Behavioral Ecologist
Considered one of the world’s foremost experts on African lions, Dr. Packer is a Professor of Ecology, Evolution, and Behavior at the University of Minnesota. In 1986, He established the world’s first research center dedicated to the study of lions. Tune in to find out what makes the powerful yet vulnerable lion such a fascinating species to study.
STEM to the Sky
Nov 29, 2020
My name is Craig Packer. I’m a professor in the ecology department at the University of Minnesota in St. Paul. For most of my life, I’ve done research in Africa on large mammals. Initially, I worked with Jane Goodall on monkeys and apes, in Tanzania. I then worked in the Serengeti, also in Tanzania, on African lions for many years. For the last few years, I’ve been working more in southern Africa, in Namibia, Botswana, and South Africa.
When I was a child, I really thought it would be great to be a scientist of some sort and to be able to work outdoors. I spent my summers in a very small town in West Texas. It was a town, you might not believe it, called Noodle, Texas. My grandmother had a farm a few miles away from Noodle, and I used to spend my summers helping around the farm and just being kind of a country boy. Back then, I never heard of ecology and certainly didn’t know that people could study animals. It wasn’t until I was an undergraduate at university, that I even found out that you could go to Africa.
Then, there was an amazing day. During my sophomore year or junior year in college, I was taking an introductory biology class, and the professor said, “we’ve got this new deal where you can go to Africa and work as a field assistant.” I thought “Oh, that’d be fun” and so I went.
By the time I got over there, there was a new field of biology, which we now called behavioral ecology. The field of behavioral ecology asks the question “Why is an animal behaving a certain way?” When we ask this question, we’re actually asking, “How does it benefit?” Does it get more offspring? Is it more likely to survive?
I just thought it was so amazing. It allowed me to work outside in an area that I found intellectually really appealing, and so I just kept going.
When I was at Gombe, I was working on baboons. Baboons are usually very competitive with each other, but every now and then, a couple of individuals would team up and cooperate together. Cooperation was a rare concept in animals. So, one of the first papers that I ever wrote was about the circumstances where these male baboons would cooperate with each other.
At that time, I happened to have friends who had been in Tanzania as well who were studying lions. But, they were coming to the end of their grants, so they thought they should probably let people know that there would be an opportunity to take over the study of lions.
Lions, unlike tigers, leopards, pumas, and jaguars, are very sociable. They live in social groups called prides. Cooperation is something that has been of great interest to evolutionary biologists, including Darwin. His views seem to say that you should always be fighting and it’s all selfish. But then you do see examples like ants and bees where there is enormous cooperation.
Here was a cat, unlike all the other cats, that cooperated. My initial interest in lions was to study why they are so cooperative. There are the females forming these prides; they would even nurse each other’s babies. There are also the males who form a coalition and they “battle” against other males in groups. These are the ideas that attracted me to studying animals in the first place, so I spent about 16 years of my research on lions solely on these questions.
In 1994, there was this distemper outbreak that spread from the domestic carnivores, and it killed about 40% of the lion population in the Serengeti. From that moment on, I realized how vulnerable of a species lions are. Beginning in the 1990s, and for the following 20 years, I was working in the Serengeti on things that were relevant to their conservation.
It’s even more pressing today than it was 25 years ago, because the lion population now has declined quite a bit from what it used to be. The lion is a really difficult species to conserve, because they’re terrible, horrible, and awful animals. We look at diseases, we look at livestock killings, and even man-eating lions; all of these issues need to be addressed if the lion is to survive another hundred years in the wild.
When we started studying lions back in the 1970s, they were really not a conservation concern. For the first 15 years or so, we were all just interested in their basic ecology and their evolutionary pressures that might make them be cooperative or not. We kind of had the whole field of lions study to ourselves.
In 1986, I established The Lion Center at the University of Minnesota, where my students could come in and discuss research. Having a research center, we could try to look at lion behavior and conservation more comprehensively.
I. I wrote Into Africa in the 1990s when I was in Tanzania. I was a chaperone there for a couple of field assistants from England to do day-to-day monitoring of the lions. So, we were driving out, radio tracking, seeing where the lions were, and taking note of what they’re eating, etc. On that same trip, I also went back to Gombe because I was still collaborating with Jane Goodall on some of the aspects of monkeys and apes.
When I was explaining these things to the new field assistants, I thought, “I really should write all of this down before I forget it.” I wanted to have a record so that when my two kids grew up, they could see the kind of work that their parents did when they were small children and what life was like at Gombe and also with the lions.
At that point, I started keeping a ledger or diary. The book reads like a day to day account. It’s an experience; you’re learning how to go look for lions with me, seeing them for the first time, learning what to do when you get stuck in the mud, etc. With the monkeys, that was all on foot. You’re tearing through the brush with monkeys in the trees, climbing up hills, and going down valleys. It was all good fun on a moment to moment basis, so I just wanted to capture all of that.
II. I wrote a second book called Lions in the Balance when I started doing all of that conservation work. Often, conservationists come up against many pressures from business interests that have their own agenda, who almost always have a lot more power than the scientists.
One of the things that I was interested in, trying to conserve lions, was looking at the impacts of sport hunting or trophy hunting. Trophy hunting is a very controversial topic, so I was just trying to look at it objectively. If we ignore the animal rights questions in hunting and just ask the question, “Can trophy hunting give enough value to wildlife so that a very poor country like Tanzania will set aside all this land for nature rather than for farming?”
I wrote Lions in the Balance centered around my frustrations of trying to deal with this question back and forth. In theory, hunting could potentially give value to wildlife, but in practice there’s a lot of corruption and over-hunting. The answer is somewhere in the middle, which is not easy. That second book tackled this complicated problem, which was frustrating because people don’t always do the right thing for the future of wildlife conservation.
When people say “find your passion”, what they’re really saying is find something that you’ll be willing to really dig in and work hard at, month after month, year after year. You do kind of make your own luck. If you can successfully produce good outcomes, people will say that you know what you’re doing, and then you can keep going. It takes commitment and a focus, but it does help if you’re in a field that you genuinely want to pursue.
I. During a typical day in the Serengeti, I’d have a couple of research assistants who drive up and see the lions. They would record what they’re eating, their mating behaviors if any, if there are any new cubs, and where the lions are that day on the map.
Towards the end of my time working in the Serengeti, we had a large camera trap grid called Snapshot Serengeti. Everyday, my graduate student and field assistants would go out to make sure all the cameras were working and putting everything into a computer database. That would be a typical field day.
II. Back in Minnesota, I do all of my undergraduate teaching in the fall semester. After lecturing for many years, I finally realized that that was a really stupid way to try to teach somebody something. I was an early adopter of what’s called a flipped classroom. I recorded my lectures one last time on video. The videos are broken up into little chunks online. Before students come to class, they watch the recordings. During class, we talk and do a couple of activities; it’s all very interactive.
My graduate students work with undergraduates who help them with some of the data that they’re analyzing. As I mentioned, Snapshot Serengeti is essentially a grid of cameras set out in a checkerboard in a big area. Through the cameras, we can see how the animals are moving around. We now have 40 different camera trap grids in various countries in Africa in a much bigger project called Snapshot Safari. We ask people to go online to look at the photos from each grid, and students and other “citizen scientists” from all over the world help identify the species of animal in each photograph. Over time, we use the photos to estimate how many animals live in each wildlife reserve. This is something that can help wildlife managers learn whether their conservation strategies are working. Snapshot Safari is a way that anyone, anywhere, anytime, can go on the internet and help us to see how well the animals are faring in these different reserves.
I have a graduate student who is interested in the neurological basis of cooperation in lions. If you look at animals, neurologically, you can see actual differences in their brains depending on the kind of social system they have.
One of the most famous studies on this is in little rodents called voles. There’s a particular kind of vole that is monogamous, and there’s a closely related species that is polygynous. It turns out that the monogamous voles have a lot of receptors in their brains that are highly sensitive to the oxytocin burst (hormone of affection) they get from cuddling up to their mates whereas the polygynous voles have far fewer oxytocin receptors.
My graduate student is looking at the physiology of the lion’s brain to see if they are more like those monogamous voles. She will eventually look at the brains of lions as compared to the brains of leopards and cheetahs. Leopards are very solitary and hostile to each other. Lions, on the other hand, might get up, walk a few steps to one of its pals, and rub its head against the other ones. They must be getting that oxytocin rush. She has also been working with captive lions in South Africa. At feeding time, the lions would come up to the fence to sniff a little scrap of meat, and she has these little perfume sprayers that she uses to spray oxytocin up their nostrils, and it makes them even more affectionate.
Once the COVID shutdown is over, she will do the same thing with cheetahs and leopards, who are much more solitary. The hypothesis is that if she gives a squirt of oxytocin to the leopards, they’ll still be fairly obnoxious to each other because they have fewer receptors in their brains to detect the chemical.
I. If you could get excited by watching bugs or birds, listening to frogs in your backyard, or crickets, it will make your life much easier in terms of the scope of getting work done. Going to Africa, we have to pay for airfares, get permissions for working in foreign countries, and pay a lot of fees –– all of which makes everything quite difficult.
For students today, if you have a special interest in the conservation or daily lives of any sort of plant or animal, that might just be what you need to really get yourself going as a future conservationist or ecologist. You don’t have to worry yet about where you’ll eventually end up, but if you find yourself interested in a particular organism, that’s a good place to start.
II. One piece of advice I give to undergraduates or high school students is to volunteer somewhere. I’ve had high school students come to work with us in The Lion Center in St. Paul. If you have an opportunity to spend time in a research lab or field station, then get yourself out there and connect. Be around people who are practitioners. If you see what it’s like and what people are doing in a certain field, that might be the turn-on you need to determine where you want to go with something. If you can, I highly recommend connecting with any activity at a college or university even when you’re still in high school; see where it leads you!