Science for everyone

Does predation increase with habitat fragmentation?

April 14, 2014

Does predation increase with habitat fragmentation?

As forests are fragmented by humans, the amount of edge habitat increases

As forests are fragmented by humans, the amount of edge habitat increases. More edge habitat may allow predators, including those that prey on bird eggs, to easily penetrate otherwise undisturbed environments.

Michelangelo Ball Van Zee, a biology undergraduate at Princeton, tested that idea during the tropical forest biology course of the STRI-Princeton field semester. At three forest sites, he placed pairs of clay eggs in simulated nests along roads and deeper inside the forest to compare forest edge and interior. His results varied significantly depending on the site.

There were no significant differences between roadside and interior predation at the relatively isolated San Lorenzo National Park. At Panama City’s Metropolitan Park, there was interior predation, especially from birds. “This could be due to the ability of birds to penetrate the thick undergrowth at the site combined with heavy traffic along the trail deterring predation at nearby nests,” said Ball Van Zee.

Predation was highest along Pipeline Road, in Soberanía National Park. “Potentially, there aren’t large carnivores to keep rodents and birds in check,” said Ball Van Zee, pointing to human pressure on predators.

Other students carried out experiments on ants, termites, and mutualisms under the guidance of STRI’s Yves Basset. “I’m testing the students’ ability to get organized and do something feasible,” he said. “Hardly any have written a scientific report. Back in Princeton, they say usually the students who take the course here write better reports than those who didn’t take the course.”


PrintPrint article   ArchiveMore articles   Send your commentsComments