Mind of the Raven: Investigations and Adventures With Wolf-Birds (24 page)

Some things, though, scared them at the same distance as strangers did: carrying a gun, wearing a long dress, and carrying a broom. The birds were then one and a half years old and no longer afraid of my regular clothes. Perhaps they recognized my consistent style or fashion. But a kimono? When I wore that, they flew up at fifteen yards, but it didn’t fool them for long. After my thirteenth approach in the kimono, they again allowed me to get next to them. They never allowed me to get close if I was carrying a broom, even though I had never chased or hit them with one.

I had not pinpointed any precise cues they used to identify me, or that they might use to identify each other. A big complication was that whenever I took away one cue I was really adding another. I could not just remove my face. I could only substitute. I concluded that the ravens recognize me without seeing my face and without identifying my clothes, although both cues are used when they are available and relevant. Presumably, the cues they use to identify each other are also multiple.

Vocal signatures are surely important in individual recognition, such as at a distance or when pairs make barely audible whispering-wimpering calls to each other when they are being intimate with each other. Males and females and dominants and subordinates have displays and vocalizations signifying sex and status, but none of that explains how they distinguish one another while they are engaged in the business of feeding, when, as the previous experiments indicated, they discriminate each other at a glance.

Can they recognize themselves in a mirror? We think of self-recognition as a higher mental faculty. It is not a faculty demonstrated in any bird. To the contrary, birds routinely and convincingly demonstrate their incapacity for self-recognition, by battering themselves aggressively against a mirroring surface, quite often until they bleed, in apparent attempts to dominate a rival. In North America, almost everyone with
a window to a dark cellar has had the experience of seeing a male robin or song sparrow bash himself against such a mirroring window every morning, sometimes for hours and many days in succession, during the breeding season. There is no evidence whatsoever that the unfortunate birds ever catch on to their misguided behavior, despite the repeated daily brutal punishment they give themselves.

Not even crows are immune to attacking themselves in the mirror. The May 12, 1996, Western Australia
Sunday Times
shows a picture of an Australian raven presumably “caught in the act” of vandalizing a car, although to me the bird appears to be attacking its reflection in the car window. Wondering how a dominant northern raven,
Corvus corax
, who always vigorously challenged every other dominant raven that he met would react to his image in a mirror, I planned to videotape Fuzz, the super-male, when he met his unyielding and identical match.

It was June 25, 1995, and for three days I had been involved in the very frustrating process of trying to videotape the raven’s reaction to itself in a 17" × 36" frameless mirror that a glass vendor had kindly donated expressly for this project. I had set up the mirror, but hid it behind a plywood panel of equal size. A dead chipmunk was tied to a stick in front of it. It took a full day before Fuzz, the boldest raven, ventured to yank at the chipmunk in front of the plywood hiding the mirror.

I presumed I could then pull the board away to reveal the mirror and stand back to film the show. Fuzz would want not only to impress any rival in the aviary, but also to repel any competitor daring to try to take his choicest food. What happened? As soon as I removed the plywood panel and the reflecting surface became visible, all the birds went bonkers. They retreated into their loft. After a few hours, they started begging piteously. They were hungry for chipmunk, yet they did not dare to come down to feed.

I tried again on July 5, and the results were almost an exact repeat of the previous week. I left the mirror set up with the plywood covering. The birds fed every day in front of the plywood, and were thoroughly habituated to feeding at that spot.

On September 20 at 7:02
A.M.
, I provided Fuzz, Goliath, Whitefeather, and Houdi with delicacies—chopped squirrel—at the usual place, but this time I exposed the mirror surface. The meat was within inches of the polished and unscratched mirror, and it was situated so that any bird walking up to it could see the “other” raven approaching from the opposite direction.

The birds looked down from their perches. They hopped back and forth nervously. At last, after fourteen minutes, Goliath descended to the ground, walked cautiously to the mirror, and took a piece of meat. Fuzz instantly chased him until he dropped the meat, but it happened to fall back in front of the mirror.

After four more minutes, Fuzz went to the front of the mirror and grabbed a piece of meat. Goliath then followed and got one, too. Next, the two females begged and received their food from their respective male partners. Curiously, neither male acted as though he saw what was
in
the mirror when he approached it.

On September 23, I again revealed the mirror, and they went to the food placed two inches from it within two minutes. They acted only slightly nervous. Even though all four birds stayed feeding directly in front of the mirror, they at no time overtly acknowledged anything they might have seen in the mirror. I was somewhat puzzled by these results. I could conclude that they didn’t attack the mirror reflections as they would if they saw strangers, but I didn’t think I could conclude they recognized themselves because they didn’t attack.

I tested another group of ravens at the same mirror on October 25. As before, when I first brought the mirror into the aviary and set it in front of plywood, the birds were afraid of it. I turned the reflective surface away to let them first get used to the mirror as a strange object. When I finally reversed the mirror after a week, to expose its reflective surface, they were again afraid, staying away from food placed in front of it. The next dawn, they came up to the mirror and took the food, appearing to ignore the images of themselves, as the other group had done; but then two of the six birds ambled back to mildly interact with the mirror. These two each peered into the mirror intently, bill to
reflected bill, then both repeatedly reached up with their feet as if trying to grab their reflected images. They were silent and they didn’t seem aggressive. These birds had been born that spring, whereas the first birds in the experiment were over two years old. I’m not claiming that age is relevant. I suspect it isn’t. It is just the only difference that seems tangible enough to mention.

Soon after I had made these observations, I received a call from a man in northern Maine named Matt Libby, who told me about a peculiar raven problem. For about a hundred years, his family had rented out wilderness camps, and there had never been any raven problem “until three or four years ago.” The problem was that one or two ravens perched on his camp porch railings, leaving considerable white deposits, tearing up his cedar wood chairs, hacking window framing to bits, and dirtying up the windows under the shaded porch. Ravens had always been around, he said, but they had never been a problem before. I asked if there was anything different now. There wasn’t, he said. Then he thought a bit and came up with one tiny detail: “Only that I’ve now got thermopane windows rather than single glazed panes.” I checked with glass merchants and learned that most thermopane sold these days is “very low reflective,” called “Low E.” It has a coating on the outside that allows heat waves in and then reflects them inside, so that less heat leaks out as radiation. Did that have something to do with the ravens under the dark porch attacking or being attracted to their reflected images in the camp windows? My data do not answer the questions with which I started, but they point to interesting studies that would be fun to do, not only with mirrors but with television screens. For the time being, I had to be—and was—content to observe ravens in the field, where they routinely make other, perhaps even more vital, identifications.

R
AVENS ARE FLEXIBLE
. T
HEY NEST
on pine trees in Maine’s inland wilderness, on tall beech trees in northern Germany, on power lines, on radar towers, on buildings above busy streets, under highway overpasses, in active railroad trestles and abandoned buildings. They’ve nested in the trunk of an abandoned car in the Mojave desert, and on a baseball stadium in Elmira, New York. There is even now an active raven nest under the MJ section of Penn State’s Beaver Stadium.

Whenever possible, ravens prefer to nest on rock shelves tucked under overhangs on cliffs. These are the same sites also preferred by some of their mortal enemies: golden eagles, gyrfalcons, and great horned owls. Strange as it may seem, raptors and ravens are often coinhabitants of the same cliff, sometimes nesting within yards of each other. Very often,
falcons and owls take over an old raven nest because the raptors cannot build their own nests. The ravens, when evicted from their nest, will often build another one nearby. Thus, ravens provide the raptor a nest.

In the city of Bern, Switzerland, ravens started nesting above the busy public square in the middle of the city on a large government building, the Bundeshaus, in 1988. By 1995, the raven pair had built five nests in different cornices of the building, and at least five pairs of falcons of two different species (
Falco tinnunculus
and
Falco peregrinus
) had moved in to use each of the nest places the ravens had constructed. In 1998, they still nested there, bringing off three young, and entertaining the townspeople.

The associations between nesting ravens and raptors, and between neighboring territorial ravens, are complex and “personal.” Relationships probably change with time as disputes are resolved, antagonisms subside, and truces develop. As one example of a truce among traditional enemies, I once had a tame great horned owl and two tame crows, all of whom lived free in the woods close around my cabin. Crows are one of the owl’s favorite and common prey. Their first encounters were tense, yet owl and crows eventually ignored each other altogether and peace was restored.

Raven nest on the Bundeshaus in downtown Bern, Switzerland
.

The raven-raptor association is not always one-sided. There is also advantage for ravens to associate with raptors, who often provide kills
from which to scavenge. Perhaps even more important, if one fierce species becomes tolerated near the nest, it becomes a “watchdog” for predators of the other, seeing and repelling strangers.

Most raven nests do not have a “dear enemy” guard, and at least one member of the raven pair stands guard at the nest at all times. In Denali Park in Alaska, I had the privilege of watching a raven nest with several half-grown young for a week at a cliff where I occasionally saw peregrines, gyrfalcons, and golden eagles fly by in the distance. No raptor nested on the cliff itself. One of the raven pair was always on guard to greet me loudly whenever I came near the nest. The second bird, summoned by the first’s commotion, would come immediately and join in the clamor. Then one day, one of the adults disappeared. Since the remaining bird had to leave the nest to forage, the young were sometimes left unprotected. After just one day, the young disappeared from that nest. Only a large raptor could have taken those young, since the nest was inaccessible from the ground.

Young ravens taking the measure of a turkey in my aviary
.

Ravens also come in contact with numerous other potentially dangerous birds at food. What follows is a set of observations of one raven, several crows, a turkey vulture, and two broad-winged hawks,
Buteo platypterus
, feeding at the same carcass near my Vermont house in 1994.

On April 2, I did my part like all the other people who feed birds in the winter. I laid out bird food. I put a dead, cut-open calf within sight of my bedroom window. The first birds came at dawn: three crows and
one raven. The raven was soon feeding and flying off with chunks of meat. The crows alternately perched in the trees and fed when the raven had left. The raven, the male of the pair that nests nearby, had already come to feed on my offerings here for a number of years. The female would now be incubating, and he daily brought her meat from this calf.

On April 3, one raven along with one crow and one turkey vulture came in the early morning. The vulture fed almost continuously for at least two hours in the presence of either the crow or the raven. As before, crow and raven fed alternately, but both fed alongside the vulture, acting as if it were invisible. The vulture in turn ignored both corvids.

Eight crows arrived in the early forenoon. As many as five of them fed simultaneously alongside the vulture, but all the crows left the bait whenever the lone raven came back to feed. Crows vigorously chase ravens one-on-one, especially in spring and summer, but sometimes also in the fall and winter. But here, none of the eight ventured onto the ground when the one raven was near. The raven paid no attention to the crows, nor have I ever seen ravens aggressive to crows or try to chase them away from bait.

The next day, eight crows and the raven were back, behaving like the day before.

On April 11, after I had been away for a few days the calf carcass hosted not only five crows, a turkey vulture, and two broad-winged hawks, but also one coyote. The latter left just as it was getting light, before the birds arrived.

Again, the crows flew up and did not feed when the ravens fed, but the crows fed amicably and without sign of alarm or caution directly alongside both hawk and vulture. The second hawk waited its turn perched in a tree, and fed only after the first had left. As always before, the raven took precedence over all. It unhesitatingly came down to feed regardless of whether a hawk was on the meat or on the neighboring tree; but when it fed, no crow, singly or in a crowd, ventured near this male raven. The raven never bothered to nip the tails of the hawks or the vulture next to it.

Ravens are well known to pull the tails of raptors near baits. Their reason for doing so is obscure, but their effects on the raptors are
clearer, though varied. In northern Arizona, recently released captive-reared California condors,
Gymnogyps californianus
, are provided with animal carcasses to feed on. Quite often, the condors are flushed from this food when golden eagles appear, and they may not come back for days. However, Amy Nichols, working for the Peregrine Fund on the condor project, reports that although ravens may “continuously torment the condors by pulling relentlessly at their feathers,” they also viciously mob any golden eagle that comes near. The eagles retreat from the ravens, giving the condors time to feed, while the condors are not displaced from the carcass by the ravens.

Ravens do not normally interact with chickens, but naive ravens may have no way of distinguishing them from eagles. What might they do with them? Our neighbor had a dozen Rhode Island Reds, each weighing almost twice as much as a raven, and I had my group of six ravens, six months in age. The chickens were past laying age, which is why my neighbor donated them in the name of science. She didn’t want to kill, pluck, clean, cook, and eat them herself. After I had tried one, I knew why. My ravens had hardier palates. They liked the first broiled chicken meat just fine. Before I planned to give them the rest raw, I decided first to find out how they would respond to them live.

When the first two chickens were let out of the burlap bag I’d brought them in, they cackled excitedly, walked slowly and deliberately, and seemed unconcerned about a mere six ravens that happened to gather round. The ravens started edging closer, walking sideways and crouching, enabling them to make an instant retreat, which they did whenever a chicken as much as took one step toward them. Within an hour, some of the ravens got bolder, managing to sneak up occasionally to yank on a tail feather. If a chicken ran, the raven hopped comically behind the cackling hen. Soon the ravens were interrupting their usual play with sticks and other objects to “count coup” with chickens. This activity continued almost ceaselessly for the whole day. Except for losing a few tail feathers, no harm was done to the chickens. The ravens became ever more disinterested and the hens became ever more nonchalant. Before two days had passed, they were
feeding alongside the ravens on a calf carcass. The ravens ignored them, making no attempt to chase them off “their” carcass, although they were often intolerant of each other.

To find out if the ravens became habituated to chickens in general, or just to these particular individuals, I replaced the first pair with two others. A new Rhode Island Red I released into the aviary at night seemed to be quite excited when it woke up the next morning to find ravens flying all around. This bird panicked, and it was briefly “tested” by the ravens as the other two had been initially. All the other hens I later provided were totally ignored.

The rooster was next—a robust black and white Plymouth with a brilliant red comb and wattles and a thick neck. He stood so tall, you’d think he would have toppled when I let him out of the bag. He spread his shoulders, flapped his wings, crowed six times, then ran to the hens. The ravens were unimpressed. They continued to play with sticks. The rooster acted as if the ravens weren’t there. Whenever he happened to walk near a raven, it scuttled or flew away. No raven “tested” him as they had the first two hens. Nor did they approach another confident chicken, a buff Orkinton. Had they generalized, realizing that despite their superficial differences, they were all just chickens?

I left one chicken in the aviary with the ravens for a month. The ravens always yielded to her, and never even tweaked her tail. Whenever food was provided that she and the ravens wanted, she walked up to it and they briefly scattered. This is not exactly the behavior one might expect of ravens, who boldly pull eagles’ and wolves’ tails, chase golden eagles, and feed among wolves at the kill.

Several months later, I provided them with two new Rhode Island Reds who were the same size and appearance as the others, but who were still young. One acted unsure of herself. The ravens drew closer. She panicked, and then all the ravens attacked her relentlessly. After two minutes and an apparent imminent slaughter, I felt obliged to remove her. Like an ostrich sticking its head in the sand, she had sought refuge by sticking her head behind a loose board. The other chicken, who was a highly confident individual, fed alongside them and was ignored.

The next trial was with an adult turkey of wild-type coloration. The huge bird, seeing the ravens, fluffed out to make herself look even bigger, fanned her huge tail wide, and while holding her head horizontal, hissed and walked slowly and deliberately. The six ravens couldn’t resist. In the first thirty minutes, they tweaked her tail a total of sixty-two times. I sampled four more half-hour periods over the same and the next day that I allowed the turkey to stay with them. The total tail-pulling contacts per half hour steadily dropped from sixty-one to forty-six, twenty-eight, sixteen, and then to two. Two ravens contacted the turkey forty times each, while one bird did so only once. Together, the six ravens snagged only about a dozen tail feathers.

On May 16, I presented them with a fat, brown-backed, calm, and confident gander. The six ravens immediately came off their perches to surround the goose. All were silent. They tried to sneak up on his rear, but the gander turned. All jumped back. One raven finally nipped at his tail. As the gander made a feint at her, her mate rushed in and also yanked the goose’s tail, but that was all that happened. In fifteen minutes, all the ravens had lost interest and wandered off. When I later let a tame Canada goose they knew well into their aviary—it had for two months wandered to the edge of their aviary—they attacked it vigorously at once. As with the unsure hen, I feared for its life and quickly removed it from them.