Conservationist Aldo Leopolds Soundscapes Recreated

CURWOOD: In the early morning before dawn, Aldo Leopold would sit on a bench outside his shack in Sauk County, Wisconsin, with a pot of coffee and a notebook. And as the sun rose, he took detailed notes as each bird joined the dawn chorus. Aldo Leopold was well known for his observations of the natural world, gathered in his 1949 book, A Sand County Almanac, that many consider to be some of the finest essays on the intrinsic value of nature.

Well, now we can actually hear the chorus that Aldo Leopold made note of in his morning journal, thanks to a team led by Stanley Temple, Professor Emeritus in Conservation at the University of Wisconsin-Madison. Professor Temple joins us from Madison. Welcome to Living on Earth.

TEMPLE: Glad to be here!

CURWOOD: So, Aldo Leopold is an iconic figure to some, but for those of us who aren’t as familiar with his work, who was Aldo Leopold?

TEMPLE: Aldo Leopold was probably the most influential conservation thinker of the 20th century. His career spans the first half of the 20th century and during that time he made some remarkable contributions. He began his career as a forester, but by mid-career he turned his attention to broader issues of conservation. And for most people, what they know best about Aldo Leopold, was that he left us, A Sand County Almanac. This was, essentially, the culmination of his life journey and it expressed his ideas about our relationship with the natural world.

CURWOOD: Professor Temple, you’re a scientist by training, so how did you become so interested in this historical figure?

TEMPLE: Well, I was fortunate during my 32 years as a faculty member at the University of Wisconsin to have occupied the chair that Aldo Leopold once held. Not only was he a hero of mine personally, but because of my professional ties to him, I made it my business to learn more about him, and the University’s archives has just a remarkable collection of his papers. And among those papers I discovered an unpublished manuscript that he was working on at the time of his death, in which he described the work that he had done over a decade of time studying the dawn chorus of birds, and in particular, how the sequence of songs plays out in the early morning light.

CURWOOD: What scientific observations did Aldo Leopold make about the morning bird chorus?

TEMPLE: He became fascinated with the sequence in which birds joined the dawn chorus and he was working on a hypothesis that the sequence was determined by light intensity; that each bird joined in the chorus, cued, you might say, by the intensity of the light. He bought one of the earliest light meters that were available, something that measured light intensity. He was very early in sort of posing this hypothesis. Others in the 1950s, when the technology was better, followed up and, indeed, verified that Leopold’s ideas were correct.

CURWOOD: Please describe for us Aldo Leopold’s dawn birding routine.

TEMPLE: Well, we could actually use his own words because he does describe it in nice detail in one of his essays in A Sand County Almanac called “Great Possessions”:

“My daily ceremony, contrary to what you might suppose, begins with the utmost decorum. At 3:30am, with such dignity as I can muster, I step from my cabin door bearing in either hand a pot of coffee and a notebook. I get out my watch, pour coffee, and lay notebook on knee. This is the cue for the proclamations to begin.”

CURWOOD: What gave you the idea to try and recreate the sounds that Aldo Leopold heard in his shack there in Wisconsin?

TEMPLE: Well, having read the unpublished manuscript, it struck me that you could put together, from his notes, all of the ingredients that would be required to recreate the sound that he was hearing. Well, it lay on the shelf or in the filing cabinet for many, many years and this past summer Brian Pijanowski, who’s one of the leaders in the new soundscape ecology movement, invited me to give the keynote address at an NSF workshop that was held at the Leopold Center here in Wisconsin. And I thought this was the perfect incentive to actually go back and see whether indeed we could recreate the soundscape Leopold was listening to from his notes.

CURWOOD: What was your process?

TEMPLE: Well, the process was first, of course, to go through all of Leopold’s notes and develop what you might say is a score. And then I enlisted the help of Chris Bocast, a graduate student here at the University of Wisconsin campus, who is an excellent audio engineer. And with the help of the Cornell Lab of Ornithology providing the actual recordings of the bird songs, we were able to put together a facsimile of what Aldo Leopold was listening to back on June 1st, 1940.

CURWOOD: I’m wondering what kinds of materials you were working with here; what did Aldo Leopold’s notes look like?

TEMPLE: His notes were taken in a shorthand and what he noted was the time at which he first heard each bird joining the chorus. And he then took notes on how frequently he heard each species singing. So with that information, we could actually put the birds into the proper sequence and the proper timing of their calls but it went further than that. If you listen to the tape that we produced, in stereo, we’ve actually placed the birds in the soundscape in the relative positions that they should be in based on Aldo Leopold’s territory maps. So the birds that appear to be coming from the left are birds of the field and prairie. The birds that are coming from the right are birds associated with the woodland and the birds in the middle are the ones associated with the edge in between the field and the woods.

CURWOOD: Were going to play a clip from your soundscape now. Please, identify some of the sounds for us as we listen.

[ROBIN SINGING]

TEMPLE: Starts off with the American robin, an early riser.

[BIRD CALLS UNDER THE DISCUSSION]

TEMPLE: You can hear some birds in the distant background but the next bird to join is a field sparrow.

[TRILL OF FIELD SPARROW]

CURWOOD: That trill is the field sparrow?

TEMPLE: That’s the field sparrow. We paid attention to the birds that were very close to Leopold, the ones that, as he said, he paid attention to. The next bird you’re going to hear is an indigo bunting.

[CALL OF INDIGO BUNTING AND DISTANT CROWS]

TEMPLE: You can hear crows in the background.

CURWOOD: Good thing they were in the distance. They can be pretty loud.

TEMPLE: Yeah!

CURWOOD: Now, is this a compression of time or is this in real time here?

TEMPLE: We did compress the time; we didn’t compress the bird songs. What we did we compressed the intervals between each bird’s calls, but we compressed them proportional to Leopold’s notes. So we actually compressed the first half hour of the day into five minutes. It still sounds pretty much like what it really does sound like. Just not quite so much down time between calls.

[MORE BIRD CALLS]

CURWOOD: Now who else has joined in here?

TEMPLE: The wood pewee comes in followed by the song sparrow and gray catbird. They start to pile on pretty quickly about this point.

[CALLS OF CATBIRD]

CURWOOD: OK, who’s that?

TEMPLE: That’s a catbird, sounding like a cat mewing.

CURWOOD: So what does the land around Aldo Leopold’s shack look like today?

TEMPLE: Well, it’s undergone quite a transformation since 1935 when Aldo Leopold purchased this worn-out farm that had almost no vegetation on it to speak of. He and his family spent many thousands of hours planting prairies, planting trees, and today, of course, what you see is a fairly mature ecosystem, and because of that the birds you hear today are a slightly different blend of birds, mix of birds, than Leopold was listening to. There are certainly more species in the dawn chorus today than there were in Leopold’s time because of the habitat that Leopold and his family created for them.

The Aldo Leopold Center (Photo: Rebecca Brown)

CURWOOD: So we’re going to play a clip now of the dawn sounds around the cabin taken from this summer. Let’s have a listen.

[BIRD SONGS AND TRAFFIC SOUNDS]

CURWOOD: Well, there are a lot more birds there but it’s pretty hard for me to hear them.

TEMPLE: That’s right. But what you do hear is the traffic from the interstate.

CURWOOD: How do you think Aldo Leopold would respond if he could hear the morning soundscape that you recorded in 2012?

TEMPLE: Well, I think Leopold already gives us a hint that he was, to some extent, offended by the sounds of humanity that were impinging on the natural sounds. I’m going to read just a couple of sentences from another of his essays from A Sand County Almanac called “Too Early,” in which he talks about arriving very early in a duck blind in a marsh.

“To arrive early in the marsh is an adventure in pure listening. The ear roams at will among the noises of the night without let or hindrance from hand or eye. Like many another treaty of restraint, the pre-dawn pact lasts only as long as darkness humbles the arrogant. By breakfast time comes the honks, horns, shouts, and whistles of an awakening farmyard and finally, at evening, the drone of an unattended radio.”

So Leopold was well aware that the sounds of human beings were intruding on the natural sounds. So I don’t think he would be surprised. I think he might have been certainly offended by the fact that the interstate highway came so close to his beloved shack.

CURWOOD: What’s your favorite passage from A Sand County Almanac that you would feel comfortable reading right now that captures Aldo Leopold’s thoughts on nature?

TEMPLE: Well, I think it’s one that many people who are conservationists are aware of. It’s one that gets quoted fairly often:

“If the land mechanism as a whole is good, then every part of it is good, whether we understand it or not. If the biota in the course of eons has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering.”

I think you could apply that golden rule of Aldo Leopold’s to the problems of soundscapes being polluted, if you will, by human-generated noises.

CURWOOD: Stanley Temple is a Professor Emeritus at the University of Wisconsin and a senior fellow at the Aldo Leopold Foundation. Thank you, sir.

TEMPLE: You’re very welcome.