Mind of the Raven: Investigations and Adventures With Wolf-Birds
Page 14
In January 1995, I let Fuzz and Houdi remain in the complex in Vermont and took Goliath and Lefty to my aviary complex in Maine. The pair were housed for the most part in their own side aviary, separated from the main aviary that was then holding a crowd of wild-captured juveniles. On April 26, I let the pair into the main aviary with the crowd. Would Goliath be beaten up when entering their domain? Not at all! Goliath seemed eager to join them, then immediately attacked all the top males, especially G67, the most dominant one there. Within a day, G67 and all others yielded to Goliath. He chased them and did the macho display until all stopped fighting back. He had concentrated his attention on those who resisted. He seldom approached females, with the exception of one bird with a white feather on her left wing. He initially greeted her with the same macho display he used when approaching males. Being a female, she responded not with fighting, fleeing, or submissive gestures, but with her knocking display that says, “I’m a powerful female.” He then stepped aside. I could thus sometimes tell the sexes apart by behavior, and maybe that is how they do it as well.
Afterward, I tried to chase Goliath and Lefty back into their own private side aviary. They knew the door, because they had once been free to use the whole aviary, but they both seemed determined to stay in the big aviary. Goliath looked at me pointedly, then pecked branches angrily and erected his macho-pose ears. He had never reacted to me that way before, and I had always shooed him back easily. Lefty, who also refused to go back, found a hole in the wire and escaped the aviary. She sat above in a birch tree for a while, made some kek-kek calls, and flew off down the valley toward Alder Stream, While all this was going on, “Whitefeather” flew into Goliath’s aviary. Once there, she immediately made long, undulating, territorial calls I’d never heard from her before, and in his aviary the calls were especially surprising. Normally, these calls don’t attract other birds, but Goliath reacted instantly by flying to her, back into his aviary. I expected him to attack the interloper. Instead, he sidled up to her as she gave a bowing, fuzzy head display and repeated a long series of the three repetitive knocking female-indicating calls. She meekly stepped away. He then did a little macho display, but without much bluster. Then all was calm. No fight. She later did long series of the quick repetitive knocks. I felt a match had been made, and closed the door to “their” aviary. There was no point in me trying to get Goliath and Lefty together again. Fate had decided otherwise, and I was curious to see what would happen next.
When Lefty came back from her visit to the wild ravens feeding at a calf carcass a mile away, she paid no attention at all to Goliath. She perched above that part of the aviary housing the strangers, totally ignoring the side aviary with Goliath and Whitefeather. So much for what I presumed had been a love match. If Goliath and Lefty previously had a relationship, it was clearly only one of convenience.
It was time for me to release all the wild birds other than Goliath and Whitefeather. I opened the door of the big complex, leaving a raccoon carcass as bait just outside the door. Some of the birds stepped out to feed, but they did not fly away. Instead, they returned to the aviary after their meal. In the evening, others tried repeatedly to get back inside, walking paths in the snow along the wire. It took two days before they stayed out.
Weeks later, Goliath, my tame, hand-reared bird, and Whitefeather, the wild raven, were still paired like a loving couple. They perched next to each other, preened each other, and cooed softly to each other. Lefty had departed for good. I wondered if the Goliath-Whitefeather pairing was also one of convenience and might easily be disrupted when an opportunity arose. There was only one way to find out: provide that opportunity. On July 22, I brought Goliath and Whitefeather to Vermont, to release them into the home aviary with the Fuzz and Houdi pair. I would there keep the four together for four months.
I released Goliath first. Hopping out of his crate into his home of months earlier, he seemed fully relaxed. He shook himself. Fuzz made the rap-rap-rap calls, on high alert. He had been subordinate to Goliath before. In Goliath’s absence, he had not been challenged. Now he proceeded to make a macho display, sidling up to Goliath. Houdi stayed up out of the way in the sleeping shed, giving some knocking calls. Fuzz stood tall, bill-snapped, flashed the white nictitating membranes of his eyes, and strutted. Goliath did not respond. Fuzz then attacked, and Goliath assumed the “crouching pineapple” submissive display, which I had never seen him do before. The contest was over, just like that.
A raven pair, alert to a neighbor’s calls.
Goliath, previously dominant over Fuzz, was now submissive to him. Established within the first few minutes of the encounter, this relationship was maintained from then on. Their tense social interaction deescalated in the next forty-five minutes, but the result was clear. Houdi had stayed totally out of the strictly male-male encounter. Then I released Whitefeather. Would she be challenged and beaten by the resident female, just as Goliath has been beaten by the resident male? That’s what I would have bet, especially since Whitefeather, a wild bird, would now be in a strange new place without the home court advantage.
As Whitefeather flew out of her crate onto a perch, Goliath flew to her and macho displayed. She started knocking. Very soon they had bill-to-bill contact and briefly preened each other. Fuzz made a new ringing-rasping call I had never heard him give before. It was long and oft-repeated. Houdi, hearing Whitefeather’s knocking, responded for her own part with paroxysms of knocking. Neither female engaged in body contact like the males. For about ten minutes, both females knocked almost continuously, then their vocal duel tapered off. Whitefeather had the last word, and Houdi became quiet.
After that day, Goliath continued to be subservient to Fuzz, and Houdi, in turn, always yielded to Whitefeather. Houdi, who before had routinely engaged in knocking displays every day, no longer knocked at all. Not once. Indeed, the noisy Whitefeather seemed to inhibit all of her vocalizations. In turn, the previously vociferous Goliath became totally silent as well, and he always yielded physically to the now-expressive Fuzz whenever there was food.
Although the dominance had been reversed, the pairing or preening bonds had not. The females continued to preen only their males. Whitefeather, the dominant female, stayed with Goliath, her now subordinate male. Similarly, Fuzz, the most dominant male, remained true in his preening to Houdi, the now-silent subordinate female. Each day, the members of the respective pairs sat long hours side by side with each other.
Curiously, Goliath, who until then had been the only one to greet me routinely by doing the crouching, tail-quivering, entreating display, no longer gave me this display. Conversely, Fuzz now greeted me with the standard male macho display used to impress potential mates and male rivals.
The dominance hierarchy amongst the birds was most readily seen at contested resources, principally perches, food, and the bathing bowl. When it was time for a bath (in the large wheelbarrow), the most dominant bathed first and the most subordinate last. But there were constant attempts at line-crashing, which were met with much shoving.
July 22, 1995, was a scorching hot day with temperatures near 90 degrees Fahrenheit. After I poured the water into the tub, Fuzz came down and walked right in. He ducked and splashed until all of his feathers were comically matted into tufts, streaming water. Bath done, he flew up to the roost to preen, and only then did Goliath cautiously approach the water. Fuzz would normally preen for a half hour, but seeing Goliath approach the water to enjoy a bath, he interrupted his preening and flew back down, still totally soaked, to take another leisurely bath. When finished, he went back up to his perch to resume his preening. Having barely started, he again stopped to chase Goliath, who had attempted to reach the water once more. This sequence was repeated eight separate times before Fuzz finally allowed Goliath to bathe, or he allowed himself to preen. I could see no practical point to his costly exertions to exclude Goliath from a bath, except maybe to show that he could do it. There are people like that, but I was surprised to see rav
ens being so unreasonable.
When Goliath was finally allowed to bathe, he was continually interrupted by Whitefeather. She didn’t actually get into the tub with him, but came near, obviously intending to join him in the two-foot-diameter wheelbarrow bowl that was surely big enough for two. Goliath invariably interrupted his bath, however, just to chase his partner off. Long-paired partners become progressively more tolerant of each other, bathing and feeding together.
Houdi tried to be next. She was immediately chased off by Whitefeather even after Whitefeather was done bathing. During the time Whitefeather was trying to prevent Houdi from bathing, she kept giving her female power-call, the knocking. Houdi, in trying to sneak in to take a bath, kept looking all around at the others, as if to make sure they were preoccupied before she dared a try. They always saw her. Eventually, she gave up.
After four months I separated one pair from the other, not only to terminate the fidelity test, but also to permit each pair to eventually build a nest and raise young, since both pairs could not be expected to nest in the same aviary. I kept Fuzz and Houdi in their home aviary in Vermont, and brought Goliath and Whitefeather back to their aviary at my cabin and study site in Maine, where they had originally met.
On November 21, 1995, the day I separated the pairs, Houdi underwent a remarkable change. She regained her voice—and with a vengeance. She did the knocking calls continuously for hours on end. When the pairs had been together, Fuzz had bitten off the end of Goliath’s tongue. I had thought that possibly Goliath’s silence had been due to that injury. It wasn’t. As soon as he was away from Fuzz, he regained the full range of his voice with no change at all in his calls that I could tell, tongue or no tongue. He also resumed his macho displays.
Despite their separation, the stories of Fuzz and Houdi, and Goliath and Whitefeather, later became closely intertwined. By Christmas, Fuzz and Houdi were still the epitome of a loving couple, preening each other almost every minute of the day. He preened her about twice as often as she him. To solicit preening, she pursued him, perched right next to him, and bent her head over as he folded over one feather after another with his bill After a while, he reached under her throat, and she arched her head up over her back for him to preen her throat, feather by feather. I’ve never seen a single parasite on either one, although they did remove rare specks of dirt from the feathers. Fuzz did not seem to solicit preening from Houdi. Instead, he did many of his macho displays accompanied by 00-00 calls, while seeming to push her. Houdi responded with her knocking display, and occasionally placed her foot on his back. He sometimes sidled up to her, reached out with his nearest foot, and grasped hers firmly for many seconds at a time. I could not tell what the foot-grasping meant, except that sometimes it seemed as if it might be used as a mild restraint.
Houdi was playful. She slid and rolled down a two-foot-high mound of snow on her back. At first, the snow-sliding seemed almost like an afterthought as she simply allowed herself to topple over while Fuzz was preening her on top of the mound. After that, she did it several more times on her own.
On January 28, Houdi brought two sticks into the shed where I hoped they would nest. Fuzz took an immediate interest and followed her closely. When she brought the third stick up into the shed, he picked one up, too, and followed her to the spot where she had deposited hers. Was she telling him something?
In the next two weeks, Fuzz alone carried sticks. He not only carried them to the designated spot for the nest, he also held them fast with his bill and rapidly vibrated his bill with the stick in it. Such vibrations normally function to anchor sticks to each other and to the nest substrate, but their nest-building seemed more like play. At first, as many sticks fell out as were carried up. Houdi accompanied Fuzz and watched him work; she carried no sticks herself. They were almost three years old. Were they too young to seriously build a nest? Perhaps all the neural connections necessary for nesting behavior had not yet been made or activated.
Almost a month later, on February 22, the nest still consisted only of a loose bundle of about ten sticks. Were they missing something? I put an old sheepskin with long tufts of wool into the aviary. Both looked at this material intently. He then grabbed a stick lying nearby and took it to the nest. She took a piece of sheep wool, shredded it, then carried it to the nest as well. Now he got busy! Again, as if he’d suddenly caught on from her cue, he began carrying more and more sticks in, even two at a time. In eighteen minutes, he had carried in eight sticks and she had brought up three loads of fur. Both had also played with more sticks and fur. When I gave them dead grass, she picked it up and carried it in one large load. After that one billful, she picked up a huge ash stick, one that was an inch thick and two and a half feet long. She debarked the stick, held it in one foot, and let it dangle below her before eventually carrying it to the nest. Then she was done. She sat on the nest edge, preened, and did many knocking calls. Did her actions tell him to get busy? It seemed so, because he started carrying in as many as three sticks at a time, although still ignoring the wool and grass.
Only one day later, Fuzz had finished the stick “basket.” I gave them piles of inner bark from a dead poplar. This they both carried into the nest, accompanying each other. Both were now almost equally engaged carrying load after load of bark fibers and wool. By the next day, Houdi was making three trips with nest lining to the nest to his one. He still picked up sticks, dropped them, picked them up again, as though forgetting what they were for. It was only the lining that the nest then needed. The next day, February 27, the nest seemed ready. It had a beautiful, deep, soft lining. The whole structure measured thirty inches across and twenty inches tall, and the nest cup was twelve inches across and six inches deep. I expected eggs any day.
On March 8, I saw Houdi sit down in the empty nest, turning around in it several times, but sitting quietly most of the time without moving. After one of her nest-sitting sessions, from 8:19 to 8:35 A.M., I checked the nest, but it was empty. Fuzz still accompanied her every move, perching next to her even when she was in the nest. At 8:54, she again went into the nest to sit. After she sat for six minutes, she hopped out and he took his turn for four minutes. At 9:27 A.M., he hopped out and she sat quietly in the nest again for seven minutes, while he did his macho displays. He then took another turn for four minutes, while she did her knocking displays. She took two more turns of nest-sitting in the still-empty nest for nine minutes and three minutes, respectively. Several times, he laboriously picked hair off a moose hide I’d provided them, then spat it out and discarded it. Meanwhile, several times when she hopped off the nest onto the ground, he walked up to her to hold her foot, as she lay down on her side beside him. Were these preliminaries to sex?
The next morning as a wild raven flew over, Fuzz went into paroxysms of deep angry quorking. Later, he perched in uncharacteristic silence with a partially fuzzy head. At frequent intervals, his whole body shook and vibrated for a few seconds at a time. I had never seen him do that before, and would never see it again. He was not shivering from cold, because it was a warm day. I sensed a great excitement in him. Had he taken a cue, from the finished nest, that it was now time to mate?
Two mornings later, on March 10, 1996, I found the first egg in the nest. Houdi sat on it most of the day. Fuzz perched stolidly nearby for hours, making oo-oo calls, bill-snaps, macho displays, and undulating territorial calls.
Already at dawn the next morning, he began making long, deep, rasping, territorial quorks telling all neighbors to keep away. She was on the nest. He maintained high alert, looking around in all directions. At 6:30 A.M., she hopped out of the nest, stretched her right wing, and hopped over to him on his perch. He greeted her with his macho bill-clicking display, and she responded with her knocking display. He then waddled sideways to her along the perch and reached out with his right foot to grasp her left. She skooched down, arching her back and rotating her tail, and he hopped onto her back. He lost his balance, and she then flew to the ground. He followed. She
crouched again, with rapid tail vibrations, and he responded with a similar crouch and tail vibration with his wings held widely to the side and his bill up at an angle of about forty degrees. He did this for only a second or two, then hopped onto her back again, perching directly on her, while maneuvering backward to make cloacal contact. In two to three seconds, it was all over, and she walked over to the calf carcass to feed. He flew back up to his perch. I quickly took the opportunity to check the nest. No second egg yet.
At 7:10 A.M., she hopped out of the nest and he hopped on, remaining there for forty-three minutes before she came back and perched next to him at the edge of the nest, making soft, throaty calls. He sat deep in the nest mold, unmoving, but later got off the nest while she was down below and feeding. He’d been off for only two minutes when she went up to the nest to resume incubation and/or to lay the second egg.
As I tried to approach the nest at 9:40 A.M. to chase her off to check for a second egg, he got defensive for the first time. Indeed, his anger was downright intimidating. He puffed himself out, made the rapid kek-kek-kek alarm calls, and pounded the wood right next to me so hard that splinters flew. She, in turn, remained silent and refused to come off the nest. Was he feeling his testosterone? During breeding time, the testes of male birds increase in size more than thirty-fold. Testosterone supposedly increases aggression. But Houdi, presumably with little testosterone, was soon as aggressive toward me as Fuzz. She was so aggressive, I needed to resort to trickery to find out what was in the nest.
“Want to do an experiment?” I asked a friend who was visiting.
“Sure!”
“Okay—go up to the nest and see if there are two eggs in it.”
She did. And there were.
Neither bird tried to repel her. Neither made alarm calls. She had not interacted with the birds before, and should have been more threatening to them than I, who had raised them from chicks and whom they had trusted until that very moment. I wasn’t much surprised, through, because ravens are consistently surprising.