I would like to tell you about my first wilderness encounter with a black bear. It is something of a quaint and curious tale, and incidentally had a substantial impact on my understanding of the nature of animal intelligence.
The black bears of the Sierra Nevada are famous for stealing food. Black bears very rarely attack people, and fatal encounters are almost unheard of, but they are certainly good at acquiring people’s food. Nowadays backpackers who travel in the most popular parts of the Sierra Nevada are required to keep their food in bear-proof plastic canisters, but before those canisters came into widespread use, protecting food could be quite a challenge. Everybody who backpacked in those days heard lots of bear stories, some of them quite remarkable—for example one man told me about seeing a mother bear lift up her cub so that it could reach a food bag that she wasn’t tall enough to get at. My personal opinion is that most of those stories are bullshit, and that the majority of bear encounters are like what happened to me—too embarrassing to describe honestly.
The following events took place in July of 1983. I was a graduate student, and during my summer break decided to do a short hike across the Sierra Nevada crest, starting at Road’s End in King’s Canyon National Park, and coming out on the east side at Kearsarge Pass. When I made that plan, though, I wasn’t aware that I was headed toward a mountain range that had just experienced the snowiest winter on record. The high passes were still snowed in, even in July; the trail had been severely damaged by a huge mudslide; and because their usual food sources were snowed in, the local black bears were very skinny and desperately hungry.
I finally learned about the conditions when I got my trail permit at the King’s Canyon Ranger Station, but decided to go ahead anyway. I hiked up along the Bubb’s Creek Trail, which ascends steeply along the floor of a canyon surrounded by spectacular granite cliffs rising thousands of feet. After two days, and various challenges that I will skip over, I arrived, very tired, at Vidette Meadow, a lush and lovely spot at an altitude of 9500 feet. I had the campsite there all to myself.
Before going on with the story I need to explain how backpackers protected their food from bears in those days. The best and easiest method was to use a “bear box”—a heavy steel box bolted to the ground. Most backcountry campsites didn’t have one, though. Without a bear box—and prior to the invention of portable bear canisters—the only reliable way of protecting food was a method known as “double bagging”. Here is what you were supposed to do:
- Start by finding a tree that has a long thick horizontal branch, ideally about 20 feet above the ground. The branch should be stout enough to hold up all your food, but not stout enough for a bear to walk along.
- Divide your food into two bags.
- Tie one end of your rope to a small rock or something, and throw it over the branch. Done correctly this leaves you with the rope slung over the branch and the two ends free for you to work with. (Done incorrectly, your rope gets snagged in the tree and you have big trouble.)
- Tie one end of the rope to one of the two food bags. Then haul on the other end of the rope to pull the bag up to the branch. This can be very difficult, because the friction of the rope on the branch is unbelievable—you pull as hard as you can, and all that happens is that the branch bends. The only way to make it work is usually to throw the bag up as high as you can, then reel in the rope as rapidly as you can. It’s a lot easier if a second person is available to help, but even then getting the bag all the way up to the branch is hard.
- Now hold the second bag as high off the ground as you can, and tie the rope to it. Then push this second bag upward, allowing the first bag to slide down, until both bags are at the same height. Ideally you end up with both bags about 10 feet above the ground, but in real life if you manage 8 feet you’ve done very well.
The advantage for the double-bagging method is that if it is properly done, there is no part of the system that a bear can get at—it can’t reach the food bags, and it can’t reach any part of the rope. The disadvantage is that it’s a tremendous pain in the ass. Just how much of a pain in the ass is hard to understand if you haven’t had to do it. In practice, lots of people would get frustrated and finally opt for a simpler “single bag” method—that is, they would put all the food into a single bag, lift it up high enough so that a bear couldn’t reach it, then tie off the rope to a tree somewhere in the vicinity, hoping that a bear would not be able to figure out the geometry of the support system. And, for reasons that will presently become clear, many of those people ended up losing their food.
One further point about double-bagging, and then I can go on. The standard method, as I described it, requires throwing the rope over a tree branch. But some popular campsites were provided with a “bear cable”—a moderately thick steel cable running horizontally between two trees, 15 to 20 feet above the ground. This made double-bagging easier by allowing the rope to be thrown over the cable rather than a tree branch. Vidette Meadow, where I camped, had a bear cable of this type.
Continuing with the story, I staggered into the campsite, threw down my pack, and proceeded to set up camp. I took all the stuff out of my pack, threw my bear-rope over the cable (leaving the ends dangling free with nothing attached to either of them), and built a small campfire.
And presently, as I was sitting next to my campfire relaxing, a bear came strolling up the trail and walked into my camp.
It actually took me a few moments to realize that what I was seeing was a bear. Its fur was reddish (many black bears are not actually black), it wasn’t all that large, and it was much less stout than I expected a bear to be. It almost looked more like a huge Irish Setter than a bear. But it was definitely a bear.
This being my first encounter with a bear, I naturally got a bit excited. My first thought was that the bear might try to drive me away from my food, which was all lying on the ground next to me, so I pulled a burning stick out of the fire and started waving it at the bear and shouting curses at it. The bear did not appear to be particularly impressed. More or less ignoring me, it walked up to my rope (which, as I said, was slung over the steel cable with nothing yet tied to it), grabbed the rope with its mouth, and started yanking and tugging on it.
This behavior—chewing on a rope that wasn’t tied to anything—struck me as odd, but I didn’t figure out its significance until later. For the moment I just kept shouting at the bear and waving my burning stick. After a minute or so the bear gave up on the rope, then started walking back and forth indecisively, as though trying to figure out what to do. A few more minutes of this—at least that’s how I remember it—and then the bear turned and walked out of camp.
That was the last I saw of it—for that day.
Presently I calmed down. The afternoon wore on into evening, and I proceeded to set up my tent and sleeping bag, and fix dinner and eat it. While I was doing all this, I naturally spent a good bit of time thinking about the bear. In particular I thought about its strange behavior with the rope, and it gradually dawned on me that I had accidentally learned something important.
What I realized is that the great success of bears in obtaining food—the fact that no method other than double-bagging was effective against them—was not necessarily a sign of great intelligence. All that the bears really needed to do was learn one simple rule: if you see a rope, mess with it. Following that rule frequently yields food, and it doesn’t require any deep understanding of geometry. No matter how intricate the routing of the rope, if it is broken at any point, the food becomes available. The only method that protects against this strategy is double-bagging, because it is the only method that does not allow the bear to get at any part of the rope. All of the cleverness of people in inventing intricate food-hanging systems goes for naught, because—I realized—bears don’t have to be clever to defeat the system. They only have to be persistent—trying one stupid thing after another, and following a few simple rules such as messing with any accessible rope—until finally something works.
Anyway, after finishing my dinner, I divided my food into two stuff-sacks and hung it, using the double-bagging method as described. The result was not particularly satisfactory—it didn’t seem like the bags were as high off the ground as they ought to have been—but I was tired and didn’t have the energy to take the bags down and go through the process all over again.
Darkness came, and I went into my tent—about 50 feet from the food bags—crawled into my sleeping bag, and eventually fell asleep.
Sometime near sunrise I woke up, hearing noises, as of something large moving around. I fumbled for my glasses, poked my head out of the tent, and saw that the bear—the same bear from yesterday—was standing directly under my food bags, looking up at them. And it was dismayingly obvious that all the bear had to do was stand up on its hind legs in order to reach them. They were not nearly high enough.
I knew I had to do something quickly. I shouted at the bear, pulled on my pants and shoes as quickly as I could, and scrambled out of the tent. I then advanced on the bear, screaming curses at the top of my lungs and waving my arms around.
The bear gave a snort, lowered its head, and came charging at me.
If I had known as much about black bears then as I do now, I would have recognized this as a bluff charge, and I might have continued trying to drive off the bear. Maybe. But at that time I didn’t know anything about bluff charges, and I thought that the bear was seriously proposing to attack me. I immediately stopped advancing, and started slowly backing away, continuing to face the bear. I didn’t feel afraid, in fact I felt a total icy calm. But all my bravado vanished in an instant.
I backed away, and the bear stopped charging, turned around, and walked back to the food. Again it stood underneath the bags, looking up at them but not standing up to grab them. I just stood there watching. My attitude at this point was basically that the situation had passed beyond my control, and whatever was going to happen was going to happen.
After standing there for a few moments staring up at the food bags that it could easily have reached merely by rising up on its hind legs, the bear walked over to one of the trees that the cable was attached to, and proceeded to climb it. It climbed up to the level of the cable and then stopped there, looking out toward the food. There was absolutely nothing useful it could do from there, and after a minute or so it climbed back down. Meanwhile I stood there watching, feeling helpless.
The bear now finally walked back to the food bags, stood up on its hind legs and grabbed one of them, pulling it down and quickly working it free from the rope. It picked up the bag and carried it off into the woods, a couple of hundred feet perhaps, and sat down to enjoy a feast.
While the bear was busily chomping, I packed up my camp site. By the time I was done, the bear was done too, and ambled off into the woods. I then had the pleasure of cleaning up the wretched refuse—shredded paper, ripped containers, etc. I packed everything up and then spent the rest of the day hiking back down the canyon to Road’s End.
Let me recapitulate the moral of the story. Even though the bear ultimately got my food, it did not at any time do anything that I would call intelligent. In fact most of the things it did were stupid. It spent several minutes chewing and tugging on a rope that obviously did not have anything attached to it. It spent quite some time standing underneath food bags that it could have reached simply by standing up. It climbed a tree that gave it no ability to do anything useful. The general impression was that the bear was not making any effort to figure things out, instead it was just trying one random thing after another in hopes that something would eventually work. And eventually something did, but it was because of my ineptitude, not because of the intelligence of the bear.
Now obviously my data here are limited, and maybe this was just a particularly stupid bear. I have had several other bear encounters in the meantime, and none of them gave me any impression of brilliant intellect. But this is all anecdotal, and maybe there are indeed a few Einstein-bears out there—bears that can actually figure things out. Maybe. I’ll need to see solid evidence before I believe it, though.
It’s not that I don’t believe in animal intelligence. I believe in the continuity of nature, and if humans can be intelligent, then other species ought to be able to—the difference should be quantitative, not qualitative. Monkeys can certainly do clever things sometimes. So can other animals such as dogs; on the other hand I’ve seen plenty of dogs fail to solve extremely simple problems.
In my career as a neuroscientist I’ve spent quite a bit of time working with rats, and I’ve frequently been amazed at their ability to solve problems in ways that I didn’t expect. But that isn’t a result of intelligence. Rats are incredibly stupid—it takes them hours of training to learn to go toward a light in order to obtain a reward, something that humans learn in a single trial. Rats, like bears, succeed because they keep trying—they do one random thing after another until eventually something works, and when something works they tend to repeat it, and eventually this leads to functional behavior. Most animal problem-solving, I’m convinced, works the same way.