Hierarchical patch delineation in fragmented landscapes

Purpose

We developed a tool, FragPatch (FP), to delineate habitat patches for highly fragmented landscapes from a user-defined suitability map and two landscape perception values for a species of interest.

Methods

We wrote a Python script in ArcGIS to delineate habitat patch networks using the user inputs and ArcGIS tools such as Euclidean distance, focal maximum, and reclassify. We validated the tool from mapped locations of urban deer and classified imagery for Syracuse, New York, USA.

Results

FP successfully delineated salient patch networks and functional connectivity for white-tailed deer (Odocoileus virginianus borealis) in our fragmented study area, and complements a similar tool, PatchMorph (PM), developed for rural landscape with more uniform land cover.

Conclusions

A trade-off exists when choosing to use FP or PM and the decision must rely upon a well-defined research question. FP is better suited for isolating patches of habitat when the surrounding matrix is of low quality and suitable areas are highly scattered on the landscape. PM is able to identify patches when the matrix is more uniform, and is better at identifying broader scale connectivity than FP. We expect species biologists and urban landscape planners to use FP to better define patch networks and to understand the implications of fragmentation on a range of species population concerns, including conflicts with human uses.