Landscape connectivity among remnant populations of guanaco (Lama guanicoe Müller, 1776) in an arid region of Chile impacted by global change

Abstract

Connectivity between populations plays a key role in the long-term persistence of species in fragmented habitats. This is of particular concern for biodiversity preservation in drylands, since water limited landscapes are typically characterized by little suitable habitat cover, high habitat fragmentation, harsh matrices, and are being rapidly degraded at a global scale. In this study, we modelled landscape connectivity between 11 guanaco Lama guanicoe populations in Chile’s arid Norte Chico, a region that supports the last remnant coastal populations of this emblematic herbivore indigenous to South America. We produced a habitat suitability model to derive a regional surface resistance map, and used circuit theory to map functional connectivity, investigate the relative isolation between populations, and identify those that contribute most to the patch connectivity network. Predicted suitable habitat for L. guanicoe represented about 25% of the study region (i.e., 29,173 km2) and was heterogeneously distributed along a continuous stretch along the Andes, and discontinuous patches along the coast. As a result, we found that high connectivity current flows in the mid and high Andes formed a wide, continuous connectivity corridor, enabling connectivity between all high Andean populations. Coastal populations, in contrast, were more isolated. These groups demonstrate no inter-population connectivity between themselves, only with higher altitude populations, and for two of them, animal movement was linked to the effectiveness of wildlife crossings along the Pan-American highway. Our results indicate that functional connectivity is an issue of concern for L. guanicoe in Chile’s Norte Chico, implying that future conservation and management plans should emphasize strategies aimed at conserving functional connectivity between coastal and Andean populations, as well as the protection of habitat patches likely to act as stepping stones within the connectivity network.

Evaluating the role of body size and habitat type in movement behavior in human‐dominated systems: A frog's eye view

“…For instance, some forest‐associated species orient away from agricultural fields, clear‐cut forests, or roads, which may be attributed to less vegetation structure, lack of available cover, and/or increased desiccation risk (Cline & Hunter, 2014 ; Martin et al, 2020 ; Rothermel & Semlitsch 2002 ; Schwarzkopf & Alford, 1996 ). These avoidance behaviors can strongly affect the movement of individuals, limiting movement for resource acquisition, predator avoidance, and population connectivity (Espinosa et al, 2018 ; Olah et al, 2017 ; Peterman et al, 2014 ). While many instances of land‐use change can generate barriers and create a habitat matrix that restricts movement through unfavorable habitats (Gibbs, 1998 ; Kuefler et al, 2010 ), habitat change can also connect other populations (Öckinger et al, 2012 ; Youngquist & Boone, 2014 ).…”

“…For instance, some forest-associated species orient away from agricultural fields, clear-cut forests, or roads, which may be attributed to less vegetation structure, lack of available cover, and/or increased desiccation risk (Cline & Hunter, 2014;Martin et al, 2020;Rothermel & Semlitsch 2002;Schwarzkopf & Alford, 1996). These avoidance behaviors can strongly affect the movement of individuals, limiting movement for resource acquisition, predator avoidance, and population connectivity (Espinosa et al, 2018;Olah et al, 2017;Peterman et al, 2014).…”

Temperature as a constraint on the timing and duration of African elephant foraging trips

“…Individual space-use strategies become critical when animals face water scarcity. Most large herbivores living in arid and semi-arid environments worldwide only can find drinking water in sparsely distributed water sources such as water pans (Cain III et al 2006;Cornélis et al 2011;Espinosa et al 2018;Gedir et al 2016;Redfern et al 2003;Reyna-Hurtado et al 2012;Valls-Fox et al 2018). These pans are highly seasonal, and their location strongly constrains animal movement during the dry season (Loarie et al 2009;Valls-Fox et al 2018).…”