birds have inspired design innovations in other industries as well. For instance, woodpeckers routinely experience forces of 1200g to their heads, fifteen times the amount of shock needed to give a human a concussion, and more than the impact that a typical flight recorder is designed to withstand. In the past decade, engineers have begun adapting the structure of the woodpecker’s head to new shock absorbers to protect sensitive electronics.
 

Of course, nothing is more uniquely avian than the feather, and, at the University of Akron, polymer scientists have created non-toxic pigments inspired by bird feathers. Similar research has recently been conducted at Japan’s Nagoya Uni­versity, focusing specifically on the way in which the structure of feathers produces the blue color seen in birds like the Stellar’s jay (the main focus of the research team’s investigation). From Eastern bluebirds to indigo buntings, birds with blue feathers lack blue pigmentation; instead, air pockets in the feathers scatter light to produce the birds’ vibrant colors. Bird-inspired structural colors may permit manufacturers to reduce the need for dyes, which can be detrimental to the environment. 
 

Indigo bunting (no blue pigments!), CC BY-ND 2.0 Kelly Colgan Azar

These innovations represent only a few of the ways in which birds can teach us. As one more example, songbirds, parrots, and hummingbirds are among the most human-like animals in terms of their abilities to learn vocal sounds from parents and others in their communities. Even the other great apes lack the vocal learning abilities shared by humans and many birds. Thus, some scientists are now investigating birds to discover more about language-learning in humans.  

 
For most of us, bird conservation needs no further justification than the joy and happiness that birds bring to our lives. However, although birds are their own reward, they have much practical knowledge to teach us too!   

by Lauren Bradford, University of Delaware

New metric can help determine when birds fly over a site or stop to refuel or rest

 
Each spring, billions of land birds -- thrushes, warblers, orioles, tanagers, and more -- migrate through the night, navigating the coast of the Gulf of Mexico. Even greater numbers migrate in the fall. During the day, these birds stop to rest, recover and refuel for the next leg of their journey. These two phases of migration -- passage (flight) and stopover (rest) -- are well understood in ornithology but had previously only been studied independently.

Research in the journal Ecology Letters combines these components into a new metric called the stopover-to-passage ratio. This study is the result of a collaboration between researchers at the Smithsonian Migratory Bird Center, Cornell Lab of Ornithology, University of Maryland Center for Environmental Science, Colorado State University, Georgetown University, University of Massachusetts and University of Delaware.

"The stopover-to-passage ratio is an indicator of the number of migrants that stop to rest during migration and those that continue heading north or south, depending on the season. The ratio varies from site to site," said co-author Kyle Horton, assistant professor at Colorado State University and an alumnus of UD's College of Agriculture and Natural Resources. "It's highly useful, from a conservation standpoint, to know if the majority of birds fly over a site or predominantly stop at a site to refuel or rest. The answer to this question can have important implications for what action is ultimately done on-the-ground to help migratory birds."

"Characterization of stopover habitat use relative to passage represents a fundamental gap in our knowledge," said Emily Cohen, lead author and assistant professor at the University of Maryland Center for Environmental Science, Appalachian Laboratory. "This gap primarily exists because a methodology to collect broad-scale information about distributions of birds in terrestrial habitats during the day and in the airspace at night has only recently become possible with weather surveillance radar."

Archived since the mid-1990s but only freely available since 2004, weather radar data collected by NOAA, the National Oceanic and Atmospheric Administration, now enables researchers to map the nocturnal habits of migratory bird populations. It is a herculean effort to process and synthesize these vast data sets; scientists must distinguish bird movement from precipitation data on the radar based on density, speed and knowledge of the natural history of bird behavior. Calculating both the traffic patterns of the birds in flight and their activity in stopover sites, the research team created migration maps and calculated the stopover-to-passage ratio along the entire U.S. Gulf Coast.

"Our findings were not what we expected," said Jeff Buler, University of Delaware associate professor of wildlife ecology and senior author on the paper. "We understand the phenology of migration quite well, so we know the absolute number of birds moving through an area at the peak of migration. The density of birds on the ground also peaks around the same time. When looking at stopover-to-passage ratio, we thought that we would see more birds stopping during the peak of migration but we actually found the opposite."

Even though fewer birds migrate outside of the peak window, a larger percentage of that bird population stops at particular resting and foraging sites, indicating that those lands are of critical importance at that time.

"We saw a high stopover-to-passage ratio in the panhandle of Florida, which was unexpected because in the spring there aren't as many birds moving through that area," said Buler. "What that tells us is that the birds that are moving through that area need to stop, and it actually is indirect evidence that these are likely migrants that are coming from South America. They're flying over the Caribbean and the Atlantic Ocean, so they're making a farther journey than those that are just crossing the Gulf of Mexico. That first place to land in Florida is really important to them and most of them have to stop because they've run out of gas. From a conservation perspective, this really opens up a question of whether we need to rethink how we prioritize conserving stopover areas."

Currently, breeding ground habitat receives far more conservation attention and protection than migratory stopover habitat. However, with migratory bird populations facing rapid declines due to many interacting factors including light pollution, climate change, and habitat loss and degradation, researchers hope that the stopover-to-passage ratio can offer additional insight and renewed interest in often overlooked stopover sites.

"These results show the critical importance of the habitats around the U.S. coast of the Gulf of Mexico and Florida for sustaining North America's migratory birds. We show for the first time that over half of the birds migrating through these coastlines stop there," said Cohen. "Further, disparities in disproportionate selection and absolute abundance at stopover sites revealed potential migratory bottlenecks where geography or restricted habitat may disproportionately concentrate birds along migration routes, highlighting that density of use alone is not a comprehensive measure of the conservation value of a stopover site for migrating birds, a topic that has not been addressed during migration. The areas where the stopover-to-passage ratio is high are potentially more important for migrating birds than was previously thought."

"Linking aerial and terrestrial habitats with this new metric provides a unique opportunity to understand how migrating birds, in this case very large numbers of them, use a region where we know drastic and rapid changes are occurring," said co-author Andrew Farnsworth of the Cornell Lab of Ornithology. "Whether for prioritization of critical areas or for developing dynamic conservation planning, this kind of quantitative science is invaluable for supporting decision-making that can safeguard this incredible region and the spectacular movements of birds that occur here annually."
 

 

Read about the spring migration and conservation experiences of three Ohio Young Birders Club members in their own words. They are our future!
 
Spring 2021 Birding
8th Grader: Matthew Rice
 

 
Spring began for me this year on March 10 with the Eastern Towhee at Blendon Woods. Blendon Woods has always felt like home for me, since I started birding in 2013 at the age of 7.  I regularly visit this park all year long because it’s a favorite. This year my favorite season (Migration Season!) started with that Towhee on the pet trail. Other signs of spring included the Louisiana Waterthrush, Golden-crowned Kinglets, and Yellow-throated Warblers.  The Yellow-throated Warbler by the duck blinds was cool because I was able to spend a lot of time with it and take some photographs.  The Sugarbush trail was a great spot last year, with a lifer Golden-winged Warbler!  Tip: boots for mud are important here, but it’s worth the trek. Look for the Barred Owl in the pines!

Last year I discovered birding at Blacklick Woods Metro Park, and have made weekly visits to the park this year.  The trails and boardwalks there are great and there are always friendly birders there.  Notable species this year include Swainson’s Thrushes, Wood Thrushes, Blue-winged Warbler, Yellow Warbler, Common Yellowthroat, Hooded Warbler, Blackburnian Warbler, Ruby-throated Hummingbird, White-eyed, Purple Finches, Baltimore Orioles, Red-eyed, Blue-headed, Warbling, and Yellow-throated Vireos, Rose-breasted Grosbeaks, Pine Warbler, Nashville Warbler, Ovenbird, Scarlet Tanager, and Northern Parula. I’ve been working on my bird calls a lot this winter and it’s been such a great tool to have. I feel like this year I solidly know my Black-throated Green and Pine Warbler calls because of Blacklick!

Since I’m in 8th grade and not driving, I will often rely on my more local patches.  Kiwanis Riverway is a good quick stop for me.  At Kiwanis Riverway, I found my first of year Northern Waterthrush and Palm Warbler. Soon after, I started to constantly hear high-pitched buzzy and nasal “tzeeeees!”–those feisty Blue-gray Gnatcatchers! It’s been a goal of mine this spring to get good photos of the Blue-gray Gnatcatcher, which is pretty challenging given that they are so fast!  I shoot with a Nikon P950 and love taking photos of birds and wildlife.  I also share a daily bird photo on my Instagram account @buckeyebirder.  Photography is really fun and I’d like to start getting into editing my photos when migration slows down.

My other close birding spot is Duranceau Park.  Only a few minutes away from my house and it’s a great place for migrants and a variety of birds!  Be prepared to pick through lots of Yellow-rumped and Pine warblers!  eBird has been a fun experience for me, and I’ve enjoyed logging my sightings.  The last day of April was great for me at Duranceau with 65 species in 4 hours.  That was one cool day for me!!  Birding “wave 2” has been excellent at Duranceau.  Notable species I’ve seen in the last two weeks include my first-of-year Magnolia, Cape-May, Black-throated Blue, Tennessee, Redstart, (American of course), Nashville, Prothonotary, and Chestnut-sided Warblers, and Veery.  Other notable birds this last week were a Black-crowned Night-Heron and a solo male Ruddy Duck.  That was a fun surprise!  A great park to explore.

I also frequently walk to city parks near me, which sometimes can be surprisingly good. Sunny 95 Park, Thompson Park and Reed Road Park are all spots where I’ve had good luck.  It’s fun to spot a warbler when you least expect it!  I find that the swamp in Thompson Park and the watersheds at Reed Road Park are the best.  Chestnut-sided, Black and White, Magnolia, Blackburnian, Blackpoll, Nashville, Yellow, and American Redstarts all visit these spots.

This spring there are two birds I am REALLY hoping to see this year.  The two lifers I’m in search of are the Worm-eating Warbler and the Kentucky Warbler.  I’m keeping my eyes and ears peeled! Keep on birding!

Matthew Rice is a proud member of the Central Chapter of the Ohio Young Birders Club and an 8th grader at Hastings Middle School.  His spark bird is the Indigo Bunting and his nemesis bird is the Kentucky Warbler. Matthew’s true passion is birding, but he also enjoys Astronomy, playing video games, hanging with his friends, family, and his two kittens George and Alfred.
 
 
Monitoring Nest Boxes
By Hannah Thomas, Ohio Young Birders Club
 
I am going into my third year monitoring the Bluebird Box Trail at Deer Creek State Park. There are 24 Bluebird Boxes that make up the original trail. They are used by Bluebirds, Tree Swallows, and House Wrens. The carports were added since they are used as nest sites by House Finches and Barn Swallows, with 9 nest sites. A Killdeer nest on the ground was added later onto the trail for monitoring when a pair took up nesting in a rock pile near some of the Bluebird Boxes. This year we have added two Kestrel boxes to the trail. The boxes were added early this year and so far have had European Starlings, whose eggs were thrown out, and more recently, Tree Swallows. The box appears to have two, maybe three, nests made in the corners. As of now, only one of the nests has eggs in it. The three small white eggs are how we identified the nest as a Tree Swallow nest.

With the addition of the Kestrel Boxes, we now have two types of invasive birds to watch for, House Sparrows and European Starlings. The House Sparrows have recently taken up residence in one of the Bluebird Boxes around the front pond. We have been using a trap to attempt to catch the birds and recently caught the male. We are expecting to have more trouble as we have seen more Sparrows around the area. Unlike the Bluebird Boxes, we do not have a trap for the Kestrel Boxes. All we can do is continuously throw out the eggs and hope that the European Starlings will give up nesting in the location. The boxes were a bit late for Kestrels to use this year, so we figured it was unlikely we would have a nest this year. However, we have high hopes that next year there will be an American Kestrel in at least one of the boxes.

Tree Swallow nests in Kestrel box

 
Me with one of the Kestrel boxes when we put them up.
  
.First nest of Bluebird babies this year.

  
The Biggest Week in Birding
By Adrianna Losey
 
The Biggest Week in American Birding went virtual for 2021. While many people were sad that the Biggest Week was cancelled due to the COVID-19 pandemic for the second year, The Black Swamp Bird Observatory and their volunteers made sure that birders could still participate. Part of the virtual biggest week included daily presentations from a diverse panel of people. I am grateful to say that I was able to present at the Biggest Week. I spoke about my time as a young birder and how birding has helped me grow. I was honored to speak, even though it was through a computer at home. Birders had the opportunity to register for speeches throughout the week. I registered for quite a few and have enjoyed every one of them. I applaud and thank everyone who has worked hard to put on the festival this year, even if it was a little different.  The Biggest Week is planned for in person next year, and I hope to see many birders there and enjoy our usual events.