We’ve probably all heard someone say ‘You can’t see the forest for the trees!’ to let someone know they are too caught up in the weeds to see the bigger picture.
I’m happy to say that I’m seeing the forest through the trees AND the birds now after coordinating Maine Audubon’s Song Meter Project over the past several years. The big picture is clearer thanks to dozens of birders, volunteers, and our partners at four sustainable forestry demonstration sites who have helped Maine Audubon take a closer look at how forest breeding birds respond to woodland management conducted with ‘Birds in Mind.’
In 2019 and 2020, volunteers and partners contributed hundreds of hours—in fact over 1500 hours!—to help us identify birds at sites where steps are being taken to enhance critical habitat features for forest birds. We focused on locations with riparian areas, small gap openings within the forest interior, dead snags, large trees, multiple vegetation layers, thick leaf litter, downed logs, or lots of woody material on the forest floor–habitat features important to different species of forest birds and characteristic of mature forests. Participants visited these sites to look and listen for birds, placed audio recorders known as Song Meters to record what’s singing there, and later sat down to listen to the recordings to identify the types of birds that breed, forage, and stop over at these sites.
The data collected by these observers are contributing to Maine Audubon’s Forestry for Maine Birds (FFMB) Program and helping inform the recommendations we provide to loggers, foresters, and private woodland owners about how to manage their forests in ways that benefit birds and other wildlife. We expect to have the opportunity, in the coming years, to take another look at some of these FFMB forests to see which bird species are supported once habitat management practices have had some time to mature. Luckily this time it’ll be a bit easier.
Back in 2020, it proved too challenging to identify birds recorded by the song meters using computer software; we were only able to tease a species list from the recordings when dozens of volunteers strapped on headphones and spent hours listening. However, with the recent emergence of BirdNET Sound ID–Cornell’s online audio recording analysis tool–and the help of some intrepid volunteers, like Earl Johnson and James Longo, we’re now able to circle back and find out which birds are singing in hundreds and hundreds of hours of forest recordings in a tiny fraction of the time! And the effort is shedding additional light on our work in 2019 and 2020. (Look for some of the highlights of what we’ve learned in upcoming issues of Habitat and future blog posts).
So, just how much can we really ‘see’ and learn about the forest—its composition, structure, habitat features, and ability to support wildlife—through the birds that breed, nest, forage, and rest within it? According to those contributing to this project, the answer is, “Quite a lot!!” They also had a lot to say about how well song meter recordings measure up to birding in the field and how findings from technological tools compare to the human ear.
Take Jess Costa, an avian biologist at a local environmental consulting firm and a former seasonal biologist with Maine Audubon’s Piping Plover and Least Tern Recovery Project, who donated time to identifying birds in our recordings and conducting bird counts on-site at Sewall Woods Preserve in Bath. She emailed one day after listening to a recording, “…very nice to hear hermit thrush and blackburnians calling pretty much throughout, and a short but lovely interlude from a Veery…Looking forward to actually seeing the habitat at the site, although I think I can guess what it is based on the birds I’ve been hearing in the recordings from there!”
And consider comments by Bob Duchesne, author of the ‘Good Birding’ column in the Bangor Daily News and Vice President of Maine Audubon’s Penobscot Valley Chapter. “Honestly, I could picture the habitat –and even the time of day – just by the species of birds singing. Truth is, you can actually hear what a forest looks like.” And what did Bob ‘see’ in the forest by listening to recordings from forests managed by our project partners including Kennebec Estuary Land Trust (KELT), 7 Lakes Alliance (SLA), Midcoast Conservancy, and Stanton Bird Club? Here are two pictures he painted for us:
“. . . It sounds like the microphone was placed in a predominantly beech grove. (The black-throated blue warbler sang for the whole two hours.) It was on a pond large enough to have Canada geese, but the microphone was at the shallow marshy end, hence the American bittern, the unusual green heron, and the northern waterthrush that would NOT shut up. A pine warbler tells me there were pines about 100 yards away. The uncommon red-bellied woodpecker says it was likely south of Augusta. There’s some open edges not too far away, hence the whip-poor-will at dawn. The turkeys say it wasn’t very thick woods. The talkative chipmunk agrees.”
“The survey point is dominated by white pines. (Several pine warblers sang for the whole two hours.). Not much balsam or other non-pine conifers – no blue-headed vireos heard. Definitely mature – eastern wood-pewees and red-eyed vireos never shut up… In the forest, but on the edge. No edge warblers heard, but chipping sparrows piped up sporadically in the distance . . . No blackburnian warblers heard, so the recording site is likely not in the thick oaks of that property. Good understory, as witnessed by the ovenbird. The hermit thrush agrees. Cardinal and titmouse nearly constant, so generally a southern Maine sound.”
I mean, wow, right?! That’s a lot of information about a forest being belted out through the love songs and calls of the forest inhabitants. By a lot of measures, song meters have improved our ability to hear birds, for longer and more consistent periods of time than is often possible through field surveys, at hours when humans aren’t normally in the forest, and in the absence of any influence that a human presence might have.
Even among highly skilled birders, the use of song meters has led to some new discoveries and different ways of hearing the forest. Ron Vasaturo discovered a tip for identifying the Yellow-bellied Sapsucker: “If you slow down a recording using, say, Raven Lite, one hears its distinct double tap through most of the bird’s drumming. Kind of hard to catch in the field, especially since the first note is stronger than the second it drowns out the latter.”
Dan Gardoqui of Nature Serve heard the night song of the Ovenbird for the first time after decades of birding because the meters were able to record the true early birds, before even the early-bird birders are normally having their first cup of coffee. Before listening to the recordings, Bob Duchesne had never heard a Brown Creeper vocalize for two hours straight and also noted early on, “On both the recordings I’ve done so far, I heard chickadees singing “hey sweetie” quite a bit, but not doing the “chickadee” call. If there are no people around to cause alarm, I wonder how often they really call in the wild?”
There are, of course, some important disadvantages to having a machine recording versus the informed judgment of an experienced birder in the field. As Duchesne described in an article about his experiences with the Song Meter Project,
“The monitors are sensitive, and can pick up quiet bird songs at a distance. But what happens when a loud bird decides that his favorite singing spot is on the branch directly above the microphone . . . When you’re walking in the woods, you can hear quiet birds by just walking away from the loud ones, or turning your head, or cocking your ears. You don’t have those luxuries with a stationary microphone . . . Furthermore, there are no visual clues. Pine warblers and chipping sparrows both trill, but not usually from the same type of location. The warblers generally stay up high in pines. The sparrows are often on lower branches of deciduous trees. A quick glance at the trees will often aid the identification, but there’s no glancing option on a tape.”
Bob was certainly not alone in reporting the challenges. Take Margaret Viens, an eBird reviewer for Kennebec and Androscoggin Counties, on the Maine Bird Record Committee, and a contributor to the Night Jar and Owl Breeding Bird Atlases. She reflected, “even though I do bird by ear in the field, I have never ‘JUST’ birded by ear, as if ‘blindfolded’…I think I identified at least 23 species in the 2.5 hour recording, with sometimes 4-5 species calling/singing at the same time and some vocalizing the entire time, making it a challenge to ‘block’ out some species while trying to pick up others”.
But even with those challenges, thanks to the contributions of more than 40 people, we have been unraveling what over 100 species have to tell us about the forest where they are seen or heard. Just by their presence, their locations, and their vocalizations, birds are helping to inform the practices that we convey to loggers, foresters, and private woodland owners to help them manage their forests in ways that benefit birds and other wildlife.
The more I think about it, the more I am starting to think I wasn’t truly seeing the forest for the trees, or should I say, for the birds, at the outset of this project. I missed the full scale of what could emerge through the act of placing a few green, hard plastic boxes out in the forest and switching them to ‘on’.
First there’s the compilation of knowledge about the species present, the habitats they use and frequent, and the status of conservation management within the demonstration forests we were observing. We’ve also learned a lot about the pluses and minuses of the various methods for collecting and processing bird data—be it field counts or song meters, human listeners or audio analysis software. And then there were the connections made between birders, between organizations, and local communities, which sometimes spiraled in new directions and into new conservation partnerships.
Even two years later, we’re working closely with our land trust partners to further education about bird-friendly forest management and we continue to collaborate on forest management approaches. We’ve learned about similar song meter efforts and worked with other organizations on ways to process the recordings. And some of the land trust staff and birders involved in the project are also now contributing to other Maine Audubon efforts. For example, Anna Christie-Carnicella joined the Annual Loon Count after connecting with us on the Song Meter Project and wrote on her survey form about a magical experience with her young daughter on a foggy morning loon count. Earl Johnson first helped with the software analysis in 2020 and this year joined Maine Audubon’s Loon Restoration Project as a seasonal staff member. And Chris Schorn helps provide protections for loons nesting on some of the Midcoast Conservancy islands.
So, the Song Meter Project benefits Maine Audubon’s FFMB Program—and hopefully Maine birds—by helping us determine the importance of various habitat features to forest breeding birds and particularly 20 species of conservation concern. It also helps us decipher how to better track birds’ associations with different habitat components.
I didn’t anticipate at the outset how much the project would also benefit the birders, land trust staff, and volunteers who contributed hundreds of hours to the project. We’ve heard from participants that it has honed skills, provoked new thinking, built information to help the conservation work of our partners, furthered forest outreach efforts, allowed people to listen to birds even in the winter, and brought people together—all while offering new opportunities to contribute to forest and wildlife conservation.
That’s seeing the forests for more than just the trees! In what this project has revealed about forest communities, as well as the connections with human communities, I’m certainly seeing forests a whole lot clearer these days!
To read some additional articles written about the Song Meter Project by our partners and participants:
- Spring ‘birding by ear’ is a fun activity many can do right at home. Bob Duchesne. March 25, 2020. Good Birding, Bangor Daily News. Available online:
- Spotifly: Snags, Songbirds & Soundtracks. Chris Schorn. The Drift. Spring 2021: 6(1). Midcoast Conservancy.
- A Nocturnal Courting Mystery. Dan Gardoqui. February 14, 2020. Lead with Nature Blogpost.