Improving evaluation of nonlethal tools for carnivore management and conservation: evaluating fladry to protect an endangered species from a generalist mesocarnivore

Abstract

Carnivore conservation and management are global research priorities focused on reversing population declines of imperiled species and identifying more effective and humane management of generalist carnivores with thriving populations. Nonlethal methods to mitigate conflict are increasingly used to advance conservation objectives; however, there is limited knowledge about the effectiveness of many nonlethal methods. We tested a nonlethal tool (fladry), that serves as a barrier to deter wolves Canis lupus and coyotes Canis latrans, for its efficacy at preventing coyotes from using prairie dog Cynomys ludovicianus colonies, the primary prey for critically endangered black‐footed ferrets Mustela nigripes. We used camera trap data and an occupancy approach to evaluate the tool’s efficacy. We measured coyote response to fladry at both a coarse monthly scale (via use, attraction and avoidance probabilities) and a fine scale (via daily activity). Overall, use of areas inside exclosures declined by 60% after 60 days of fladry application and coyotes avoided some previously used areas both within and outside exclosures. Interestingly, coyotes were attracted to previously unused areas surrounding exclosures and increased activity around the periphery of fladry exclosures by 170% immediately after fladry installation, suggesting coyotes actively explored these areas and may have responded to fladry in a way that is counterintuitive to management expectations. Occupancy models provided more robust evaluation of fladry and revealed important behavioral responses relative to other common evaluation techniques (i.e. time until first detected crossing). Our results have implications for future development and evaluation of nonlethal tools for carnivore conservation and management globally.

Methods to mitigate human–wildlife conflicts involving common mesopredators: a meta‐analysis

“…Some other repelling mitigation methods that were not tested within the systematic review include pyrotechnics, effigies and scarecrows, sounds, bright or flashing lights, lasers, reflectors, shock collars, fladry and flags, gas guns, drones, motion‐activated devices, predator models, ultrasounds, hazing by humans, and high‐pressure water sprayers (Smith et al 2000, Baker et al 2007 b , Reidinger and Miller 2013, Blumstein 2016, Conover and Conover 2022). Fladry barriers seem effective against larger canids (Musiani et al 2003, Young et al 2019, Windell et al 2021); therefore, this might have potential against foxes.…”

Camera traps as a research method for carnivore population estimation: Strength, weaknesses, opportunities and threats, analysis and improvements

“…Camera traps are used to generate abundance indices (Beirne et al, 2021;Burton et al, 2012;Farris et al, 2014;Muench & Martínez-Ramos, 2016;Sollmann et al, 2013;Strampelli et al, 2020;Windell et al, 2022) 5. Pictures produced are aesthetically pleasing and can be used in research fundraising and awareness raising (O'Connell et al, 2011) 6. Can be used to evaluate other monitoring measures (Avrin et al, 2021;Comer et al, 2018;Nekaris et al, 2020;Palmer et al, 2021;Windell et al, 2022) Threats 1. Capturing non-target species (Kelly et al, 2012) 2.…”

Integrating robotics into wildlife conservation: testing improvements to predator deterrents through movement

“…Coyotes are the most important predator of livestock in the U.S. ( Knowlton, Gese & Jaeger, 1999 ; Mitchell, Jaeger & Barrett, 2004 ) and their range in North America has expanded tremendously in the past 50 years ( Hody & Kays, 2018 ; Poessel, Gese & Young, 2017 ). Coyotes are intelligent, generalist omnivores ( Gese, Ruff & Crabtree, 1996 ) and there has been extensive research on the development of new techniques for preventing coyote conflict ( Knowlton, Gese & Jaeger, 1999 ; Mitchell, Jaeger & Barrett, 2004 ), including the use of deterrents ( Linhart et al, 1992 ; Windell et al, 2022 ; Young, Draper & Breck, 2019 ). To our knowledge, no work has been done on coyotes that integrates the concepts of mobility for enhancing deterrent effectiveness.…”