Vintage Technique Reduces Poaching in Serengeti National Park

"Expanded budgets and antipoaching patrols since the mid-1980s have significantly reduced poaching and allowed populations of buffalo, elephants and rhinoceros to rebuild,” states the authors of a paper published in today’s issue of Science.

This technique has been used since the 1930s to estimate the abundance of fish. Now, a recent study has proved for the first time that enforcement patrols are effective at reducing poaching of elephants, African buffaloes and black rhinos in the Serengeti National Park in Tanzania.

"Wildlife within protected areas is under increasing threat from the bushmeat and illegal trophy trades," says Ray Hilborn, University of Washington professor of aquatic and fishery sciences and lead author of a paper, "and many argue that enforcement within protected areas is not sufficient to protect wildlife. Some say the $2 million spent annually in the Serengeti on patrols would be better spent on other preventive activities."

However, his research proves otherwise. "The animals are 'telling' us poaching is down now that there are 10 to 20 patrols a day compared to the mid-1980s when there might be 60 or fewer patrols a year." Hilborn says.

Previously, estimates of poaching have been difficult to verify. Therefore, Hilborn and his co-authors used the decades-old technique of catch-per-unit-of-effort, which has been to estimate fish abundance and set fishing limits.

The Serengeti has a 50-year-record of arrests and patrols. To estimate the amount of poaching, the paper’s authors divided the number of poachers arrested by the number of patrols a day, assuming that arrests per patrol were representative of poaching intensity.

"We show that a precipitous decline in enforcement in 1977 resulted in a large increase in poaching and decline of many species," Hilborn and his co-authors wrote.

A press release announcing these findings stated:

The work marks the first time anyone has been able to reconstruct a history of poaching going back as far as 50 years, says Tom Hobbs, professor of ecology at Colorado State University and who is not affiliated with the work being published in Science.

"The Hilborn team has shown that protection of wildlife by active enforcement of laws and regulations remains an essential tool for conserving biological diversity," Hobbs says. "This sounds so simple, but it has been controversial."

The National Science Foundation funded, at least in part, the research.