Improving ecological connectivity assessment : a step forward to consider connectivity concerns in landscape planning

Abstract

Landscape connectivity has a great impact on some main threats to biodiversity such as habitat fragmentation, land use and climate change, and the expansion of invasive species and diseases. Therefore, connectivity models and measures are increasingly recognized as key tools to guide conservation management and have become a central focus of numerous biodiversity conservation strategies. However, assessing landscape connectivity is a complex process that involves multiple biotic and abiotic factors such as landscape structure and dynamics, species habitat selection, organisms' movement behavior, and dispersal capacity. Most current connectivity models overlook many of these factors, limiting their accuracy and their effectiveness to guide conservation actions. Even though this simplicity was the only plausible or the best choice in terms of data availability and cost-benefit tradeoff until now, recent advances in computing and connectivity modeling allow including other relevant factors to better reflect species movements and guide more effective and successful actions. However, techniques to include these factors are still being developed and their underlying implications are unknown. Both traditional and developing techniques may require different input data, produce different results with unknown accuracy, and lead to different consequences for conservation planning. There is a need for a comprehensive understanding of how these differences influence connectivity modeling and the subsequent effects on conservation planning in order to select the most adequate modeling technique for each connectivity study. perspectivas de este estudio sean de amplio interés y puedan guiar futuros análisis teóricos y sus aplicaciones prácticas. landscape structure (Tischendorf and Fahrig 2000;Taylor et al. 2006). One important step in connectivity modeling dependent on both landscape structure and the focal species requirements is the delimitation of habitat patches (i.e., areas with relatively homogenous environmental conditions of suitable habitat where the focal species could potentially reside and maintain a healthy population) within a heterogenous matrix of non-habitat for the focal species. The spatial arrangement of these habitat patches determines the distance in-between them, which together with the dispersal capacity of the focal species, influences the likelihood of movement between each pair of patches (Urban and Keitt 2001;Saura et al. 2011;Santini et al. 2013). For example, the distance between two habitat patches could be easily traversed by big mammals or birds with high dispersal abilities but be too far away for short dispersers such as insects or small amphibians. Landscape structure and the focal species also influence the quality and amount of resources available in each habitat patch, which in turn affect species' willingness to stay in or migrate from or to each habitat patch and thus landscape connectivity. In fact, some small or low suitable habitat patches might be only useful to some species when com...