(NOTE: This meeting and presentation took place online, via Zoom platform technology, due to social-distancing protocols prompted by the ongoing COVID-19 pandemic)
At 7:00 pm, President Ken Chaya called the meeting of the Society to order. He remarked on the challenging year we all faced in 2020 and the benefits of nature and community in helping us to get through such a difficult time.
He thanked the attendees for joining the meeting and expressed the hope that all will continue to attend LSNY programs in 2021. He said that as of the current moment, 203 people were watching the meeting live and thanked the LSNY Council, committees and past presidents for their continued help this year.
President Chaya reported that it is not yet known when the Society may return to presenting its programs in the Linder Theater at the American Museum of Natural History. Until then, we will continue to bring our programs online on a monthly basis.
Because the Society’s membership had recently voted online via email, there were only three business items on the agenda.
The first item was the news that Vicki Seabrook has been elected the newest member of the LSNY Council, with 113 unanimous votes of approval.
The second item was the result of a vote on the approval of new members. It passed with 112 votes of approval and none of disapproval. President Chaya then welcomed the following eight individuals as new members:
- Gale Page, Active Membership, Sponsored by Frank Smith
- John Maniscalco, Active Membership, Sponsored by Ardith Bondi
- Daniel Atha, Active Membership, Sponsored by Kevin Sisco
- Caroline Richard, Active Membership, Sponsored by Ken Chaya
- Erica Rosengart, Active Membership, Sponsored by Alice Deutsch
- David Schwartz, Active Membership, Sponsored by Miriam Rakowski
- Susan Schwartz, Active Membership, Sponsored by Miriam Rakowski
- Claire Borrelli, Active Membership, Sponsored by Amy Simmons
He then invited non-members in attendance to join the Society and explained that they could do so by visiting the LSNY website, www.linnaeannewyork.org. Additionally, he offered that he, personally, would be willing to sponsor anyone who would like to join, commenting that an organization is only as healthy as its growing and diverse membership.
The final item was the result of a vote to approve the minutes from the November meeting. It passed with 109 votes of approval and none of disapproval.
At 7:08 p.m., President Chaya introduced Donald Kroodsma, a birdsong scientist and professor emeritus of ornithology at the University of Massachusetts, Amherst. As a research scientist, Don has published widely on birdsong for more than 50 years, with lifetime achievement awards from the American
Ornithologists’ Union and the Wilson Ornithological Society. More recently he has authored books that introduce the general public to birdsong: the John Burroughs Medal-winning The Singing Life of Birds, The Backyard Birdsong Guides, Birdsong by the Seasons, and Listening to a Continent Sing: Birdsong by Bicycle from the Atlantic to the Pacific.
The title of Don’s most recent book (2020), Birdsong for the Curious Naturalist, was also the title of the evening’s talk. Both his book and his talk explore the beauty of the world of birdsong: songs and calls, female song, song learning and dialects, mimicry, matched counter-singing and counter-calling, night singing, complex songs, repertoires, and dawn singing.
Don opened by remarking that he finds something restorative about nature, and he invited the attendees to listen to birdsong a bit more deeply. He then introduced four key concepts that he would be addressing around the topic:
- Simple to complex
- Two-voice mimicry
- Female song
- Dialects and Dawns
1. Simple to complex
Starting with an example of a song on the simpler end of the spectrum, Don introduced the pitch-shifting of the singing Black-capped Chickadee. He shared visuals of its “hey sweetie” song as a waveform to show how loud it is, and then as a sonogram to show its frequency. Playing examples, he pointed out that if you listen during the daytime, a chickadee will sing “hey sweetie” all day at the same pitch. However, the pitch varied throughout his 20-minute recording of a single bird during the dawn chorus.
Moving to more complex songs, Don discussed his research in northern Michigan in April of 2017. He heard a birdsong that at first sounded to him like an exaggeration of the Black-capped Chickadee’s song. This bird turned out to be a Brown Thrasher. Noting that its songs resembled those of nine different species (Black-capped Chickadee, Eastern Wood-pewee, Common Loon, Eastern Meadowlark (call), Eastern Meadowlark (song), Chipping Sparrow, Northern Cardinal, Nashville Warbler, Northern Flicker, and Least Flycatcher), Don remarked that evidence for these songs being imitations rather than random sounds was bolstered by the fact that none of the songs were of western birds (which would have been out of range of this bird’s normal migratory flyway). In the course of three days, from April 26-28 of 2017, Don recorded this single thrasher singing a total of about 7,700 songs and 60 different “handles.” (One imitation every 130 songs; each of ten models occurs about six times; 7697/6 = about 1,300 different songs.) He noted that before females arrive, the males are singing intensely and matching one another. As an example, he told of two birds who did about 50 matches in only 8.5 minutes. One possibility is that the birds were making up sounds as they went along, matching each other, and another is that they already had these repertoires established and were simply drawing from them.
In an attempt to better understand how the Brown Thrasher vocalizations came to be, Don then researched a closely-related species, the California Thrasher. In March of 2017, at Montana de Oro State Park in California, he was “blown away” by an individual of the species that he heard there. Each day, the singing bird had a different, particular “theme,” which is almost the opposite of how the Brown Thrasher sings. In a sense, each day, the California Thrasher was withholding some of what it knew. Each day’s singing was very different from that of the other days, as could be heard in the samples he played for the audience.
Moving on to the Northern Mockingbird, he referenced its extensive mimicry, reporting how he once heard a single individual bird imitate 14 different species. That said, again in Los Osos, while listening in the middle of the night he heard two birds engaging in song matching—audio examples of which he shared with the audience. (Don also noted that unpaired, bachelor birds do often sing in the night.) The song matching was rather astounding to him, as the two birds didn’t use mimicry which is so typical of mockingbirds.
2. Two-voice Mimicry
After acknowledging the negative feelings some have about European Starlings, Don went on to say that their songs are very under-appreciated. He then played a continuous 49-second song from a single individual, in which the bird imitated a phoebe and a flicker simultaneously by using both its right and left voice boxes. He said that the two voice boxes present in the European Starling can be controlled independently, and said he found this to be a bit of a “miracle.”
3. Female Song
It is not only male birds that sing. In particular, Don cited the female Northern Cardinal as one known to be a frequent singer, particularly when it is incubating eggs on the nest. Playing examples, he said that the female sometimes does song-matching with the male when she is on the nest and he is nearby. In addition, Northern Cardinals often match one another from neighboring territories.
The female Rose-breasted Grosbeak also sings from the nest. To our ears, the song of the male Rose-breasted Grosbeak is extraordinarily beautiful. (Human ears are adapted for birdsong that is “slow and low.”) According to Don, if you sit near a nest, you’ll hear the male singing as he’s coming in (he sits on the nest, as well). Although it gives away his location, the male will also sing from the nest.
When singing a dawn song, the Rose-breasted Grosbeak will sing a long, continuous series of notes from the ground, whereas during daytime, he will sing from the treetops or the nest. Also, as shown by sonograms of a singing male grosbeak, most of the sound occurs between 2-3.5 kHz, but when he sings a courtship song to the female at dawn, he sings portions of his song at a very high 10kHz.
4. Dialects and Dawns
Don said that one of the questions birders most want answered is why some families of birds learn songs, yet others do not. Interestingly, Anna’s Hummingbird is a song-learning hummingbird, but it sings so fast that our ears don’t really hear the song. Anna’s hear (and learn) details that we can only hear at slowed-
down speeds. It seems that birds can hear in real time much better than humans can. If we slow the sound down, we can hear the details, perhaps in the same way that they can. Don also reported that by looking at sonograms of Anna’s Hummingbird songs from different areas in California, he was able to identify features of each that the songs of birds in the other locations lacked. In other words, the birds were singing the same songs, but in different “dialects.”
Chipping Sparrows also have mini-song dialects. He pointed out that one can quite often walk through a park or golf course, position oneself between two Chipping Sparrows, and hear them sing two seemingly identical songs. Noting this, he listened to recordings and looked at sonograms to see just how similar the songs of two neighbors were, and found that the songs were indeed essentially identical. This is because each male learns his song from a single adult male. So, when you hear males singing identical songs in the same area, you can presume that they have learned their songs from one another and have a relationship of some kind.
Don then played the “lek-like” dawn singing of three male Chipping Sparrows that he had recorded in the dark in Missouri—calling it one of the “most intriguing examples of what birds do during the dawn chorus.” As could be heard in the recording and seen on the sonogram, each bird had a unique sound, and the members of the “lek” sang them at one another for five minutes. Because each song was unique, after another thirty seconds, it could be heard that bird #3 had departed and bird #4 had now arrived. This example gives a bit of a window into what’s going on in the dawn chorus: males are congregating at territory boundaries and having “song battles”—with Chipping Sparrows providing an extreme example of what’s going on. Don went on to explain that at dawn, lekking interactions take place among males on territories to which the birds who own them return later in the day.
He concluded by encouraging attendees to “go out there and listen,” and made some suggestions for doing so:
- Listen to one singing bird. Compare successive songs and note how they change with the time of day and the seasons.
- Try to determine a “handle” (or unique song) that you will know when you hear it again for more complex singers.
- Listen to singing neighbors. How is each individual fitting into the community? Note and listen to the various species. Try to think in an evolutionary context how each song came to be.
8:05 p.m., Vice-President Rochelle Thomas thanked Don for his talk and facilitated the Q&A portion of the program.
8:22 p.m. Vice-President Thomas passed the floor back to President Chaya, who thanked Don, saying that by the end of the program, 273 viewers had tuned in. He then invited attendees to return for next month’s program, “The Songs of Trees: Stories from Nature’s Great Connectors,” presented by David Haskell, Ph.D.
8:24 pm – The meeting was adjourned.
Respectfully submitted by Amy Simmons, Recording Secretary