Noninvasive sampling of mountain lion hair using modified foothold traps

Abstract

AbstractAlthough genetic analysis is an increasingly affordable option for wildlife studies, obtaining high‐quality samples from cryptic carnivores remains difficult. To address this, we modified and tested 20.3‐cm (8‐inch) foot snares in unbaited trail sets for noninvasive collection of hair samples from mountain lions (Puma concolor). We deployed 22 hair traps in the Black Range in southern New Mexico from May to November 2017, monitored by remote cameras, at 66 locations for 1,618 trap nights ( = 24.5 nights, SD = 7.2 nights). Photos indicated 20 instances of mountain lions passing within 2 m of a hair trap and we collected 7 mountain lion hair samples, which averaged >20 hairs/sample. All samples contained hair with visible roots and were identifiable to species; 6 of the 7 (85.7%) yielded sufficient DNA for individual identification. We attributed failure to obtain samples to 3 primary causes: individual trap saturation (2 instances), trap failure (2 instances), and non‐trigger events (9 instances). Black bears (Ursus americanus) and heavy rains were the primary sources of disturbance to hair trap sets, contributing to individual trap saturation and trap failure. We speculate that low trigger rates were associated with pan tension having been set too high in the first month of the study, as well as disturbance of hair traps or leading foot placements by nontarget species. We discuss strategies to increase hair sample collection rates, including seasonal use of hair traps, more selective placement on the landscape, and altering physical attributes of the hair traps. The quality of hair samples we collected and subsequent amplification rates indicated that, along with proper deployment strategies, hair traps are a viable tool for noninvasively collecting genetic material for individual identification of mountain lions and other elusive species.