The thicker vegetation, as measured by LiDAR, is where the males are making their kills. What's more, it's also the most difficult place to directly observe lions using traditional, low-tech methods of field researchers. So it's no wonder field biologists have had a hard time seeing this hunting behavior.
"For a very long time people have been putting radio collars on animals," commented conservation biologist Stuart Pimm of Duke University. "What is becoming exciting is that now we can now tie that information into a lot of other information" like the vegetation, as was done in this study. "You get information you couldn't get any other way."
When the GPS data indicated the lions were close together, it sometimes meant they were feeding on a recent kill. Another co-author on the paper, Craig Tambling of the University of Pretoria in South Africa, would then hike out and verified the kill on the ground.
Then back in California, Loarie and another coauthor, Gregory Asner, studied the data how the kill related to where the lions were beforehand. What they discovered is that the male lions are using thick vegetation to ambush their prey.