On this side of the fence: Functional responses to linear landscape features shape the home range of large herbivores

Abstract

1. Understanding the consequences of global change for animal movement is a major issue for conservation and management. In particular, habitat fragmentation generates increased densities of linear landscape features that can impede movements.2. While the influence of these features on animal movements has been intensively investigated, they may also play a key role at broader spatial scales (e.g. the home range scale) as resources, cover from predators/humans, corridors/barriers or landmarks. How space use respond to varying densities of linear features has been mostly overlooked in large herbivores, in contrast to studies done on predators.Focusing on large herbivores should provide additional insights to understand how animals solve the trade-off between energy acquisition and mortality risk.3. Here, we investigated the role of anthropogenic (roads and tracks) and natural (ridges, valley bottoms and forest edges) linear features on home range features in five large herbivores. We analysed an extensive GPS monitoring database of 710 individuals across nine populations, ranging from mountain areas mostly divided by natural features to lowlands that were highly fragmented by anthropogenic features.4. Nearly all of the linear features studied were found at the home range periphery, suggesting that large herbivores primarily use them as landmarks to delimit their home range. In contrast, for mountain species, ridges often occurred in the core range, probably related to their functional role in terms of resources and refuge.When the density of linear features was high, they no longer occurred predominantly at the home range periphery, but instead were found across much of the home range. We suggest that, in highly fragmented landscapes, large herbivores are constrained by the costs of memorising the spatial location of key features, and by the requirement for a minimum area to satisfy their vital needs.

Identifying the environmental drivers of corridors and predicting connectivity between seasonal ranges in multiple populations of Alpine ibex (Capra ibex) as tools for conserving migration

“…By contrast, none of the landmarks tested seemed to be used by migrant ibex as compass for navigation during migration. Yet, recent studies revealed how natural landscape features can be used by mountain ungulates, including Alpine ibex, to delimit their seasonal home ranges and constitute cognitive maps to gather and memorize spatially explicit information for navigation (Seigle-Ferrand et al, 2022).…”

Don't stop me now: Managed fence gaps could allow migratory ungulates to track dynamic resources and reduce fence related energy loss

“…We recorded crossings for all three species, with eland and springbok regularly trespassing the VCF. Permeable fences are often crossed by ungulates and other wildlife (e.g., Kesch et al, 2014Kesch et al, , 2015Dupuis-Desormeaux et al, 2018;Jones et al, 2019;Seigle-Ferrand et al, 2021), although their movement patterns are affected (e.g., McKillop and Sibly, 1988;Harrington and Conover, 2006;Sawyer et al, 2013;Laskin et al, 2020;Wilkinson et al, 2021). Permeable fences may not act as a general barrier but as an obstacle which leads to altered behavior and, consequently, energy expenditure.…”

“…They fragment habitats, shape environments (e.g., Pirie et al, 2017), cause injuries and mortality to wildlife (e.g., Harrington and Conover, 2006;Mbaiwa and Mbaiwa, 2006;Aquino and Nkomo, 2021;McKay et al, 2021) and impede animal movements across various temporal and spatial scales. Short-term foraging (Vanak et al, 2010) and seasonal migratory movements (Sawyer et al, 2013;Nandintsetseg et al, 2019;Seigle-Ferrand et al, 2021) are constrained, redirected to less suitable habitats, or even eliminated by fences. This holds especially true for wild ungulates, as many species track resources across vast areas by following landscape-wide wavelike greening patterns (e.g., Bischof et al, 2012).…”

“…Effects of fences on resource-tracking ungulates are increasingly studied and this substantially improves the knowledge within the emerging discipline of fence ecology. For instance, studies show that even permeable fences affect ungulate home range formation (e.g., Sawyer et al, 2013;Seigle-Ferrand et al, 2021;Robb et al, 2022) and that ungulatefence interactions peak during specific times (e.g., green season: Xu et al, 2021, day time: Wilkinson et al, 2021. Still, our ability to predict peak times of animal-fence encounters, and our understanding of energetic gains caused by permeable fence lines during resource-tracking are limited.…”

Understanding anthropogenic impacts on zoogeochemistry is essential for ecological restoration

“…Here, we define four broad categories. Physical and disruptive barriers: static human infrastructure such as fences, roads, towns, and dams directly reduce animal movement, increase habitat fragmentation, and reduce ecosystem connectivity (Jakes et al 2018). Even where physical barriers do not exist, disruptive linear features in the landscape, such as roads, have been shown to reduce animal home‐range size (Seigle‐Ferrand et al 2022). Where animals congregate in large numbers, C storage and N fixation can be impeded (Veldhuis et al 2019 b ).…”