Impacts of exclusion fencing on target and non‐target fauna: a global review

Abstract

Exclusion fencing is a common tool used to mitigate a variety of unwanted economic losses caused by problematic wildlife. While the potential for agricultural, ecological and economic benefits of pest animal exclusion are often apparent, what is less clear are the costs and benefits to sympatric non‐target wildlife. This review examines the use of exclusion fencing in a variety of situations around the world to elucidate the potential outcomes of such fencing for wildlife and apply this knowledge to the recent uptake of exclusion fencing on livestock properties in the Australian rangelands. In Australia, exclusion fences are used to eliminate dingo (Canis familiaris dingo) predation on livestock, prevent crop‐raiding by emus (Dromaius novaehollandiae), and enable greater control over total grazing pressure through the reduction of macropods (Macropodidae) and feral goats (Capra hircus). A total of 208 journal articles were examined for location, a broad grouping of fence type, and the reported effects the fence was having on the study species. We found 51% of the literature solely discusses intended fencing effects, 42% discusses unintended effects, and only 7% considers both. Africa has the highest proportion of unintended effects literature (52.0%) and Australia has the largest proportion of literature on intended effects (34.2%). We highlight the potential for exclusion fencing to have positive effects on some species and negative effects on others (such as predator exclusion fencing posing a barrier to migration of other species), which remain largely unaddressed in current exclusion fencing systems. From this review we were able to identify where and how mitigation strategies have been successfully used in the past. Harnessing the potential benefits of exclusion fencing while avoiding the otherwise likely costs to both target and non‐target species will require more careful consideration than this issue has previously been afforded.

The effects of site preparation equal those of seeding at a dryland restoration site: 6 years of plant community development

“…Livestock grazing, a common land use type in dryland ecosystems, can be difficult to manage as areas needing restoration cross ownership and jurisdictional boundaries. This is because the cessation of grazing impacts livelihoods and/or food security while livestock‐proof fencing can be prohibitively expensive to install, maintain, and remove as well as impact animals other than livestock (Smith et al 2020). Livestock grazing often co‐occurs on lands simultaneous with the process of restoration.…”

Expansion of Vertebrate Pest Exclusion Fencing and Its Potential Benefits for Threatened Fauna Recovery in Australia

“…Cluster fencing may also have adverse effects on native species, such as barriers to movement and gene flow. However, many these adverse effects also occur in conservation fencing [10]. With appropriate monitoring and use of mitigation strategies (such as metapopulation management), these adverse effects can be minimised to ensure net positive outcomes.…”

“…Exclusion fencing has also been utilised globally for the benefit of agricultural industries, excluding pest species that economically affect productivity. The applications of these fences have been broad and include fencing multiple species out of large portions of countries and continents [9,10] through to fencing single species out of small exclosures [11][12][13][14].…”

Animal Harms and Food Production: Informing Ethical Choices

“…There are many examples of studies documenting negative animal welfare impacts of fencing [ 112 , 113 , 114 , 115 ]. Fencing imposes direct harms on wildlife accidentally caught or entangled in fences ( Figure 1 a), whereby susceptible species regularly die or require rescue [ 116 ].…”