Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS

NOVA Online
NOVA menu (see bottom of page for text links)

Crocodiles
menu (see bottom of page for text links)

Photo of Dr. Leslie stomach-scooping a croc Wrestling with Crocs
An Interview with Dr. Alison Leslie

What's it like to capture an 18-foot Nile crocodile for research purposes? To touch its skin, smell its breath, hear its growl? How do you weigh a half-ton croc? Are you willing to do what it takes to find nests, determine its sex or pump out its stomach contents for study? Most important, how do you release it and keep all your body parts at the same time? Dr. Alison Leslie, a crocodile researcher at the University of Stellenbosch in South Africa, describes the often hair-raising aspects of studying the ecology and behavior of Nile crocodiles in South Africa's Lake St. Lucia.


NOVA: What would happen if you fell overboard amid a group of wild Nile crocodiles?

Leslie: It's definitely not something I'd want to happen to me. If it was winter and the water was cool and they weren't that hungry, you might be able to get away with a few scratches and bruises and perhaps the odd lost limb or two. But if it was a hot day and they were in a feeding frenzy, I don't think you'd have two seconds to remember your name.

NOVA: Did you ever have any close calls?

Photo of croc from head-on view Leslie: If I'd had a really close one I probably wouldn't be here right now. We got bitten a few times by the smaller crocs, those about one and a half meters (five feet). They can give you a pretty bad nip. Once a huge male charged our little aluminum boat. It was breeding season and we had obviously entered his turf. Luckily the driver was wide awake. He spun the boat around, and we took off. Most of the close calls were with hippos, actually.

NOVA: They're more dangerous?

Leslie: They're the number one animal killer, if you rule out the mosquito. Hippos come out of the water at night to graze, but, of course, they don't spend the entire night out of the water. We used to drive right over them, because you just don't see them. Often in the middle of the night you'll see those beady red eyes and prepare to noose what you think is a croc, and it turns out it's a little baby hippo parking next to mom, who you didn't see.

NOVA: I've heard that many attacks on people occur while crocs are defending their nests, yet you do your nesting surveys on foot. Isn't that dangerous?

Photo of group of people by croc and high reeds Leslie: It's pretty hair-raising at times, because to find the nest site you have to walk between the lake edge and the crocodile nest. Now, croc mothers defend their nests unbelievably well. But six or eight people, as we usually have when we do these counts, is too much for them, and they bolt for the water, because that's where they feel safest. You'll be walking along, making noise to scare them off the nest, but sometimes they don't hear you, and suddenly one will run right in front of you to get to the water's edge. You'll look up, and it'll be coming straight for you. You're carrying backpacks and tents and all sorts of equipment. You either run forwards or backwards as best you can, or you just jump. And they shoot on past you.


NOVA: They don't stop to bite you?

Photo of man measuring croc with a tape measure Leslie: I think that's the last thing on their minds. Because once they leave their nests they realize that you know that they're kind of vulnerable. All they want to do is get to the water. Sometimes, however, after the mother's left, you'll be standing on the nest taking measurements, and suddenly she'll come back. You have to remember that crocs can outrun you quite easily. For short bursts, they can run 35 kilometers an hour (18 mph), which is about what an Olympic athlete can do. And they can come out of the water even faster. If they've had time to build up speed, they can shoot themselves out of the water at 70 kilometers an hour (43 mph). It can be pretty terrifying at times.


Continue: Capturing a wild crocodile.



Outlasting the Dinosaurs | Who's Who of Crocodilians
Wrestling with Crocs | The Clickable Croc | Teacher's Guide | Resources | Transcript

Editor's Picks | Previous Sites | Join Us/E-mail | TV/Web Schedule | About NOVA
Watch NOVAs online | Teachers | Site Map | Shop | Search | To Print
PBS Online | NOVA Online | WGBH

© | Updated December 2003

Support provided by

For new content
visit the redesigned
NOVA site

Resources Clickable Croc Wrestling with Crocs Who's Who of Crocodilians Outlasting the Dinosaurs NOVA Shop Site Map Search NOVA Archive Teachers TV/Web Schedule TV/Web Schedule Feedback