Effects of mis-alignment between dispersal traits and landscape structure on dispersal success in fragmented landscapes

Abstract

Dispersal is fundamental to population dynamics and hence extinction risk. The dispersal success of animals depends on the biophysical structure of their environments and their biological traits; however, comparatively little is known about how evolutionary trade-offs among suites of biological traits affect dispersal potential. We developed a spatially explicit agent-based simulation model to evaluate the influence of trade-offs among a suite of biological traits on the dispersal success of vagile animals in fragmented landscapes. We specifically chose traits known to influence dispersal success: speed of movement, perceptual range, risk of predation, need to forage during dispersal, and amount of suitable habitat required for successful settlement in a patch. Using the metric of relative dispersal success rate, we assessed how the costs and benefits of evolutionary investment in these biological traits varied with landscape structure. In heterogeneous environments with low habitat availability and scattered habitat patches, individuals with more equal allocation across the trait spectrum dispersed most successfully. Our analyses suggest that the dispersal success of animals in heterogeneous environments is highly dependent on hierarchical interactions between trait trade-offs and the geometric configurations of the habitat patches in the landscapes through which they disperse. In an applied sense, our results indicate potential for ecological mis-alignment between species' evolved suites of dispersal-related traits and altered environmental conditions as a result of rapid global change. In many cases identifying the processes that shape patterns of animal dispersal, and the consequences of abiotic changes for these processes, will require consideration of complex relationships among a range of organism-specific and environmental factors.

The Importance of Forest-Nonforest Transition Zones for Avian Conservation in a Vegetation Disturbance Gradient in the Northern Neotropics

“…TRA provided habitat for common species that favor open secondary forest (Rutt et al., 2019), forest edge with cattle pasture, and primary forest due to shared vegetation structure and composition qualities relative to PRES and DIS. The common species of PRES and DIS with high mobility find resources at sections of TRA that are adjacent to PRES and DIS (Atkins et al., 2019). However, TRA did not have higher overall species diversity relative to PRES and DIS.…”

Anthropogenic disturbance drives dispersal syndromes, demography, and gene flow in amphibian populations

“…, Atkins et al. ). Overall, these studies have reported reduced dispersal propensity or capacity in fragmented landscapes, which is usually attributed to prohibitive costs during the transition phase across the matrix (Cheptou et al.…”

Body size and life history shape the historical biogeography of tetrapods

“…Different life history traits may therefore be related to successful dispersal in both processes, and mixing both continental and oceanic barriers can obscure life history–dispersal relationships. Biogeographic dispersal may hence be context dependent (depending on the type of barrier and possibly their characteristics, that is, environmental harshness and degree of landscape fragmentation, as has been shown for active, short-distance dispersal previously 29 , 30 ). Future work should therefore aim to consider different types of barriers separately (which is not possible in the present study due to computational constraints; Methods and Supplementary Information Section 2 ).…”

“…For instance, in some clades, large species with an extreme life history strategy were better dispersers (for example, Chamaeleonidae and Corvidae), and in other clades species with fast life history strategies but small body sizes were better dispersers (for example, Cricetidae and Dasyuridae). Multiple traits may therefore interact in their influence on biogeographic dispersal 33 , and this influence may be mediated by the environment and/or biotic interactions 29 , 30 .…”