One Wild Bird at a Time
Page 1
Contents
* * *
Title Page
Contents
Copyright
Introduction
Flickers in the House
A Quintet of Crows
Getting to Know a Starling
Woodpecker with a Drum
Barred Owl Talking
Hawk Tablecloths
Vireo Birth Control
Nuthatch Homemaking
Blue Jays in Touch
Chickadees in Winter
Illustrations
Redpolls Tunneling in Snow
Tracking Grouse in Winter
Crested Flycatcher’s Nest Helpers
Red-winged Blackbirds Returning
Phoebe Seasons
Evening Grosbeaks
Audience to a Woodcock
Acknowledgments
Further Reading
Appendix
Index
Sample Chapter from NATURALIST AT LARGE
Buy the Book
Read More from Bernd Heinrich
About the Author
Connect with HMH
Text and illustrations copyright © 2016 by Bernd Heinrich
All rights reserved
For information about permission to reproduce selections from this book, write to trade.permissions@hmhco.com or to Permissions, Houghton Mifflin Harcourt Publishing Company, 3 Park Avenue, 19th Floor, New York, New York 10016.
www.hmhco.com
Library of Congress Cataloging-in-Publication Data
Names: Heinrich, Bernd, date, author.
Title: One wild bird at a time : portraits of individual lives / Bernd Heinrich.
Description: Boston : Houghton Mifflin Harcourt, 2016. | Includes index.
Identifiers: LCCN 2015037246 | ISBN 9780544387638 (hardcover) | ISBN 9780544386402 (ebook)
Subjects: LCSH: Birds—Maine—Anecdotes.
Classification: LCC QL684.M2 H45 2016 | DDC 598—dc23
LC record available at http://lccn.loc.gov/2015037246
Portions of Bernd Heinrich’s “Chickadees in Winter” first appeared in Natural History Magazine.
Cover artwork © Bernd Heinrich
Cover design by Jackie Shepherd
Author photograph © Kyle Isherwood
v2.0318
Introduction
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AS A CHILD I HAD JACOB, A PET CROW. I ROAMED THE WOODS hunting his food—frogs, field mice, caterpillars, beetles, and grasshoppers—and feeding him by hand. But wild birds remained out of reach. Much later my vocation and my passion led me to try to answer specific questions about what animals do and why. The protocol for my investigations required eliminating both random chance and individual differences. However, both of these are important parts of life, not peripheral to it, and the goal of biology is to understand life in nature. In this book I hope to celebrate individuals as they presented themselves during my encounters with them in the wild.
My quest to understand what could be gained from intimacy with wild birds was kindled by an incident in Africa.
Along a dusty dirt road on a hillside in Kenya, I viewed Lake Nakuru with its million pink flamingos and thousands of white pelicans. It was a scene and a palette, beautiful but remote, that made me aware of myself as a tourist in alien territory. But then with a jolt I saw a glimpse of another Eden in the nearby bushland.
Among acacias near the lakeshore, birds were mingling with the most fearsome mammals on Earth, the powerful and aggressive Cape buffalo. Oxpeckers (a species of starlings) were riding on their backs, while cattle egrets accompanied them underfoot. Blue rollers swirled over their backs hawking insects, and emerald-green sunbirds foraged from red flowers close by. Most wild birds stay separate from humans, yet here many acted as if the buffalo were just part of the scenery. For a moment, putting humans in the place of the Cape buffalo, I wondered: What if all birds treated us like this, or as Jacob had treated me? One of the reasons the world can be exciting and beautiful for us is that perhaps we alone have the capacity to enter vicariously into the worlds of others through knowledge leading to empathy. When getting to know a bird—by learning where it lives, what it eats, how it forages, where and how it nests, what it fears, and in general what it likes and dislikes—we are entering another world. Each animal gives us a new view, a new experience, that involves stepping out of our own world into another, and it is always an adventure.
Birds brighten our days by their otherworldly songs, their visual beauty, and their astonishing behaviors when they are able to be themselves in their natural environments. Our usual distance from them makes it difficult for us to identify and isolate individuals, much less keep track of them in the wild where they conduct their lives. Prying meaning and intimacy from them usually requires long-term and technically difficult studies. Traditionally these have involved attaching leg rings or wing tags of different colors and numbers, or monitoring individuals with electronic devices. Most of these methods are inaccessible to amateur biologists, and in fact only a few professional ornithologists use them. Aside from certain obvious exceptions, the observations discussed in this book were of wild birds unencumbered by devices; I describe a relationship with wild birds that is available to almost anyone anywhere.
My watching birds of a particular species was usually stimulated by an anomalous observation that sparked a question. I followed leads as they presented themselves, waiting for dots to connect and make an interesting pattern or a tentative hypothesis, which then might lead to a tentative revelation. The leads, the twists and turns, made adventures that I have tried here to preserve in written and sometimes literal sketches.
Most of the material for this book was gathered in or near a clearing in the Maine woods next to the cabin where I now live. Large windows in all directions make this home a live-in bird blind. My outhouse with an almost equally panoramic view serves as one as well. The clearing where the cabin stands, an island in the midst of forest, has an abundance of berries, seeds, and insects not found in the closely surrounding woods. As a permanent resident with no radio, television, or other electronic distractions except e-mail, I engage with my avian neighbors, visitors, and vagrants, and keep daily records throughout spring, summer, fall, and winter.
I hope in One Wild Bird at a Time to reveal details of birds’ everyday lives as seen by direct observation, and while I hope also to capture something of the adventure of the chase, this book is less about research results than about the reasons I “do” research. It is aimed to be as realistic as science demands and imaginative enough to suggest possibilities that science allows.
1
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Flickers in the House
MY SUMMER SPENT OBSERVING BIRDS SEEMED TO BE WINDING down. Most of them had found mates, made nests, and incubated their eggs; feeding the young was now their main preoccupation. I had finished a marathon observation of a pair of tree swallows. My phoebe had this year not attracted a mate. The blue-headed vireos’ story was finished for the year: one nest I was watching in a balsam fir tree had fledged four young; the other had been abandoned after a gradual decline in the number of eggs in the nest. The sapsuckers with their “super drum” on the apple tree had stopped drumming and were now incubating or feeding young. I was starting to feel relaxed enough to sit and write. But there are always distractions.
Next to the window of my cabin is a paper birch tree. It had grown at the edge of the old cellar hole with collapsing stone foundations that I rebuilt to put my cabin on. Each year it hosts aphid colonies tended by red ants that live in the cabin’s roof space. A highway of ants up and down the white bark attracts a pair of yellow-bellied sapsuckers. Just three meters from me as I sit on the couch writing,
these beautiful woodpeckers unobtrusively and silently lap up ants from a trail with traffic both up and down.
Hearing a woodpecker tapping from the cabin wall opposite the birch tree wasn’t particularly surprising to me; I assumed one of the sapsuckers was temporarily distracted from the ants and had started sampling wood. Strangely, though, on several occasions when I opened the door to look I saw instead another woodpecker fly off: the northern yellow-shafted flicker. After a time I noticed a suspicious rhythmicity to the tapping. Flickers feed on ants, too, but as far as I knew, they foraged for them on the ground.
A day later, on June 8, I got out of bed at 4:30 a.m. to write up some raven observations from the day before. A little later I heard the same rhythmic tap, tap, tap, tap, tap from the same cabin wall. Surely the noise would stop soon. At 6 a.m. it still had not let up, but my patience had, so I gently opened the door to peek around the corner, and again saw a flicker leave. This time I noticed a small hole almost through the wall’s outer pine boards: the flicker had apparently been making a nest hole. But the outer and inner cabin walls are separated by a ten-centimeter gap, so if the flickers (I assumed it would be a pair) penetrated the outer board they would meet a bottomless space, with no place to put their eggs.
The next morning at 5:10 a.m. I heard a rustle on the wall, then a light tapping changing to vigorous hammering, which continued nearly unabated for two hours, finally stopping when a second bird arrived. A period of silence was followed by five separate soft, second-long drumrolls, probably some sort of signal. Then total silence. Had the pair gotten through the outer board?
The hole was now nearly large enough for them to slip through, and I was afraid that when they discovered the empty space they would leave and make a nest hole elsewhere. The opportunity to have flickers nesting in my cabin was too good to pass up. I had to do something to help make it happen, and I had to do it without the birds noticing me, in the few minutes they were away.
The potential nest site was too high for me to reach from the outside, but I calculated where it would be on the upstairs bedroom wall. With my chainsaw I removed a section of the inside wall covering its anticipated location. I fixed boards to the bottom and sides below the entrance hole to create a possible nest cavity, cushioned its floor with sawdust and woodchips, and had barely swept the sawdust from the floor, bedding, and clothes and settled in downstairs to wait when the tapping resumed.
By midmorning the flicker was in the house, or to be exact, in its east wall. By afternoon I heard scratchy noises there but no more tapping. The scratchy sounds plus occasional very light and brief tapping continued into the evening and resumed at 5:10 the next morning, and again continued for two hours and stopped when a second bird flew to the wall. As before, I heard the signal drumrolls, which sounded like fingers running over the teeth of a comb. Then all was quiet. I was happy: I knew now that the flickers would stay to nest.
At this point I was not yet living full-time at the cabin, and left it for a few days. Returning on June 16, I was eager to see if I could call it not just the Tree House, as I had until now, but the Bird House. It was the latter! As I walked toward the cabin, a flicker flew out of the hole in the wall. I rushed upstairs, removed the loose panel I had left over the cavity, and looked into the nest. To my joy, on the sawdust and wood chips lay a clutch of seven pearly white eggs.
Flickers normally take about two weeks to excavate their nest cavity, and the male does most of the work. However, the female determines when to lay and how many eggs. Apparently the time until egg laying is not measured from the beginning of nest-hole construction, because this pair had a suitable nest cavity in only three days and egg laying began then. The trigger for the physiological changes of egg production and laying thus appeared to be related to timing of nest-hole availability.
My flickers stopped at seven eggs, a normal clutch size. But that number is below what the species can produce. Flickers are, like chickens, indeterminate egg layers; removing one egg from the nest while leaving at least two in it induces the female (provided she has enough food) to replace the egg. In one case a flicker kept laying until she had produced a total of seventy-one eggs, all the time apparently perceiving she only had about five—not yet a full clutch.
I found the flickers’ incubation time peaceful and satisfying. It was a comfort at night to think that a flicker was sitting on her seven eggs about three meters from me, sheltered from the weather. On nights when the pounding of the rain got louder and louder until it became a roar, I felt good that both of us were high and dry.
One early morning after the rain stopped I heard a soft rustling from within the woodpecker hole, then some brittle scratching sounds and several fluttery vibrations. Something was happening. Listening closely with my ear to the wall, I thought at times I was also hearing faint whispering and cheeping-churring voices.
At first light I looked into the nest and saw a heap of tiny naked pink bodies, with empty eggshells scattered among them. The babies made a scratchy-sounding purring noise, except one that made high-pitched peeps.
The sounds they made were the weirdest, most otherworldly I’ve ever heard, and the most improbable. If I had to describe them I’d say, “Just like you’d expect baby pterodactyls to sound, only cuter.” And for that matter, the little pink bodies with their tiny heads on long snakelike necks probably didn’t look much different from reptiles either.
In order to watch the birds from up close without their knowing, I covered all the windows to darken the bedroom and inserted a pane of glass into my viewing hole. Later I sometimes removed both the board and the glass and set up my camera in front of the nest to take pictures. At first the parents seemed not to notice that the back wall of their nest was missing, but then they inspected the cavity from top to bottom as though looking for something. They also hung by their feet from the lip of the cavity and looked around my room. I sat frozen in front of them in the dark.
Baby flickers before and after they begin to develop feathers.
Three days later the chicks had grown noticeably, but they were still surrounded by eggshells. Most parent birds remove shells as soon as, or even before, all the eggs have hatched. This is an evolved anti-predator strategy; even eggs that are well camouflaged with pigments on the outside are white on the inside and therefore conspicuous enough to attract predators if left near the nest. But in a deep nest hole there is scant need for camouflage and thus no rush to destroy the evidence of hatchlings. The eggshells may be ignored, or in time eaten or trampled down.
During the two nights after hatching (July 3 and 4), the babies made upward-inflected whining calls—I suspected they were hunger/begging calls—all night long, reminding me of a flock of bleating goats. The sound was not soothing, and I plugged my ears trying to block it out. I did not know if there was a parent in the nest, and I didn’t yet dare to look into it at night to find out, because that would alarm a parent if one was there. The skin over the hatchlings’ eyes had not yet parted, but they would have reacted to almost any vibration by stretching their scrawny necks to beg for food. On the night of July 4, when I was fairly sure no parent was with them, I finally did check several times, and there was indeed never any adult present, but they were as noisy as before.
By July 5 their eyes were starting to open. They still bleated occasionally at night, but the sounds were softer and their piping choruses were separated by long silences. After a few more days they began to be quiet all night long. The parents’ hygiene behavior at the nest changed too. At first they had picked up and swallowed the young’s feces. By the fifth day, the poops were the size of hazelnuts and wrapped in neat membrane-bound packages. The parents no longer ate these fecal packets but picked them up and carried them out of the nest.
The babies’ necks seemed grotesquely long and snakelike even before their eyes had opened, and the instant an adult blocked the light at the nest entrance, all their heads shot up and in a chorus of scratchy-churring voices they begged to be
fed. The parents delivered food by thrusting their bills into their offspring’s gaping mouths and vibrating their heads in a jackhammer-like pumping motion as they regurgitated food deep into their offspring’s throats. Each such transfer took about two seconds, and during any one visit the parent might make a dozen or more transfers, distributed to several chicks. In the melee of weaving heads I had no way of knowing how much food was being transferred or how many times any one chick was fed.
An adult flicker inside the nest in the cabin wall, looking outside.
Flicker delivering food to nearly full-grown young.
Flicker reaching between young searching for fecal droplets.
This “bill-into-mouth” feeding protocol also made it nearly impossible for me to see what kind of food the parents brought to their young. But occasionally I saw spill along the sides of their bills during food transfer, and it seemed to be white ricelike objects. To find out what it was, I followed a standard ornithological method of assessing birds’ food. I moved the chicks from the nest to a dark box, loosely wrapped rings of pipe cleaner around the necks of two of them, and replaced them in the nest. Now after the two ringed chicks were fed the food would be detained in their mouths rather than immediately swallowed. Seconds after one of the pipe-cleaner babies was fed I retrieved it and checked the contents of its mouth: a bolus consisting of 140 larvae, 29 pupae, and 47 adult ants.
That sample may or may not have been numerically representative of all payloads these flickers brought back to the nest and fed to one chick, nor were the thirty-two trips the parents made on one day necessarily average. But using these numbers as ballpark estimates indicates that the eventual twenty-two days the babies were nest-bound involved nearly 700 feeding trips, or 100 trips to rear each of the seven young, or about 21,600 ants to fledge one flicker.