A new study found that an increase in the number of prey available will not result to the number of predators. The findings suggest a new and unusual law of nature that could explain why the population of lions continues to decline despite the abundance of food for them.
Ian Hatton, the study author and a biologist at McGill University, analyzed the proportion of predators to prey across dozens of parks in East and Southern Africa to determine why the lion population is declining. His analysis revealed that in areas where the prey is abundant, the predators tend to reproduce less compared to areas where the prey were smaller. The pattern remained consistent in different ecosystems based on their analysis of more than 1,000 studies conducted in the past 50 years.
"Until now, the assumption has been that when there is a lot more prey, you'd expect correspondingly more predators," Hatton said in a press release. "But as we looked at the numbers, we discovered instead, that in the lushest ecosystems, no matter where they are in the world, the ratio of predators to their prey is greatly reduced. This is because, with greater crowding, prey species have fewer offspring for every individual. In effect, the prey's rates of reproduction are limited, which limits the abundance of predators."
This discovery provides new insight on the predator-prey pattern that would help conservationists monitor the endangered species. The researchers plan to continue the study by developing a theory that would further explain this pattern and create a model that could predict if an ecosystem is in trouble, according to The Washington Post.
The study was published in the Sept. 3 issue of the journal Science.
