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Cecily Hansen 

Welcome back to the Naturally Speaking Podcast. My name is Cecily Hanson, and this is part 2 of my conversation with Scott Weidensaul, a renowned author and naturalist who has spent much of his life studying migratory birds. When we left off last time, we were chatting with Scott about his work and how new tracking technology has enabled us to learn more about migration than ever before. We also talked about a few adaptations migratory birds have to enable their journeys. Now we will hear about how migratory birds know where to go when they're traveling long distances, how climate change impacts migration, and we'll learn about how we can best protect migratory birds.  

How do birds know where to go when they start their migration, and how do they know when it's time to start migrating? 

Scott Weidensaul 

So those are two really good questions. And I have to say that the answers to that are not entirely settled. The standard explanation is that for most birds, well we know that migration is not a learned process, that there is a genetically coded migratory instinct that tells these birds to fly in a certain direction at a certain time of the year for a certain length of time. The degree to which that may also entail some, well, certainly entails learned behavior, that birds will learn particular routes and follow them in future years. But, you know, birds are not being led south by mommy and daddy. With the exception of a few groups of birds like waterfowl, so like ducks and geese and swans, cranes, where you do have sort of mixed generation flocks, where young birds may be traveling with older generations, not necessarily their family, but at least older generations. There is actually, in those cases, kind of a cultural transmission of learning that, you know, the birds don't have to learn how to migrate, but they do learn specific routes, specific stopover sites. specific wintering areas.  

That's why people can raise whooping cranes in captivity and teach them to fly south following a giant black and white painted ultra-light plane that looks like, you know, that looks like an adult whooping crane and can teach them a route and basically reestablish a lost migratory route from, say, Nesita, Wisconsin to northern, the panhandle of northern Florida, which is what people have done to reestablish this eastern migratory population of whooping cranes. And once those cranes make that flight once, they can do it again and again and again and again, year after year on their own and teach their chicks to take that flight. So, but most other birds, you know, they just, it's genetically coded.  

You know, those Bar-tailed Godwits flying across the Pacific Ocean, the adult godwits leave first. In fact, they leave before the chicks are even fully able to fly. So a young Bar-tailed Godwit chick making its first migration across the Pacific Ocean is doing so either on its own or more likely in a flock of other, you know, inexperienced teenage Bar-tailed Godwits. And I've said this before, I would love to know what goes on in the brain of a Bar-tailed Godwit when it's in like day eight of flying across the Pacific Ocean and it has seen nothing but ocean day after day after day after day, where if it stops flying for even a few minutes, it's going to crash into the ocean and die. I mean, is there doubt? Is there fear? Or is there just this, you know, bone-deep certainty that they're doing what they need to do and heading in the direction they need to go? I mean, they cannot possibly know at a conscious level that there's a place called New Zealand waiting for them at the other end of this migration. It's just one of the profound mysteries of migration to me is, you know, what does the bird know?  

I have to say, one of the two scientists that discovered the fact that Bar-tailed Godwits lose their guts before they migrate, a fellow named Tunis Piersman from the Netherlands, renowned shorebird biologist. He thinks there's a lot more conscious thought going into migration, especially these extraordinary long-distance migrations than science has ever said. And I will say that we have consistently underestimated the intelligence of birds for about as long as we've been studying birds. My good friend Jennifer Ackerman, who's written a number of books like The Genius of Birds on that subject, has made that very, very clear. The science is showing that birds are vastly more intelligent than we ever gave them credit for before. 

Cecily Hansen 

Yeah, that is fascinating to think about. You mentioned earlier that birds navigate using the magnetic field of the earth and quantum entanglement. Could you talk about that a little bit more? 

Scott Weidensaul 

Well, I'm happy to with the provision that people understand that I am not a quantum physicist. And this is, you know, once you get into quantum mechanics, things just get weird. And this is weird. So, and credit where credit is due, the person who came up with this idea first was the late Dr. Klaus Schulten, who at the time was living in Germany and later moved to the United States and taught for many, many years at University of Illinois Urbana-Champaign. But back in the 1970s, Dr. Schulten was puzzled, he was curious about this notion of magnetic reception in animals in general, because there's a magnetic sense in bumblebees, in red-spotted newts, in bacteria. There's some slight evidence that there's a magnetic sense in people. And he recognized that there was something about this magnetic sense that was connected to vision, or at least to light, because if these magnetically sensitive organisms, including birds, are exposed to wavelengths of red or yellow light, they lose the ability to orient magnetically. So he proposed the idea that there must be a substance in the eye of birds that is magnetically sensitive, that is also sensitive to particular wavelengths of light.  

And so he postulated that it could be what's known as something called radical pair theory. And I am going to attempt an explanation here, which I once gave at an audience where I found out to my shock and horror afterwards, included a quantum physicist who said, Yeah, you got it basically right. So here goes. In the eye of migratory birds, we now know, and there's been a lot of research done in the last 15 to 20 years on this, that there's a compound called cryptochrome in the eyes of migratory birds. And cryptochrome is a protein pigment, excuse me, pigment protein. And it is also magnetically sensitive. And so what appears to be happening is as this bird is flying through the night sky, a photon of blue light from a distant star, and of course this is happening trillions of times a second in the eye of the bird. This protein, this photon of blue light, hits a molecule in the cryptochrome protein, knocks an electron off that molecule and into an adjacent molecule. So those two molecules are now essentially one thing in quantum terms. They are quantumly entangled. And under quantum theory, we are told by quantum physicists who are supposedly smarter than us, if you were to somehow move those two molecules anywhere in the universe, what affected one would instantaneously affect the other. They are essentially one thing. And that aspect of quantum entanglement is what supposedly is eventually gonna give us unhackable quantum computers and faster than light communication, but what it also does, sort of as a side note or a little like cherry on the top of the sundae, is it briefly magnetizes that pigment protein.  

And so the bird has a magnetically sensitive pigment in its eye. So as it is flying north through the waves of electromagnetic radiation that the Earth's core is sending out into space, It can somehow see it. We don't know what it looks like. It might be nothing more than a smudge in the eye of the bird, but it tells the bird if it is going, because it can see the angle at which these belts of radiation are emerging from the Earth's surface. It can tell whether it is going from the equator toward the pole or from the pole toward the equator in either hemisphere, doesn't matter which one. There's a couple of advantages of that for the bird. You know, about every 100,000 years, the Earth's magnetic polarity flips and the North Pole becomes the South Pole and the South Pole becomes the North Pole. And we're kind of overdue for that to happen any day now. When that happens, it won't matter to the bird because it's not the polarity. I mean, our compasses won't work, but the birds will be fine. And they've gone through this countless times over the last several million years.  

So that gives it, the bird its north-south orientation, but there's also, it also needs an east-west orientation magnetically, because if the bird's getting pushed off course by, for example, crosswinds, it needs to be able to course correct and move back to the, to its original heading. And birds have a way of doing that magnetically, but we're still not sure where that is. It seems at least possible that that sense lies in what's called the trigeminal nerve that runs through the upper mandible of the bird's beak. Because birds that have been, have had their trigeminal nerve experimentally severed seem to lose that ability to compensate for east-west displacement. But there's still some debate about that. And there may also be other ways in which birds are able to sense the Earth's magnetic field. It may not just be quantum entanglement and radical pair theory. There's some indication that some birds may be able to sense it through their ears. I mean, again, birds may be weirder and more complex than we've ever given them credit for. 

Cecily Hansen 

So, I'd like to talk a little bit now about how climate change has been affecting bird migration, specifically some species that call St. Lawrence County home in the summer. We have a lot of warblers here. How has climate change been changing their migration or affected it? 

Scott Weidensaul 

Well, I think anybody who's been paying attention recognizes that the seasons have been changing. And particularly in much of North America, spring is coming faster and earlier, year after year after year. Now, I realized it was still snowing when I was  at St. Lawrence University at the end of April, and the northeast is one place where it's gotten a little bit colder and snowier later in the season. But across much of North America, spring is coming earlier. And here's the problem. The birds are leaving their wintering grounds, because many of these birds, the warblers and vireos, thrushes and tanagers, orioles, are wintering in the tropics. And so they're leaving their wintering grounds on a schedule that is baked into their DNA. They really have no conscious choice about when they leave. They're programmed to leave at a certain time. And so these birds are at risk of falling farther and farther and farther behind the seasons.  

And one of the things that we can actually see with Doppler Radar and with eBird data combined is the way that with many of these species, when they've after they've migrated north, especially the ones that have crossed the Gulf of Mexico, like they hit North America and it's almost like they looked at their watches and went, holy crap, I'm late. And they rapidly accelerate their migration north. And so they're getting back as quickly as they can, but in many cases, it's weeks later than they did, you know, well, let me rephrase that. They're showing up more or less on the same schedule they did 20 or 30 years ago, but the seasons have advanced so that they're weeks and weeks earlier, so that these birds are essentially weeks and weeks late. And so they have to have time to recover their energy because nesting is energetically hugely expensive, especially for the female birds, laying all those eggs. But they have to, you know, find a territory, you know, attract a mate. you know, build a nest, lay their eggs, hatch those chicks. They ideally, they, you know, almost all of our migratory songbirds feed their babies insects, and particularly soft bodied insects like caterpillars. So ideally, they want a time period of maximum, of maximum hunger on the part of their chicks, where their chicks have the highest dietary and energetic demands to coincide with the peak abundance of small moth and butterfly caterpillars in the forests of northern New York State.  

The problem is that there's a risk that they could fall behind that, and that's called a phenological mismatch. Phenology is the study of the timing of nature. We haven't really seen this happen in North America yet, but in other parts of the world, like in Europe, there's a species called the Pied Flycatcher that winters in tropical Africa and flies back to the forests of Central and Western Europe. And starting in the 1980s through about the early 2000s, the period of the most critical period from like late April through the middle of May when these birds are sort of their chicks are at their most demanding, the climate started warming very, very rapidly. And these birds fell out of sync with the seasons to the extent that in many parts of their range, their populations crashed because they simply couldn't successfully raise their chicks. Their chicks weren't getting enough to eat. Now, there is a happy ending for the pied flycatcher. And this, I think, speaks to the adaptability of birds, which is something else that I think we tend to underestimate. For reasons we don't really understand, that period of unusual warming that was happening during that critical nesting period paused. Now the scientists that have been studying this for years are at pains to point out this does not mean climate change stopped. It just means that this really unusual accelerated period of early spring warming slowed and paused. But it was enough to let the pied flycatchers catch up. They rapidly evolved an earlier arrival time to the forests of Western Europe, and their population has largely recovered.  

So, you know, one of the points I keep driving home to people is we just need to give birds half a chance. But look, the fact is that climate change is affecting every moment of every day of every bird's annual cycle, everywhere in the world. I doubt there is a species of bird on Earth whose migration and breeding season and wintering season hasn't been altered at some level by climate change. Now, there are some species of birds, whose migratory patterns have shifted and remained in closer sync with the season. And these are birds like American Robins and Eastern Phoebes and, you know, Fox Sparrows and Brown Thrashers. So these are birds that for the most part, winter in the southern United States, maybe down into northern Mexico, where they have a pretty good sense you know, from season to season, whether it's an unusually cold late spring, in which case maybe they're not going to move north quite as early as they would otherwise, or an unusually cold late winter or excuse me, an unusually warm early spring where they might decide to head north a little bit earlier. So but, you know, if you're a Black-throated Green Warbler in the forests of Guatemala, you have no idea whether on April 28th, it's still snowing in St. Lawrence County. You know, you're just, you're going to move based on when your genes tell you it's time to move and it may get you there a little bit too late. 

Cecily Hansen 

So your newest book, ‘Return of the Oyster Catcher,’ talks about, I know, some recent conservation successes. Why do you think it's so important to tell more like uplifting and positive conservation stories in part with some more kind of sad stories? 

Scott Weidensaul 

Well, because I think people need hope. I mean, one of the worst things we can do as conservationists is just give up. And, you know, the news can seem so grim. And I want to be really clear. I'm not suggesting things are great for birds. I've been doing bird conservation for too long. I know that that's not the case. But I also know that we have made remarkable progress in the past for birds. And I look at my own history for that. I'm 67 years old. I graduated high school in 1976, the bicentennial year. That year, there were maybe a thousand bald eagles left in the lower 48. If you had told me that 50 years later, when we were celebrating the 250th anniversary of the nation's founding, that there would be 400,000 bald eagles in the contiguous United States. I would have thought you were delusional. It would have, I mean, bald eagles were almost gone. Peregrine falcons were completely gone from the east. Ospreys were on the ropes. We brought those birds back. 

We brought back waterfowl from the market hunting period in the 19th century, and then the collapse of wetland habitat from the 1950s through the 1980s. But in the 1980s, you know, Congress passed landmark legislation like the North American Wetlands Conservation Act that poured, in the years since then, has poured billions of dollars into protecting and enhancing and restoring wetland habitat. And it's brought ducks back. It's brought wetland birds like herons and egrets and ibis back. We may have been a little too successful with geese. I mean, my God, there are literally millions of Canada geese out there. But here's the crazy thing, Cecily. Almost all of those Canada geese that we see at office parks and ponds and municipal reservoirs belong to a subspecies called the giant Canada goose, Branta canadensis maxima, which until the 1960s was thought to be extinct. Wow. Literally, literally every one of those 4 or 5 million Canada geese out there can trace its heritage back to a tiny little founder population that was husbanded along by a guy named Forrest B. Lee in Minnesota. Who I mean, like supposedly every one of those geese can trace its ancestry back to an egg or a gosling that this waterfowl biologist held in his hand when he started captive breeding these birds. Now, I would argue perhaps Forrest B. Lee was a little too successful. But you know, we've done amazing things for birds before.  

And so, ‘The Return of the Oystercatcher,’ I mean, there's a whole section in there about how we turned oystercatcher populations around after declining decade after decade after decade. A couple of simple tweaks to increase the productivity of oystercatcher nests on the Atlantic and Gulf Coasts by an average of half a chick per pair per year has brought those birds back to robust health. I mean, I talk about Sage Grouse conservation in the American West rewilding in parts of Europe and the UK. You know, how a friend of mine, a fellow named Steve Kress, who founded something called Project Puffin back in the 1970s to restore puffins to one tiny little island on the coast of Maine, wound up almost by accident, creating a toolbox of techniques that have been used with hundreds of species of endangered seabirds around the world using decoys and audio lures and what's known as social attraction to rebuild lost seabird colonies, predator exclusion. You know, there are roadmaps for wider recovery.  

These are examples of how we've saved birds in the past and suggestions of how we can save birds in the future. Because look, the only way it's going to be impossible to save birds is if we don't try. So, my argument is, let's try. You know, we've got our work cut out for us. But look, it was bad before. Raptor conservation at Hawk Mountain, where I got my start as a raptor conservationist, it got its start in 1932, excuse me, in 1934, because in the late 20s and early 30s, people were going to that mountaintop not to watch hawks, but to shoot them. And they were killing thousands and thousands of raptors up there every fall. And One guy, a fellow named Richard Poe, decided to do something about it, and he took photographs of the carnage, and then he took it to, took those pictures to conservation organizations that kind of were mealy-mouthed about actually doing anything. In fact, I'm sad to say the National Audubon Society, its forerunner, the National Association of Audubon Societies didn't do much. And then he took them to a formidable woman named Rosalie Edge, who had a small group called the Emergency Conservation Committee. And she said, oh, this mountaintop is up for sale for back taxes. And she bought it, 1,400 acres, and declared it the world's first sanctuary for birds of prey. That was the start of raptor conservation worldwide.  

So, what's that old saying from Margaret Mead? Never doubt that a small group of people can make a change. Never doubt that an individual and make a change. And now there are hundreds, if not thousands of hawk watches around the world. Raptors are protected legally in the United States and Canada. You know, it's sometimes from the worst of times come the best of times. 

Cecily Hansen 

What can the average person like myself do to help migrating birds, particularly like this fall when migration season starts back up again? 

Scott Weidensaul 

So, there's a couple of things. One of the best things you can do is turn your outside lights off, especially if you have really bright lights. You know, we know that light pollution at night is a huge problem, especially in the fall migration, when there's a lot of young birds migrating south. We know that like the big... urban megalopolis along the I-95 corridor just draws these birds in like moths to a flame and often with fatal results. And so there's an increasing push in large urban areas to turn off lights on skyscrapers and other buildings at night to give the birds back their night sky. Remember, these birds are traveling at night. We didn't really talk about this, but one of the other ways these birds are navigating is by orienting using the stars overhead. So, they need to be able to see the night sky in order to find their way. So, turning off your lights at night is a great way of doing it.  

One of the things that you can do year-round that's critically important is if you have a cat, please don't let your cat outside because I don't care whether your cat brings them back. Your cat is killing birds. The cats kill between two and four billion, with a B, birds in wild birds in the United States every year. And look, it's just safer for the cat if they're not outside. They're not going to get eaten by coyotes. They're not going to get hit on the road. They're not going to wind up contracting feline leukemia. So, win for the birds, win for the cats. Keep your cats inside.  

If you have windows where you routinely find dead birds that have flown into the windows, there are some really simple things that you can do. Birds can see in the ultraviolet range. And so, and I don't have any financial connection with this company. There's a company called Feather Friendly in Canada that makes just tape, clear plastic tape that has these tiny little UV reflective squares that are about a quarter of an inch by a quarter of an inch. And you can make a grid work pattern. Like, for example, we have a slider door on our back deck. It's the only window in our house that does not have screens on the outside. And every year we would lose at least a couple of birds to that door. Until we put these feather friendly dots on, we have not had a single bird fatality at that door since then. Yes, it's you're looking through a pattern. I have found that we just don't even notice it anymore. It's like again, it's like putting a screen on your window. You don't really notice the screen. So that's, you know, those are two really good things because here again, probably 1 to 2 billion birds a year die flying into windows.  

So, I mean, those are really simple things you can do if you've got a little bit more room and a little bit more energy. Gardening with native plants, especially planting fruit, native fruit producing shrubs like native viburnums, native dogwoods, those are going to produce you know, those really high-quality foods that these birds need in late fall. You don't want to plant plants like pyracantha that hold their berries all winter because the birds aren't eating them because the berries are pretty much useless. You want, you want to plant species where the birds are going to eat those berries and that fruit like 30 seconds after it becomes ripe because that's what's going to give them the energy that they need to fly, you know, to the far side of the world. 

Cecily Hansen 

Awesome. Thank you. So, I'm just curious, mostly for myself, what you've been thinking about the recent popularity boom for birdwatching, particularly with people who are my age, like college students, 20-year-olds. Do you have any advice for amateur birders like myself? 

Scott Weidensaul 

Oh, sure. Well, if you don't have Merlin on your phone, get Merlin on your phone because it's a free app from the Cornell Lab of Ornithology that will help you identify the songs of the birds around you. And I find it's a real door opener for a lot of people because especially for those of us like me, and I am not wired for sound. I really have struggled all my life. I don't have particularly good hearing. I don't retain birdsong in my head very well. Merlin's a game changer for a lot of people.  

The other thing to do is just, you know, find your tribe. Get out there. There are so many more birding groups that will help you get out in the field, see birds. The demographics of birding are changing so dramatically. There are, as you say, so many young people getting into birding. The pandemic helped with that. There's also, you know, there's, you know, during the George Floyd era during the pandemic in 2020, Black Birders Week started. So there's groups of birds that are birders that are trying to get black and brown birders out there. Just earlier this weekend I was at a local festival where Queer Birders of the Seacoast were leading bird walks and like 40 people show up at this at this farm this pharma cue festival to take people out who'd never gone birding before to see the birds that were out there. So you know, no matter how you identify yourself, you can probably find a birding group that will that will welcome you and and sort of bring you bring you into this world.  

And here's the thing. Once you see how many birds are out there, once you experience that diversity, you can't unsee it, you can't unknow it. It will it will suck you in because the birds are their own best ambassadors. You know, there is so much life out there, so much diversity. You know, you will be one of those people who recognizes that twice a year, the entire world, the entire Western Hemisphere is flowing through St. Lawrence County, you know, being drawn from as far away as the southern tip of South America, going to the high Canadian Arctic and back and forth, you know, these waves of birds. And if you, once you know they're out there, you're going to want to get out there and see them. 

Cecily Hansen 

Yeah, it's amazing how like into it I got just in like a month or so now. It's like every time I go outside, I'm like, oh, well, there's a grackle and there's a Veery and just like everything. It's amazing. 

Scott Weidensaul 

Everything, it just absolutely opens your eyes to it. There's no question about it. 

Cecily Hansen 

Yeah, well, thank you so much for being on the podcast. Thank you for your great answers as well. I really appreciate you taking the time to talk with me today. 

Scott Weidensaul 

All righty. Take care, Cecily. Good talking to you. 

Cecily Hansen 

Bye. 

Scott Weidensaul 

Bye-bye. 

Cecily Hansen 

Thank you for listening, and a huge thank you to Scott for teaching us all so much about migratory birds. I encourage all of you to spend some time outdoors and look up at the sky during migration season this fall, because you may see some new and wonderful things. Birds are all around us all the time, and they are incredibly beautiful and diverse. Birdwatching is one of my favorite ways to connect with the environment, and I hope it will become one of yours as well. As always, get up and get outdoors with Nature Up North. 

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