Human-wildlife conflict is a serious issue that can simultaneously threaten human lives and livelihoods while also demonizing wildlife, leading to over-hunting and persecution. American alligators (Alligator mississippiensis) are the largest and most abundant apex predators in the southeastern US, and their populations have made remarkable recoveries after nearing extinction in the mid-20th century. However, these recoveries have been accompanied by an increase in human-alligator conflict, especially in Florida. Alligator attacks usually increase as temperatures rise seasonally, creating concern that climate change may exacerbate such conflicts and harm both humans and alligators in the process. We investigated the relative contributions of four potential drivers of human-alligator conflict (temperature, precipitation, human population size, alligator population size) using pairwise and stepwise regression techniques. Our goal was to determine if abiotic factors or human/alligator behavioral factors play a larger role in generating human-alligator conflict.
Results/Conclusions
Using simple pairwise linear regression, we found that only human population size was a reliable predictor of alligator attack rates in Florida during the period 1988-2016. Forward and backward stepwise regression produced identical results: models that included human population size performed much better according to Akaike’s Information Criterion (AIC) than models that did not include human population size. Including alligator population size slightly improved model performance according to AIC, while including temperature or precipitation did not improve model performance at all. Our results suggest that the increase in human-alligator conflict in Florida has not been driven by changes in abiotic factors over the past 30 years, and that increasing human population size accounts for much of the observed shift. As a result, management of human-alligator conflict should focus on limiting human-alligator interactions and preventing the further development of areas used by alligators.