Lion Population Bounce-Back After A Trophy Hunting Moratorium

The practice of trophy hunting inflicts heavy tolls on the already-scant lion populations of Africa. Trophy hunting targets male lions, especially those 5-6 years of age, causing age and sex imbalances in the population and disrupting the social organization of lion prides. Because there are significant financial incentives to continue trophy hunting, the practice is unlikely to be abolished soon.

Conservationists have suggested instituting moratoriums during which trophy hunting will be suspended to allow lion populations to recover. This study is the first to evaluate what effect a moratorium has on the demographics of lion populations, which would allow policy-makers to decide whether a moratorium is an effective strategy for bolstering dwindling lion populations in areas where trophy hunting is prevalent.

In this study, researchers measured lion survival and population growth before and during a lion hunting moratorium enacted by the Government of Zambia from 2013-2015.  Through intensive monitoring, the researchers were able to compile a database of lions in 21 prides and 24 male coalitions from 2008-2015. The age and sex of each individually-identified lion was also recorded. The researchers fit their data to statistical models of survival to determine how the pre-moratorium cohort fared after the moratorium, and what effects the moratorium had on the demographics (age and sex) of the lions.

The researchers’ findings confirmed that trophy hunting had a negative effect on male lion survival prior to the moratorium. Fortunately, the moratorium led to four encouraging changes in the population of Zambian lions:

• The number of first-year cubs is at the highest ever recorded.
• The age distribution of females has become more balanced (there are now more younger females, whereas before there were mostly elderly females).
• There are more adult males in the population than in any of the five years before the moratorium.
• The number of males of “harvestable” age has increased. “Harvestable” age refers to the age at which male lions are most coveted for trophy hunting purposes.

While the moratorium policy instituted by the Zambian government is controversial, this study shows it achieves the intended effect of recovering lion populations. Hunting moratoriums can lead to more sustainable hunting practices, which are in the interests of both trophy hunting communities (who will continue to have a source of revenue so long as the supply of male lions is intact) and conservationists (who will be assured that the demographics of lion populations are kept in check by the moratorium).

Of course, trophy hunting is not a favorable for lion survival overall and is not acceptable to virtually all animal advocates. However, based on its economic contributions, is unlikely to be abolished completely. This study presents regular hunting moratoriums as a promising compromise between trophy hunters and conservationists, to mitigate concerns about lion survival, sex ratios, and age distributions.