By Olivia Johnson
An increase in lion attacks in rural Tanzania threatens both local people and lion conservation efforts, scientists report today in Nature.
One lion was notorious for killing 40 people in the same village
A team led by Dr Craig Packer of the University of Minnesota compiled data on lion attacks spanning 15 years.
They found that scarcity of natural prey and abundance of bush pigs, a common crop pest, are the major factors contributing to lion attacks on humans.
They suggest limiting populations of bush-pigs may prevent further attacks.
The number of lion attacks has increased significantly since 1990, with more than 563 Tanzanians killed and at least 308 injured by lions in that time.
In rural areas, Dr Packer's team reports, "lions pull people out of bed, attack nursing mothers, and catch children playing outside".
The increase in attacks mirrors the dramatic rise in the Tanzanian human population, which grew by nearly 50% between 1988 and 2002.
Swelling human populations have expanded into wildlife areas and depleted the lions' natural prey, such as zebras and impala.
The new study found that attacks are most common in rural areas during harvest time when farmers sleep in their fields in makeshift huts to protect their crops from bush pigs.
When natural prey is scarce, bush pigs become a staple of lions' diets, attracting the animals into populated areas and increasing the risk of attacks on humans.
Dr Packer's team found that a lack of natural prey coupled with an abundance of bush pigs are common features of regions with high rates of lion attack.
As it is not realistic to relocate the human settlements or increase stocks of natural lion prey in these regions, the researchers suggest controlling the population of bush pigs may be the best strategy to prevent further attacks by the big cats.