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Mind of the Raven: Investigations and Adventures With Wolf-Birds Page 4
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We had other questions. I previously had found that recruitment normally brings the entire nocturnal roost of thirty to forty or more birds, who can strip a deer carcass in a day or two. Why then isn’t a territorial pair more tolerant of a few vagrant juveniles who happen to find the carcass, so that there is no need for recruitment? Why don’t they tolerate a couple of strangers at the dinner table rather than excluding them, thereby risking their bringing back a mob who will take everything? (I would later find with Goliath and others that adults at times do indeed tolerate another bird or two.)
I walked up the path to the cabin under an absolutely clear, moonless sky filled by the swath of the Milky Way, with the constellations etched brilliantly against the heavens.
The next morning, as I walked back down in the dark to resume my vigil in the spruce blind, there was a heavy, somber overcast. I had awakened at 5:00 A.M. to the ring of the alarm clock, and built a wood fire to cook my oatmeal and boil a cup of coffee, resisting the temptation to enjoy breakfast at leisure. I sat by the fire for a while before hurrying through the woods, driving to the other end of the lake, and hiking into the woods again, trying to make it to the blind before the first hints of daylight.
A crust of ice had formed on the twigs from an early morning rain. When I settled back into the blind to resume the watch on bird Number 837, I heard the soft tinkling of the iced branches as dawn approached with a slight breeze, punctuated by the soft, dull, rhythmic tapping of a downy woodpecker somewhere behind me.
The radio signal from Number 837 still came from the pine grove by the lake where she had ended up the night before. What a welcome sound to hear her strong signal and the swoosh of her wing-beats at 7:15 A.M.! She arrived alone and silent, hopped from branch to branch, descended to the meat pile, and as with the day before, immediately began to feast on fat. She spent the next four hours making food caches. Unlike the previous day, she usually flew rather than walked to many of her cache sites, although her radio signal indicated she didn’t fly far. As expected, no crowd of birds came. I started to lose some of my enthusiasm. The cold was gnawing at my feet.
Things picked up at around 11:00, when a pair (the pair from yesterday?) finally returned. I suspected that their territory, or their main feeding site at this time, was distant, since they arrived so late. The male gave a long series of undulating territorial quorks, and his mate gave slow measured knocks in series of three—knock, knock, knock—knock, knock, knock. Number 837 then disappeared from sight for three and a half hours, but from her radio signal I knew that she was still in the nearby forest. I heard her beg a number of times—indicating that she was being aggressively confronted by another bird.
At 2:30 P.M., it began to rain harder. The thick fir boughs of my blind held out the light, but they did not hold out water. I was thankful when it soon got dark and was time to go home. The adults had left long ago, but 837 still remained nearby in the woods.
I again stopped by to see John up in his tall spruce tree. He told me that the birds had again regrouped nearby, after coming from the same direction as yesterday. Our bird was sleeping separately from the crowd, at the same place she’d slept last night. We thought she might recruit the next day, if she found the roost, because she couldn’t eat alone due to the resident pair.
Once in the blind the next dawn, I got out a flashlight, adjusted the antenna and dials of the radio receiver, and took my first reading. Our bird was still where she had slept. Good, I had made it up before she did. By 7:00 A.M., she was gone, and I lost all radio contact.
I waited for what seemed like an hour, then maybe another hour, but still nothing. I had no idea what would happen, which added a welcome element of excitement. The bird could come at any second, or not at all. Perhaps she had joined another group and was now twenty miles away in one of any number of directions, feeding at a moose carcass on Tumbledown, loitering at the Dryden dump, or at a coyote bait put out by hunters. Maybe the pair would come to feed. Maybe a new bird would discover the bait. This was no longer an experiment, because too many variables had already crept in, and we could not control any of then.
She finally returned, silent and alone, and she fed—fat only, although there was plenty of muscle meat—as if she hadn’t eaten in three days. In between snacks, she cached food. The first three caches were within ten feet of the huge bait pile itself.
About an hour later, her food caching came to an abrupt halt when the territorial pair returned. And when they arrived, you knew it! Before, there had been total silence. Now there was constant calling. Number 837 managed to give several “yells,” but the pair aggressively flew after her and she fell silent. The pair continued their deep, resonant, rapid-succession short quorks that said, “Get the hell away,” and they also made the long, undulating territorial quorks that said, “I’m here. Take notice.” Both birds of the pair gave each call. I was lucky to catch a glimpse of 837 trying to hide. Her red shoulder patches gave her away as she squeezed herself into the thick branches of a spruce some one hundred yards away, but she was not hidden well enough. The territorial birds found her even there, and a long vociferous aerial chase ensued, as their calls receeded into the distance. Soon all was quiet again, and the bait was deserted. Our bird was driven away—but not for long.
In twenty minutes, she was back, still alone, sleek, nervous and agitated, pecking on the branches at her feet and scanning nervously in all directions. After ten minutes, she hopped down to the meat, again eating fat as if she hadn’t eaten in days. After snacking for a while, she flew off, holding as many pieces of suet as a raven bill can hold. At 9:28 A.M., the territorial pair returned and stayed for forty-two minutes. They still did not feed, all the while giving their long “I’m here” calls. Number 837 stayed away from the bait, but my magic instrument, the radio receiver, told me with beeps that she was still near, apparently hiding. Well, most of the time. Once she gave a yell—the call that recruits. A bad move—as far as I knew, there were no ravens nearby to recruit, except the vicious adults. They immediately pinpointed her, and another vigorous aerial chase ensued.
There were no birds near for a long time after that, and I lost radio contact with our bird. Suddenly, I heard some resonant monotones from the skies far above. Knowing no birds were nearby, I took the risk of stepping out of the blind for a better view and saw what I guessed to be the territorial pair—two specks against a patch of blue sky amongst dark, drifting clouds. The two circled side by side, wing-tip to wing-tip. Occasionally, they dove and turned in formation, then ascended in circles again. Higher and higher they went, thousands of feet up. I followed them through my binoculars for as long as I could until they faded into a hole in the sky among billowing, cushiony clouds, still dancing side by side. This dance moves me more than any human dance performance ever could. This one has been performed for millions of years and will continue for a long time to come.
At 12:24, the pair returned, first making the rasping “Get out” quorks and then, for the next eighteen minutes, an almost continual series of the long undulating “I’m here” quorks. The calls came from a half mile to the south of the bait, then from the west side. Then they ceased as the pair left. Eight minutes later, Number 837 was back and snacking lightly. She obviously could feed at this bait despite the territorial defense of the adults. She just couldn’t feed whenever she wanted to. Presumably, this situation could change if the adults started to use this as their main food supply. So far, they did not seem at all interested in feeding. I was surprised that they went to so much trouble to defend a food site at which they were not feeding, though I thought it might be on their checklist as a possible future feeding site.
Would Number 837 not recruit at all, given that she was able to feed successfully? Our bird’s failure to recruit might not seem very exciting, but we were not just raven-watching. We were also hypothesis-hunting. It might turn out, given everything about this bird and this situation, that lack of recruitment would be the most exciting result
of all.
At 1:12 P.M., another unanticipated event made us rethink the original hypothesis. Two ravens flew over, then quickly descended to the woods nearby. One of them called loudly, but I knew it could not be one of the pair, because these two did not make any territorial quorks. Instead, for the next twenty minutes I heard a completely new spectrum of sounds, a steady singsong of slow rasping quorks intermingled with rolling, gurgling calls. There were also many series of rapid, percussion-like knocking calls, each series punctuated with the pop of a bill-snap at the end.
These birds stayed in the woods mostly out of my sight. Once, I managed to glimpse Number 837, conspicuous because of her red wing tags and her radio signal. She was near a second bird, and they were both making gurgling, friendly calls.
One of the new unmarked birds eventually landed on a tree above the meat pile and leaned way below its feet to peer down. It nervously doodled and pecked at branches. Then it again peered down at the meat and made long series of rasping quorks that sounded to me just like those our tame birds made when they had an unfamiliar scary animal carcass in their aviary. This bird was obviously afraid of the meat pile.
The new ravens were hyper-alert. They seemed ready to fly off at the slightest disturbance. In my blind, I could sense this, and I rolled over ever so cautiously to get a better look. The fabric of my pants made a tiny rustle—that was enough. Off they went with heavily pounding, fast wing-beats—swish, swish, swish. With all the ravens gone, blue jays, totally nonchalant by comparison, flew down to the food. They treated the bait as if it were—well, just dead meat! When they came down, they instantly hopped right onto the meat and started feeding. Just for a test, I loudly whistled “Oh, Suzanna” and athletically jumped around in the blind. They took no notice. I only managed to scare them by coming out of my blind. When I went back in, they returned in a few seconds.
At 2:05 P.M., all was quiet again. I had regained radio contact with 837, who stayed nearby in the woods for about an hour before coming by to feed. The wind had shifted from west to north now, picking up speed all the time. The woods sounded like a giant surf, ebbing and flowing. The temperature kept dropping, and I was soon shaking like a leaf in the wind.
As the afternoon light was fading, I dashed out of the blind, running the half mile to my truck through deep snow to get warmed up again. It had been a long day. I was thankful it wasn’t 20 degrees Fahrenheit, as it could have been. I took another radio bearing on the bird—she was down by the lake in the grove of pines, where she had been for the last two nights. She was sleeping alone again.
Then I heard quorks above me. Looking up, I saw a fantastic sight—a group of forty or so ravens, gamboling along, flying in pairs, singles, diving, chasing, but generally moving toward the roost that I knew John was observing from his tall spruce. Where did this group come from? Where were they going? Was it a coincidence that they just happened to come directly over the bait?
Down the road three to four miles where John had his truck parked, I saw his silhouette against the rapidly fading western sky. He yelled as he saw me jogging over to his tree, “Did the crowd feed at the bait?” Apparently, he’d seen them.
“No. They kept right on. Did they drop into the roost here?”
“No luck. They flew in a giant circle, covering miles of territory, and then they headed back out again in your direction.”
High circling at an old roost site in the evening is something we had noted before on many occasions. It is usually a prelude to the whole roost taking off to a new feeding site. We guessed circling happened when one or several of the birds in the crowd knew of a new food location. Maybe the display brings all the neighboring birds together.
Round and round the growing mob flew, perhaps two or three thousand feet up, as ravens from all around joined, swelling the ranks of the soaring group. Finally, the whole group took off, presumably to settle into a new roost near another food bonanza. I previously had seen the swirling groups of ravens at a roost, only to find the roost empty the next day. I sensed that they represented some kind of mysterious yet unknown social communication.
It is not just the “kettle” flights themselves that fascinate me, but the sensual electricity of the whole event. Garrett Conover, a Maine wilderness guide, once wrote to me: “We camped one night in the lee of the cliffs at Mount Kineo [on an island in Moosehead Lake, in Maine]. Just at dusk hundreds and hundreds of ravens began to arrive and cavort in the calm air in the lee of the cliffs. As dark fell they kept flying, though many landed on the face of the cliff. We lay on our backs looking up through layers and layers of wheeling ravens…Later a full moon rose and the birds stayed vocal all night long, quieting only when the moon set just before dawn. At first light we left the warmth of the tent, damped the stove down, and rushed out to see what the ravens were up to. All were gone without a trace or a call. It was like a splendid dream.”
Similarly, I once received a letter from Virginia Cotterman, who lives in the Mojave Desert in California. She had observed 1,000 to 1,500 ravens roosting for thirty-six consecutive nights in the desert near her home. One night for the first time, they were vocal long after dark, almost to midnight. Why that night? They left before dawn, as usual, but they never returned in the evening.
I wondered if what John and I were seeing here in Maine was one of these coordinated departures. John had seen thirty to forty ravens circling for an hour before heading in the direction of the bait. Number 837 avoided this soaring crowd. She fed and slept by herself without joining a roost. She could not have missed the huge crowd flying over. Had she chosen not to join it because she had her own, almost private large food bonanza? Is the policy of raven vagrants that if you are hungry and have nothing, you join a crowd and follow, and if you are sitting on a good pile of food that you have reasonable access to, then you stay by yourself?
When the chilly dawn came on December 20, I was off as usual, trotting down the trail under a starry sky. After the fifteen-minute drive, I crossed the field to my blind. Thick black clouds were rushing overhead from the west, but a few patches of sky revealed stars. A shadowy figure ran ahead of me over the snow. It stopped and looked back—a fox on its last rounds. I stopped as well, then we both went on, the fox to a den, me into my little hollow surrounded by evergreen twigs.
I had time to pause before entering this morning, because I had arrived early. It was absolutely quiet. No wind. I hoped to hear the ravens come from a distance. In my previous experience, when ravens arrive in the dark on the first few dawns to a new food bonanza, they sound off with all sorts of amazing calls from their repertoire. It’s an unforgettable experience to see and hear what seems like an uninhibited display of life and joy. But the stillness was left unbroken. As the sky got lighter, I retreated into my blind.
It was 6:45 A.M., the anticipated magic arrival time. Nothing. 6:50…6:55…7:00. Still nothing. It was fully light now, and I was sure the crowd would not appear all day. The birds’ decision about where to go had been made last night, or at the latest before daylight. It probably had been just a coincidence that the swirling crowd had flown in the direction of this bait—they had been flying to some other destination, possibly ten to twenty miles farther on. I knew all of this, and it was barely light. I still had a whole day ahead of me of sitting immobile in my blind.
I lay down on my deerskin in the semidarkness and scratched notes on folded sheets of paper, kept dry in my back pocket. After twenty minutes, the cold was already creeping in, due to my inactivity. When the body suffers in this cold, the mind does not work very well either. There was nothing exciting to look forward to. There were no birds to be seen, and there was no assurance that any would come. I had no idea—not the foggiest notion, when I might be the beneficiary of a pleasurable reward. It could be days from now, or weeks, or months.
Indeed, the territorial pair were unpredictable in their arrivals. They came at 7:10 A.M. that day, then stayed in the vicinity much longer than previously. I heard their aggr
essive interactions with other ravens until about 9:00 A.M. Presumably, these were not only against Number 837, but also yesterday’s newcomers. Number 837 did not get to feed until much later than usual. Her descent near 8:00 was her only opportunity to feed. The two other vagrants of yesterday edged close to the food only when she was feeding there. She paid no attention to them, again confirming that she was not defending her find of this food bonanza. They needed each other’s company as a shield from the adults who might come at any second.
At 1:20 P.M., a bird I could not see in the woods made sounds that could pass for someone hitting a metal stake into the ground with a metal hammer. The metallic thud was repeated several times, then the raven came out of the woods to perch near the bait. Other sounds now: a soft growl-pop-grr sequence, repeated at intervals, followed by a rasping series—rraap, rraap—to be followed by several soft hooting calls. Then the caller left. What was that all about? What was the bird signaling? And to whom? Why so many different calls in rapid succession?
A little while later, I heard the more familiar rapid series of percussion sounds, each followed by a pop. Also, there were regular repeated quorks. What strange goings-on I was observing! I felt a certain snugness in my blind. In the woods, a human is almost always seen by the other creatures first. Here, it was the opposite. They could hardly know I existed. Repeatedly, ravens had landed almost on the blind or beside it. They could not see into it, but I could see out.
I liked being invisible among them. What’s more, I possessed an almost supernatural power—I could identify some as individuals, and with the radios on, I could find out where they slept and thus find their roosts without actually seeing them at all. Unfortunately, ravens do not form one tight group that can be followed within a certain area. The population wanders over many thousands of square miles. After a bird is marked, it will not stay. Once a bird finishes feeding at a bonanza, it may be in another state the next day. I might complain about this habit of ravens, but to some extent, it is why I study them. What is easy is exhausted quickly.