I never saw or heard either of the nuthatches again. To find out what had happened, I removed a slab of wood from the side of the log to reveal the nest inside. It was a mere ten centimeters down from the tiny entrance hole. Made mostly from soft cedar bark fibers and some fluffed grass, it did not contain hair or a single feather. Curiously, I saw no eggs and no young—not even the depression of a nest cup.
Knowing the nest could not have been empty all this time, I removed some of the nest material. And there, under the fluff, lay six tiny brown-spotted eggs. I opened one and found a partially decayed embryo.
Normally the eggs would not be covered unless the incubating bird expected to stay away for some time. This meant that the female, who had been the sole incubator, had apparently deliberately covered her eggs before leaving them. And she would have done that only if she had been very hungry and expected to be looking for food for an extended period. I concluded therefore that the birds had abandoned the nest because they had run out of food; he had been unable to feed her, and she had been forced to go into the forest to forage for herself.
Red-breasted nuthatches normally live in coniferous forest, but here they were out of their usual range. There were no spruce here, no fir, and the few pines now had no seed. Once my birdfeeder was empty, the only likely or possible food was insects, and they would not have been active during the three drenching and cold days.
For humans as for birds, making a home requires more than a house. These nuthatches had made themselves a place to live, but it was insufficient without a sustaining home environment. Like the sunflower seeds on which the nuthatches had staked their survival, our food supply is risky: it comes from very far away. But sunflower seeds at a feeder are perhaps more predictable than much other bird food can be.
Some years all the spruces in an area are loaded with seeds, or the oaks and beeches are bearing fruit in abundance, but in the next few years they may be barren. With no consistently predictable time or place to go, what then? What if you are a finch, a red-breasted nuthatch, or a blue jay and your seed crop is absent one year? You could move and trust your luck, or stay and make flexible decisions. To make good choices requires intelligence. Blue jays, members of the crow family, are thought to have that in spades.
9
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Blue Jays in Touch
BLUE JAYS’ INTELLIGENCE AND ABILITY TO TALK HAVE LONG been of interest. Mark Twain broached the topic about a century and a half ago in his famous short story “What Stumped the Blue Jays.” The first sentence is assertive and authoritative: “Animals talk to each other, of course, there can be no question about that; but I suppose there are very few people who can understand them.”
Twain’s protagonist, Jim Baker, a “middle-aged, simple-hearted miner” from the mountains living “in a lonely corner of California,” believes that blue jays talk to one another. He tells of a jay that started to fill a knothole in his cabin roof with acorns. Finding the task difficult, it recruited friends to help, and the flock proceeded to fill the entire cabin with acorns. Despite having reservations about the veracity of parts of this tale, I do believe that blue jays talk to one another. I just don’t think they speak English.
At dawn one day in late April 2007 I was seated and partially hidden in the branches of a pine tree. A pair of blue jays loitered nearby, making soft calls below me in still-bare viburnum bushes. The male approached his mate, and she began to imitate a baby bird, flapping her wings and opening her bill. He understood and placed food in her mouth. She then broke a dry twig off the bush and they both flew to the nest they were beginning to build in a small spruce in the forest. Six days later, while pulling rootlets out of the ground for the nest lining, they made soft, fast-repeated squeaky sounds. Their calls seemed like whispers, meant exclusively for each other, in stark contrast to the jays’ usual exclamatory screams.
The jays’ loud scream calls are given both singly and in sets of several in succession. Volume and nuances of pitch and rapidity of succession vary. Jays are commonly assumed to be scolding, like the other highly vocal familiar animal of the north woods, the red squirrel, which will chatter and stamp its feet on a branch above you if you enter its territory—not a welcoming display. The main difference, it seemed to me, was that the blue jay does not stamp its feet.
On hearing a distant jay’s scream I often wondered what the bird was excited about. My guess was that the jay was agitated by an owl, a deer, a fox, or some other animal. I often tried to get confirmation, but although jays do mob owls, I was rarely successful in finding anything at all. However, deer and other woodland animals are both common and often difficult to see, so the hypothesis that the jay was announcing a woodland creature was difficult to disprove. The birds kept moving, too, so that by the time I got near the site of a scream both the jay and the supposed object of its screams were long gone, or there had not been any object in the first place. It was probably the latter: in many hundreds of times of watching a screaming jay I did not see any likely cause for alarm or comment near it more often than expected by random chance, nor was I ever scolded by a jay except at its nest. In contrast, I’ve been scolded by red squirrels on probably hundreds of occasions. If a human venturing near a jay is not scolded, why would a jay scold a deer, a moose, or any other large animal passing through the woods?
Having no idea what most of the blue jays’ screams meant but suspecting they must mean something beyond attracting other jays to mob an owl or a hawk, I tried to get clues by looking systematically as occasions presented themselves. Although over the years I had taken copious notes of when and where blue jays called, I had found out little except that they were much more apt to call when perched than when flying. Also, they were overwhelmingly most likely to be seen singly, and secondly in pairs. To get some numbers to document that impression, I watched them both in my woods and on road trips. I recorded 168 sightings of singles. Next most common were pairs (32), followed by triples (10), and foursomes (4). Many more stationary birds were heard but not tallied.
My observation that blue jays usually called while perched and alone seemed odd. In most species of birds the crowds are often conspicuously and sometimes continuously noisy while in flight, whereas these jays were usually silent in flight. Ironically, on rare occasions (as I will describe in detail later) they aggregated into groups, and then they were either very noisy, or silent, depending on whether they were mostly perched or in flight. Why would they scream when they were alone, yet be noisy in crowds? The specifics and contexts of their vocalizations mattered, but which ones?
Unusual encounters with jays in the wild were opportunities for natural experiments, and one happened while I was pushing my way through a thicket of young alders and pines. I suddenly saw at near eye level a blue jay nest with a parent’s tail sticking out at one end. The jay faced me point-blank, and screamed at me. In seconds its mate arrived and began scolding me as well. The racket had a result: within a minute six other jays gathered nearby in the tall poplars and maples. They started bobbing their heads and making both rattling and two-note, flutelike calls that contrasted with the excited screams of the pair next to me.
The varied vocalizations of the six new arrivals, however, did not sound like warnings. I suspect these newcomers saw that I was not one of the jays’ archenemies, an owl or a hawk, that they might have expected when they heard the nesting pair’s excited warning screams. Seeing me instead—a human, standing very still and not doing any harm—may have confused them; they dispersed almost as quickly as they had come. The nesting pair stayed. I still didn’t move, and then one of them left as well.
The vocalizations of the pair at the nest with young had been aimed at me, as a warning to a perceived potential predator. The six other jays that had been recruited by their noise had provided no apparent help, except possibly communicating to the pair through their behavior that I was not a threat.
Do blue jays routinely come to another’s nest if the nest owners sound
an alarm? To make another test, I left the nest vicinity and came back a half-hour later to find out if the previous scenario would be repeated. Again only one of the pair was present, and this time it was not agitated. I was able to reach into the nest and touch the three almost black, featherless young without causing a ruckus. The parent that was present screamed only once or twice, shook its feathers once, and pecked at a branch, but soon appeared much calmer than before. I watched for another ten minutes, and after a while the jay seemed at ease and left. I left as well, planning to return later to deliberately induce the pair to again scream an alarm to see if the six others would make a second appearance.
When I approached, one of the parents was again on the nest. Again it flew off, and this time to provoke it I lifted one of the young out of the nest. This ploy worked: the parent confronted me up close and scolded me even more vigorously than before. The mate came instantly and gave short high-pitched, two-note calls plus rolling, liquid-sounding double cries with an undulation in each. Having no idea what they meant, I stayed and waited for further developments. The calls became louder, longer, higher-pitched, and more repetitive, and one of the pair flew so close to the back of my head that I felt a rush of air from the wing beats. It then showed its anger in front of me by hammering limbs and ripping leaves off branches. Since no harm could come from my presence as such (the myth that young birds will be abandoned if touched notwithstanding), I stayed for at least ten minutes, during which the pair’s scolding never ceased. I heard no responses to the parents’ alarm calls from other jays in the woods. I repeated the experiment/observation twice more on subsequent days and again eleven days after the first encounter, by which time the three young were feathered out, and each time I got the same negative result. Although these results don’t fit the picture of jays’ being attracted to others’ alarm calls, they do not contradict it. The six could have been a group passing through, or if local birds they might have learned what the pair was excited about and lost interest in me.
Some species of jays have helpers at the nest (usually offspring from previous clutches) that assist a pair in protecting and rearing young—but none had been reported for blue jays. I now felt confident that there were no helpers defending this nest, and I was also sure the six jays that had been attracted to some of the pair’s alarm calls had not come to help. The jays’ investigation of alarm calls was information-gathering behavior: by finding out what had caused the alarm, they learned what had threatened other jays and thus should be watched closely or avoided. In contrast, the attraction of the mate and possible nest helpers to such calls is mobbing—ganging up on predators to chase them away. I suspect also that the so-called funerals attributed to jays that gather near a dead individual are a variation of, if not the same thing as, one of these responses.
My observations at the blue jay nest, and similar ones of a red-tailed hawk and a barred owl, convinced me that the jays’ screams can act as powerful attractants, as the well-known lore suggests. But that does not explain why the thousands of other blue jay screams I’ve heard in the woods did not attract a crowd or even any individuals. Different meanings are attached to different calls, and a large part of the explanation could be variations in the calls—their volume, inflection, repetition frequency, pitch, and other nuances—that were beyond the scope of my methods and scale of investigation.
Blue jays also form another type of aggregation, one that is associated with excitement of a different kind. This excitement occurs only on the first warming days of early spring, from late February to late March, when blue jays get together, sometimes in large numbers, and spend hours in social palaver.
The few of these spring palavers that I have witnessed involved from eleven to more than thirty jays and lasted from several hours to most of a day. However, it may be that I usually saw these assemblies only at their peak, as I did at 9 a.m. on April 18, 2007, when twenty-five blue jays quickly gathered in the very tops of tall bare ash trees by a clearing on a hill. I watched in amazement as jays screamed, made rattling noises and bowing displays to one another, and flew around in small groups for a couple of hours. I had not seen much of the buildup to that blue jay convention. But one that occurred directly at my cabin on March 8, 2014, had a two-day lead-up, during which I was able to gather information about how it had started.
March 6 was one of those idyllic pre-spring Maine mornings, cold but clear. The sun was bright under a cobalt sky over a deep blanket of snow, and the trees were still bare. No jays were at the feeder at 7 a.m., so I was surprised to see six arrive in one group and land together in the top branches of a large spruce at the edge of my clearing, where they stayed silent and hidden in the thick branches. Strange, I thought. I waited a half-hour and neither saw nor heard anything. Could I have missed their leaving when I turned to put wood in the stove? I needed to know. Taking my axe to bang on the tree to flush them if they were there, I walked on the snow crust to the tree—and just as I reached it the birds flew out and scattered into the woods. Soon I heard jay talk spread well over a square kilometer, and the talkers included more than six birds.
Two days later temperatures had risen to 45°F, the warmest day of the spring so far. The sun was bright, and blue jays were suddenly in abundance near the cabin. One landed on the tiptop of the same spruce in which the six had perched silently, but this one called. Soon jays were sounding from the forest all around. Groups of two, three, or more began flying into my clearing and perching on the tops of the leafless maple trees. In twos and threes they bobbed up and down in what looked like pushup exercises, accompanying this display with a cacophony of high-pitched, double-note calls so close together that they almost sounded like one. They also made long rattling calls and at least six other distinctly different sounds. By 8 a.m. they were gone.
At 11:05 a.m. a group of eleven jays flew in, making a racket as during the earlier displays. Many of them were now in pairs, which perched together, performed vigorous pushups, and gave even more kinds of calls. By noon all had dispersed into the woods, where most of their calls reverted to the usual screams. Since jay palavers of this type occur only in the spring, a month or so before nesting, they probably function as mate marts, where single birds meet, display, and maybe size each other up and form pairs.
Blue jays also form large aggregations for reasons other than mobbing, bobbing, or mating. In April 2012 I saw seventeen flying together over the forest. And on May 19, when the pairs were busy at their nests, I sighted a larger flock than ever before: twenty-nine flying along silently in a ragged group. At that time of year, they were unlikely to be current-year breeders, nor could they have been the year’s young.
Fifteen months later, on August 12, 2013, I chanced on a similar sight near my cabin. The sky was overcast, and it was late afternoon. I had not heard blue jays for weeks, but now a flock of about twenty-five flew over me. Like the other traveling groups, but unlike the jays at the spring conventions, they were silent. However, in the next weeks I often heard blue jays in the forest. At that time in late summer there were no acorns and no beechnuts, their favorite foods and/or staple diet in the fall. The first red oak acorns would within a week or so become available in isolated patches of forest. Maybe it was their time to go find them. Tree seeds and fruit are usually available in widely dispersed patches, and the birds feeding on them—finches, robins, and waxwings—travel in groups that provide many eyes and likely allow easier discovery of the patches, where the food’s abundance reduces competition. The same principle may apply to blue jays’ forming flocks for long-distance travel to find seasonally patchily distributed food.
Over a period of twenty-one years I eventually saw eighteen such flocks of silent birds flying low over the forest. Ten were in the spring and eight in the fall. I could not detect any pattern among them with respect to size, which ranged from five to thirty. The direction of travel was north/east in the spring and south/west in the fall. However, sightings were highly sporadic, and since I do not n
ormally carry a compass, I gauged direction by eye. Also, since the birds flew low I may not have been able to see all of them; the numbers are minimums.
What moves out can also move in. By May 25, 2014, a crowd appeared to have arrived. After that day I heard jay calls from all around my cabin and saw jays flying, as singles and pairs, “everywhere.” During an outbreak of small black beetles feeding on young tree foliage, I sometimes saw up to four in a tree at one time. A number of jays came to the birdfeeder, but given the calls in the surrounding woods, they were the minority. By May 30 there was still lots of jay activity in the vicinity. Jays were everywhere; I saw them in twos and in loose groups of several traveling together, and heard much chattering. From dawn until late afternoon their voices sounded from all sides of the clearing and far into the woods. The many different kinds of calls, with their various nuances, pitches, sequences, and frequencies, amazed me.
Blue jay numbers relate to the availability of food, which can be highly sporadic. In the fall of 2013 the beeches bore seeds, and on September 7 I saw jays after not seeing any in residence for months. Then on the afternoon of September 12 I heard a sudden and very localized clamor from a group of blue jays. I stalked into the woods to find the cause of the commotion, but could not discern a focal point such as an owl. Two jays would fly in one direction, three in another, while two more loitered near me; others were hopping around in a maple grove, and still more were scattered in spruces. Whenever some were together they made relatively soft calls. A half-hour later, as the jays dispersed broadly, I approached from another direction and encountered more excitement. Most of the jays were in dense forest where they could not have been in visual contact with each other. It seemed that their vocalizing might have simply been related to keeping themselves oriented to one another in a convention or social gathering. After that there were often several jays together at the beech grove nearby, but there, while gathering the nuts, they were almost always quiet.
One Wild Bird at a Time Page 9
