Data from: Habitat suitability and connectivity modeling reveal priority areas for Indiana bat (Myotis sodalis) conservation in a complex habitat mosaic
Cable, Ashleigh et al. (2020), Data from: Habitat suitability and connectivity modeling reveal priority areas for Indiana bat (Myotis sodalis) conservation in a complex habitat mosaic, Dryad, Dataset, https://doi.org/10.5061/dryad.jm63xsj7d
Conservation for the Indiana bat (Myotis sodalis), a federally endangered species in the United States of America, is typically focused on local maternity sites; however, the species is a regional migrant, interacting with the environment at multiple spatial scales. Hierarchical levels of management may be necessary, but we have limited knowledge of landscape-level ecology, distribution, and connectivity of suitable areas in complex landscapes.
We sought to 1) identify factors influencing M. sodalis maternity colony distribution in a mosaic landscape, 2) map suitable maternity habitat, and 3) quantify connectivity importance of patches.
Using 3 decades of occurrence data, we tested a priori, hypothesis-driven habitat suitability models. We mapped suitable areas and quantified connectivity importance of habitat patches with probabilistic habitat availability metrics.
Factors improving landscape-scale suitability included limited agriculture, more forest cover, forest edge, proximity to medium-sized water bodies, lower elevations, and limited urban development. Areas closer to hibernacula and rivers were suitable. Binary maps showed that thirty percent of the study area was suitable for M. sodalis and 29% was important for connectivity. Most suitable patches were important for intra-patch connectivity and far fewer contributed to inter-patch connectivity.
While simple models may be effective for small, homogenous landscapes, complex models are needed to explain habitat suitability in large, mixed landscapes. Suitability modeling identified factors that made sites attractive as maternity areas. Connectivity analysis improved our understanding of important areas for bats, identified suitable patches that may be isolated from the habitat network, and prioritized areas to target restoration.
Land cover environmental data (e.g., total area of forest in 500-m radius) were derived from the "Land cover of Illinois 1999-2000" (IDNR 1999). The original dataset was resampled from 30-m to 100-m resolution. The classes were simplified into major (forest, water, urban, agriculture, grassland, and other) and minor classes (bottomland forest, coniferous forest, and deciduous forest). Total area, total edge, and the number of patches were computed in FRAGSTATS using moving window analyses (100-m, 500-m, and 1-km window sizes).
Distance to water was calculated in ArcMap 10.6.1 (ESRI) using the water area shape files from the National Hydrography Dataset (USGS 2018). Distance to major roads was calculated using the Illinois Department of Transportation road data (IDOT 2017). We calculated the distance from roads that receive an average daily traffic rate of >2 cars/minute.
Original data citations:
Illinois Department of Natural Resources, Illinois Natural History Survey, Illinois State Geological Survey, Illinois Department of Agriculture, United States Department of Agriculture National Agricultural Statistics Service (1999) 1:100,000 Scale. Land Cover of Illinois 1999-2000, Raster Digital Data, Version 2.0, September 2003 https://clearinghouse.isgs.illinois.edu/data/land-cover/land-cover-illinois-1999-2000-data Accessed 4 October 2018
Illinois Department of Transportation (2018) Illinois roads, shape file data https://apps.dot.illinois.gov/gist2/ Accessed 4 October 2018
U.S. Geological Survey (2018) National hydrography dataset https://www.usgs.gov/core-science-systems/ngp/national-hydrography/national-hydrography-dataset?qt-science_support_page_related_con=0#qt-science_support_page_related_con Accessed 4 October 2018
We created suitability maps by modeling Myotis sodalis maternity habitat in MaxEnt. We binarized models based on the 10% suitability threshold in our training occurrence data. We used the Raster to Shapefile tool in ArcMap 10.6.1 to generate the suitable areas shapefile.
We calculated patch importance for habitat connectivity for each suitable area polygon in Conefor Sensinode 2.6. The isolated suitable areas shapefile represents suitable areas that are only important for intra-patch connectivity and not inter-patch connectivity. These methods are explained in detail in "Habitat suitability and connectivity modeling reveal priority areas for Indiana bat (Myotis sodalis) conservation in a complex habitat mosaic."
We created the priority restoration areas shapefile by buffering Myotis sodalis hibernation sites by 125 meters and buffering suitable habitat patches by 10.1 km. We intersected the two buffers to create the layer. Myotis sodalis occurrence locations cannot be shared due to federal restrictions.
ta = total area
te = total edge
np = number of patches
dist = distance to a feature
100 = 100-m radius
500 = 500-m radius
1 = 1-km radius
for = forest
wat = water
bot/bottomland = bottomland forest
conif = coniferous forest
ccd = closed-canopy deciduous forest
ag = agriculture
urb = urban
(e.g., ta_for_100 is total area of forest in a 100-m radius; np_wat_1 is number of water patches in a 1-km radius)
null is a raster with values 1-100 randomly distributed across the landscape
100-m x 100-m cells
3415 columns, 6190 rows
Suitable_areas are polygons that are suitable as determined by our MaxEnt habitat suitability models
Conefor_patch_metrics is a table of the connectivity importance values for each suitable patch. One could join the table to the shapefile for visualization.
Isolated_suit_areas are polygons that are only important for intra-patch connectivity, thus are more isolated from the Myotis sodalis maternity habitat network
Priority_restoration_areas are areas that are within 125 km from a known hibernaculum and also within 10.1 km of a suitable area for Myotis sodalis
Illinois Department of Natural Resources Wildlife Restoration Grant, Award: W-194-R-1