Reducing lead on the landscape: Anticipating hunter behavior in absence of a free nonlead ammunition program

Abstract

Lead is a neurotoxin that has been documented to affect many forms of wildlife, and has been identified as a limiting factor in a population of California Condors in Northern Arizona. The Arizona Game and Fish Department provides vouchers for free nonlead ammunition to hunters selected to hunt within the distribution of California Condors, with the intention of having fewer lead-laden offal piles available to California Condors. Although wildlife agencies may reasonably assume voucher programs motivate hunters into choosing nonlead ammunition, the lead reduction efforts attributable to the voucher program has not been empirically quantified. Our intention was to compare a control group of hunters to a treatment group of hunters within California Condor occupied areas. Both groups received educational materials regarding the deleterious effects of lead, but the treatment group also received a voucher for a free initial box of ammunition. About half of the control group used nonlead ammunition, compared to about three-fourths of the treatment group. Prominent barriers to adoption of nonlead ammunition included a general difficulty of obtaining it, obtaining it in the desired caliber, and its costliness. Frequently mentioned motivations for using nonlead was the exhortation to use it by the Department, and the desire to aid California Condor recovery by hunters. The disparate compliance rates found herein confirm and quantify the success of nonlead ammunition voucher programs, but underscore the importance of working to increase the supply of nonlead ammunition with the end of facilitating its procurement and reducing its cost.