Mind of the Raven: Investigations and Adventures With Wolf-Birds

by Bernd Heinrich

  I needed more reliable access to the nest in the coming days and weeks, and since visitors were not available every day, I had to improvise. For the most part, I learned that I could hold them off by carrying something bulky in my hand. A paper bag would do. They never took my advances personally. Afterward, without holding a bulky object, I often sat for hours within five feet of them and the nest, and they both ignored me—provided I did not move toward it. My slightest movement towards the nest set them off in vehement threats that would make my heart pound, because I knew I’d get hammered. I expected fully that Houdi would fly in my face and peck hard.

  Five eggs were laid, about twenty-five hours apart from each other. I marked each one with a small piece of numbered duct tape to record the sequence in the clutch.

  Matings occurred almost precisely at the same time and in the same way at dawn every morning, and stopped on the morning that the fifth egg was laid. It was always the same ritual. Each mating was initiated when the female hopped off the nest to stretch on her first morning break. He sidled up to her and did his macho display. She responded with her knocking display. He then drooped his wings and vibrated his tail. She then went down, crouching in the same display, and he hopped on to mate.

  Ravens have always been assumed to be monogamous and keep their mates for life. But as with almost everything about them, it depends strictly on circumstances. There is ample documentation in the literature showing that if one member of the pair gets killed, a replacement may appear within a day. Recently John Marzluff, who has continued working with corvids in the western United States, documented extra-pair copulations in ravens inhabiting the open country in Idaho. He saw four males other than the mate (who was wing-tagged) copulate with a female, and he saw extra-pair copulations at the two nests under observations. John said “the sneakers wait until the exact moment when the territorial males leaves, which is very infrequently. They streamed in as soon as the male left. They would do this only at egg-laying time—exactly when it would result in fertilization.” Interestingly, these copulations differed from the ones I saw of the legitimate pairs. These extra-pair copulations occurred at any time, not just at dawn, and they occurred when the female was sitting and remained sitting on the nest, not off it. It seems as though the secondary males know what is going on, not only with regard to the precise reproductive status of a female and/or her nest other than theirs, as well as her mate’s mate-guarding behavior.

  The eggs were a little more pear-shaped than a hen’s egg, and smaller than a “Grade A Large.” The first one laid, which was infertile, was so thickly blotched with grayish black that the greenish-blue background color was almost totally obscured, especially at the thick end. Numbers two and three had distinct blotches, and the fourth one had even fewer. The fifth egg was the most distinctly colored. It was light blue-green with only tiny pinpoints of dark markings, mostly at the narrow end.

  I removed each egg after it was laid, intending to return them all after egg-laying ceased, to see if the birds would continue to lay as some birds do, until they have a full nest. They stopped after laying five eggs, even though never finding more than two in the nest at once. When I returned all the four eggs I had previously removed, Houdi hopped onto the nest with five eggs, even though a minute before she’d been sitting on just one, without exhibiting a flicker of surprise. From that point on, after all the eggs were laid, only she incubated. When she did leave the nest temporarily, she hopped about frantically and then went right back on. She rarely fed on her own. Instead, Fuzz brought almost all her food, feeding her just outside the nest or in it. He nudged her bill if she hesitated to take his offerings. Sometimes, she begged like a nestling.

  The third and fourth eggs hatched on April 4, twenty-one days from laying. Two chicks had hatched two days earlier, which suggested that the eggs I had removed from the nest for three and four days had already been partially incubated on March 16 when they were returned to the nest.

  Fuzz and Houdi’s behavior toward me changed markedly after the young began to hatch; their aggression increased to new levels. As the pair became ever more defensive, I dreaded retrieving the young to weigh them every two days. At birth, the chicks weighed 25 grams each. By April 13, the four young each weighed 350 to 360 grams. Their eyes started to open, and although they were still naked, black stubble of new feathers was visible under the skin. In fourteen days, they increased their body weight by twenty-four times, to 600 grams. They became feathered out by thirty-two days, but did not leave the nest until the age of forty-eight days.

  The just-hatched young were vocal from their day of birth, but they did not reach up their heads to gape and make their high-pitched, hoarse, begging cries unless the parents perching on the nest edge made a soft little grr sound to them. At two weeks, they begged in response to almost any disturbance, no longer requiring the parental grr calls to get them to gape.

  Fuzz was a devoted father. He and Houdi fed meat to their young directly after tearing it from animal carcasses and storing it temporarily in their throats. When they spat the meat up, I often saw saliva coating it. I wondered if the saliva contained digestive enzymes. Both parents ate only after the young would eat no more. Mice were a preferred baby food. The ravens would tear them into small bits, carefully draping the entrails over a nearby limb to discard them or eat them themselves. When Houdi sat on the young and Fuzz came with a throat full of meat, he first gave her some of it as she stood up, then he fed the rest to the young himself. When I gave them several mice at once, they grabbed as many as I had and cached them, retrieving and tearing them up afterward.

  The foods they ate were not necessarily the same as those they fed the young. The young got only meat. When available, the pair ate or cached berries and butter, but gave neither of these foods to the young. The parents ate the biggest, roughest pieces of meat with bones and skin after giving the young the juiciest, choicest parts.

  Throughout all of incubation and until the young were feathered, when she stopped brooding them, Houdi never once bathed. Her wings, breast, tail, and especially her feet became badly soiled. Fuzz bathed in water when available and in snow. She only preened.

  The time had finally come when I felt secure enough to open the aviary, because I did not believe they would leave their young. On April 20, I opened the door. They were not in a rush to leave, but Fuzz eventually did fly out. The neighboring pair of resident ravens that nested a mile down the road were there, as if on cue, to meet him. The neighboring male instantly lit into Fuzz. A huge chase followed, and that was the last I ever saw of Fuzz.

  Houdi hid in the nest shed, silent while her mate was being attacked outside. It was only hours later that she ventured back down onto the floor of the aviary to feed, and the next day she went to the calf I had provided outside the aviary.

  For the most part, she remained silent. Eberhard Gwinner, who studied ravens in Germany in the 1950s and 1960s, had reported that a raven missing its mate called the equivalent of its name by using a vocalization only the missing bird had used before. Not Houdi. Instead, her most common call was her own name—the knocking that said “Notice! It’s me. I’m female.” Only one time, at around 10:30 the next morning, did she finally go through a repertoire of other calls: rasping honks, undulating, territorial quorks, “dog whines,” and rap-rap-raps. Three times I saw ravens fly by at great height. She became silent and perched immobile in a pine tree. On another occasion, when one raven came close, she flew into the aviary and hid next to the nest in the covered shed, cautiously peeking out. She did not venture out until the bird had left.

  Near 6:00 the next morning, she did the female knocking calls for minutes at a time, and no other calls. To me, these calls made sense if she thought Fuzz was searching for her. However, they attracted not him, but another wild male, who was not unwelcome. Houdi stayed in the trees outside the aviary, next to this new male, who I presume was the same neighbor who had chased her mate off. The male did his macho displays of bo
wing, blinking, and groaning to her, and she reciprocated by continuing her knocking display. It looked like a typical boy-meets-girl situation.

  After a half hour, the male left and Houdi resumed tearing meat from the calf I had provided in the nearby woods. She fed the chicks as though nothing had happened. I sat near the calf and she came right next to me, exhibiting no fear or apprehension. What a joy to see her flying freely over the woods where the poplars were all tasseled out, the willows starting to bloom, and the first warblers, the solitary vireo, and the winter wren were singing! She brought huge mouthfuls of meat, one after another, to the seemingly insatiable young in her nest in the aviary. Often, she dropped a big load of meat near the nest, then made as many as four smaller trips to feed the young from that one load.

  Once a pair of ravens suddenly arrived, both making long, nasal honks. Houdi was at the carcass tearing off meat. She instantly aborted her work and silently, without a load of meat, retreated into the aviary to hide in the nest shed. She didn’t make a peep and looked totally intimidated. Meanwhile, the pair helped themselves to “her” calf. Undoubtedly, this never would have happened if she had a mate. A mate in this situation would have been in an unstoppable fury. I felt sorry for her, and handed her a hard-boiled egg from my bedroom window that opens directly to the nest shed. She immediately fed it to her young.

  Almost twenty minutes after the pair had left, she still remained silent and in hiding. Sometimes, she stood stock-still, head straining down horizontally to peek under the roof overhang. Was she wondering, “Are they still there?” Did she know that this time, her paramour’s mate had come along and that the female bird would not be so tolerant toward her as he was?

  To encourage her, to let her know the coast was clear, I went to the carcass and called. She would know that no wild raven would be near with me there, and indeed, she instantly flew out to me. She wasn’t there more than a few minutes before a lone raven appeared. She stayed put, made a variety of calls, then she flew after it! The two settled next to each other. I presumed it was the male again, alone this time. He displayed his macho poses to her, and she acted coy. The party didn’t last long, though, as a second raven appeared within several minutes. Undoubtedly the first bird’s mate, who chased after Houdi, but seeing me, then swerved and flew off directly to the Swamp Road nest where I had suspected the pair was from, as they had often fed near my house in winter.

  It was 8:00 A.M., and I had to leave just as things were getting to be fun. I could not come back to resume watching until 3:00 P.M., when I saw the neighboring pair arrive again. Only one of the pair gave Houdi chase. The chaser had a fluffed-out fuzzy head, and Houdi depressed her feathers, making herself look thin. The duo went out of sight. There was a long silence. I became worried. Thirty-five minutes later, I heard raven calls and saw two flying over. One came down. It was Houdi. She resumed feeding at the carcass and I felt greatly relieved, being confident now that together we’d raise these young, despite the pesky female neighbor.

  After this, the male visited often. Always he and Houdi displayed to each other. He flew after or toward her at times, and sometimes she flew over to meet him. Never once was there any aggression between them.

  On May 1, I was almost startled to hear her start the day with a “shout” of vocalizations; fifteen minutes or more of knocking calls, kek-kek-kek calls (no predator near!), dog whines, long, undulating, territorial quorks, upward-inflected, rasping calls, and many others. She was animated as never before, looking in all directions, flying over the fields and forest, then flying back to land on the trees by the aviary and her nest. She was full of force and power, not shy and tentative anymore. Something was up.

  The next morning, in contrast, she made no calls at all! It was very unusual, yet I didn’t anticipate anything. Too bad, as it turned out.

  I left in the afternoon on my long-planned trip to Maine, first leaving her a calf. When I returned on May 5, Houdi was gone! The young were very hungry. A friend told me later that he had seen Houdi in the late afternoon on May 3, flying along the Hinesburg Road (close to where the other pair have their nest). She had been identified by the two missing wing feathers on her right wing. I never saw her again, and I was left with her four young.

  My trip to Maine had been to check on Goliath and Whitefeather. After I had provided them nest material on March 6, they had completed their nest in just two days! On April 23, when their young were ten days old, I watched them as Whitefeather made squeaking noises to Goliath, and they held each other’s bills as in a long kiss. For long periods, they sat close enough together to be almost touching. They paid so much attention to each other that I wondered if they had forgotten their young. I tried to remain hidden and watched from a shed through a one-way mirror. In the two hours and fifteen minutes that I watched, he brooded the young for one thirty-seven-minute session, she for four sessions lasting five, three, five, and fourteen minutes. He fed the young three times, each time afterward eating their feces. She fed them only once, and she ate the mice I had brought. He was totally quiet the whole time. She was very noisy, making three long sessions of knocking. At one point, she made a long series of rasping high honks, rapid nasal honks, caulk-caulk-caulks, rap-rap-raps, undulating territorial quorks, and ripping, rasping quorks. All these calls were apparently directed to distant neighbors to the north and southeast, because I could hear the ravens at three distant nests in those directions respond with their own calls.

  As described in more detail elsewhere (Chapter 12), I eventually pawned off the four abandoned Fuzz-Houdi offspring on Goliath and Whitefeather. Then I opened their aviary as well. I expected things to proceed differently. First of all, Whitefeather had been captured from the wild. She was in home territory. She had seen the hills, the forest, and the lay of the land from the air. She might still know the neighbors. She would not get lost or disoriented if chased by them. Goliath had been free in these forests as well for a time after he had fledged. It was with confidence that I tore out one side of the aviary, so that the birds would have easy and direct flight access to their nest, filled now with six young rather than just two.

  Within minutes, both adults were out. After tarrying briefly in the large maple trees next to the aviary, they were, like the Vermont pair, also immediately met by a neighboring pair of ravens that magically appeared out of nowhere. Here there were no chases. Instead, all four birds perched together, making mutual dominance displays, but I could not determine the outcome, because all four soon left together as a group, vocalizing energetically. Their voices soon were lost in the distance. Through my binoculars, I saw them disappear, tiny black specks high in the sky to the north. All morning they were gone. I heard not a sound. All afternoon they were gone as well. I fed the young myself, thinking I now had created six orphans. I fretted all night, but at dawn the next day I heard two ravens calling by the aviary. Goliath and Whitefeather were back! Their absence the first day was to be their only one for the next two months.

  Some of my greatest contentment that summer came from sitting on a log next to the aviary and watching both birds fly in and out, caring for their young. Goliath readily came up to me, taking tidbits from my hand. Whitefeather, being wild-born, never came that close, but she didn’t act alarmed, and came within twenty feet of me. Unlike Fuzz and Houdi, they at no time scolded me, even when I climbed right up to the nest to look in at their young.

  When the young fledged, they behaved like young ravens do normally. At first they hung out near the nest, tearing and picking apart everything within reach. Gradually, they expanded their excursions, following one or the other or both parents, sometimes going alone. By July, they were taking independent excursions, and soon after that I did not see them anymore.

  Several days after the young left, Goliath and Whitefeather left as well, but following a month’s vacation from the heavy duties of child rearing, they were back again. As before, they raucously sounded off with a barrage of calls every dawn. I expected them t
o adopt this hill as their territory and to settle here for good.

  Goliath and Whitefeather, living free around my cabin, had given me a chance to view ravens’ interactions with neighbors at close range, and I could routinely watch them. One day after Whitefeather flew from the aviary, I left a chunk of meat on the path in the woods about two hundred yards north of the aviary, where neither she nor her mate immediately found it. I saw a pair of ravens flying at great altitude, and these newcomers tumbled down out of the sky toward the meat, landing in a red maple tree, where they called several times. Whitefeather left her perch by the aviary in a big hurry and went directly toward them. I then saw all three within a few feet of each other, at least one bird doing macho poses and Whitefeather knocking to them. Seeing me, the two newcomers left, and she returned to the aviary. A few days later, Goliath and Whitefeather were flying with another raven, and she took the lead in what seemed to be escorting it away; she flew closely behind the other raven, who was yelling a lot. Goliath lagged behind. Again and again, the stranger flew back to the clearing by the cabin, and eventually a second one joined it.

  It never failed when a raven called from the distance that Goliath and Whitefeather instantly tensed up and responded, trying to “outshout” strangers with territorial advertisement calls. One spring morning, with Goliath beside me, I again heard raven calls in the nearby forest. Goliath, who usually went ballistic at the sound of strangers, acted unconcerned this time. Strange, I thought, so I went into the pines to check, and sure enough, it was Whitefeather. Later, as both were at the aviary, I saw a raven flying at a distance of perhaps a mile. Both were after it immediately. A few hours later, I was up in a spruce and saw a raven flying silently in the valley heading toward Lake Webb. Whitefeather and Goliath erupted in rasping caws, and Whitefeather took off after it, and the two flew together. Not knowing otherwise, one might well have thought Whitefeather and the stranger were a mated pair. The “pair” flew together for miles—to Gammon Ridge, Mount Blue, and then down to Alder Stream. Goliath stayed near me and the nest and made undulating territorial quorks. After five minutes, Whitefeather came back alone, and both she and Goliath gave the undulating territorial quorks. An hour or so later, a pair flew over the aviary. First Whitefeather took off after them, then Goliath. This time, there was an aggressive chase. I heard staccato chase calls and the begging of the chased birds. This time, it was not play. They were gone more than five minutes, Goliath returning first. Both did deep, rasping caws and rap-rap-rap calls.