Urban open spaces from a dispersal perspective: lessons from an individual-based model approach to assess the effects of landscape patterns on the viability of wildlife populations

Abstract

Green areas drawn on a city plan represent open spaces that have different meanings for humans and wildlife. Diverse kinds of green may influence species viability in urban environments. It is necessary to understand what those areas mean for wildlife populations and how land-use changes affect habitats and movements for making scientifically defensible planning and design decisions. My objective was to demonstrate how open space and urban development patterns affect the viability of wildlife populations in urbanizing landscapes from a movements perspective. Eight scenarios for 2060 for an urbanizing area near Portland, Oregon combined four open space (none, corridors, parks, and network) with two urban development patterns (compact and dispersed). Dispersal model HexSim simulated three target species – Red-legged frog (Rana aurora aurora), Western meadowlark (Sturnella neclecta) and Douglas squirrel (Tamasciurus douglasii) – movements on those scenarios to compare and contrast sustained populations to the ca. 2010 baseline landscape. Network scenarios presented the largest number of frog breeders. Greenway scenarios showed the largest populations of squirrels. Park and network scenarios sustained viable populations of meadowlarks, but park scenarios performed best. Compact development scenarios performed best for most indicators, while dispersed development scenarios performed better for meadowlarks. Network scenarios performed best when considering the collective of species. Networks presented more diverse habitats, sustaining higher diversity of species. For plans to sustain more species, more comprehensive and diverse habitats must be promoted, otherwise trade-offs should be expected – like the extinction of meadowlarks in greenway scenarios.

The impact of urbanisation on chipmunks, arboreal and flying squirrels: a global systematic review

“…Somewhat similar results were found in another study that investigated how open space and urban development patterns will affect the viability of wildlife populations in urbanising landscapes, taking into account animal movement patterns in the urban matrix (Penteado 2021). Here, simulations were applied using eight scenarios for 2060 for an urbanising area near Portland, Oregon, USA.…”

“…The combinations of four open space (none, corridors, parks and network) with two urban development patterns (compact and dispersed) were modelled, using the same three target species as in the previous study, predicting how the different scenarios would affect movements and, consequently, population size. For Douglas squirrels, the greenway scenarios showed the largest populations and the compact development scenarios performed best for most indicators (Penteado 2021). However, considering all three target species, networks presented the solution with more diverse habitats, sustaining higher species diversity (Penteado 2021).…”

“…For Douglas squirrels, the greenway scenarios showed the largest populations and the compact development scenarios performed best for most indicators (Penteado 2021). However, considering all three target species, networks presented the solution with more diverse habitats, sustaining higher species diversity (Penteado 2021).…”

“…A step further was taken by two studies that used a quantitative approach of predicted landscape change, based on different proposals of key ideas for organising space, often referred to as 'design concepts' or 'concept plans'. These concept plans that link landscape ecology theory to landscape planning are typically used by landscape architects and planners, to develop spatial concepts useful for the creation of open spaces in areas with rapid urbanisation (Penteado 2013(Penteado , 2021. These studies focused on the predicted urban expansion of the city of Damascus, Oregon, USA.…”

HexFire: A Flexible and Accessible Wildfire Simulator

“…HexSim [24] is a well-established software application that has been used in >60 peer-reviewed publications. Although HexSim models have traditionally been designed to conduct population viability analysis for species of conservation concern [25][26][27][28][29][30][31][32][33][34], use of the platform has expanded to a wider range of topics (e.g., disease models [35]). HexSim and HexFire are spatially explicit and can easily incorporate multiple static or dynamic maps quantifying the amounts and patterns of fuels, moisture levels, wind, ignition sites, management interventions, and other drivers relevant to wildfire.…”