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Roads (resistance surface component) - A landscape connectivity analysis for the coastal marten (Martes caurina humboldtensis)

Metadata Updated: February 22, 2025

The resistance surface that formed the basis of our coastal marten connectivity model is comprised of several data layers that represent forested and non-forested land cover, waterbodies, rivers, roads, and serpentine soils.

This dataset contains the roads data used in the resistance surface. To see actual resistance values assigned to the road classes in this raster when the resistance surface is compiled, see the associated spreadsheet of resistance surface data sources and resistance values.

To build the roads resistance layer, we used the OpenStreetMap dataset (OpenStreetMap contributors 2018), which is a global, collaborative project to create a free, editable map of the world’s roads. OpenStreetMap contains 33 different types of roadway in the modeled landscape that are classified based on type, size, usage, etc. (https://wiki.openstreetmap.org/wiki/Map_Features #Highway). We selected 14 of these that seemed likely to have the potential to impact coastal marten habitat and movements, modeling them as having higher resistance with increasing width and the amount and speed of vehicle traffic, as implied in the classification descriptions.

We examined descriptions of the 33 roadway classifications in OpenStreetMap that occurred in our modeled landscape. Because of the origins of this global dataset, most of these road types have been given names more typically used in Great Britain than in the USA (e.g. “Motorway” instead of “Freeway”). However, good descriptions of all classifications were available in supporting documentation online (https://wiki.openstreetmap.org/wiki/Map_Features#Highway), allowing us to assess which categories were likely to impact coastal marten habitat and movements based on road width and the amount and speed of vehicle traffic implied in the classifications (we lacked data on actual traffic levels or speed limits). We assumed that freeways and major divided highways would act as strong “psychological” deterrents to martens crossing them because of the noise and disturbance from traffic and the likelihood of having to cross a wide area with little or no cover (Forman and Alexander 1998, Alexander and Waters 2000). These roads also probably pose the greatest risk of mortality from being struck by a vehicle; we assigned them a resistance value of 150. We then assigned decreasing resistance values through smaller highways and roads (“Trunk”, “Primary”, “Secondary”, and “Tertiary” roads and their associated “link roads”, which are generally very short offshoots connecting to other roads) (Fig. 4D, Table 2 of report). Many of the smallest roads (such as residential roads and logging roads) overlapped with data represented in the OGSI or ESLF layers, which could have led to “double counting” the resistance of these features and modeling them as more significant barriers than we intended them to be. Therefore, we ended up not assigning resistance values to anything smaller than “Unclassified” roads, which are usually two-lane roads connecting to small rural communities. Ultimately, 11 road classifications were assigned resistance values >0 (see Appendix 1 for full list).

Rivers and roads were represented on the resistance surface as linear features a single pixel 30m wide. Because many of these features were modeled as representing significant barriers to movement by martens, we took care to minimize the occurrence of any breaks in these linear features that would encourage LCPs to pass through them. In many instances, roads and rivers are in fact wider than 30m, and in these cases the pixels were classified by the relevant surrounding land cover type (OGSI or ESLF).

This is an abbreviated and incomplete description of the dataset. Please refer to the spatial metadata for a more thorough description of the methods used to produce this dataset, and a discussion of any assumptions or caveats that should be taken into consideration.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

References

https://iris.fws.gov/APPS/ServCat/Reference/Profile/146360
https://www.fws.gov/arcata/shc/marten

Dates

Metadata Created Date June 1, 2023
Metadata Updated Date February 22, 2025

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date February 22, 2025
Publisher U.S. Fish and Wildlife Service
Maintainer
@Id http://datainventory.doi.gov/id/dataset/df09d66c0e5bd94725f7d191fb0b8430
Identifier FWS_ServCat_146360
Data First Published 2020-05-01T12:00:00Z
Data Last Modified 2020-05-01
Category geospatial
Public Access Level public
Bureau Code 010:18
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://datainventory.doi.gov/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Data Quality True
Harvest Object Id 9e3c438f-b022-45be-a28d-f2e8fd5337aa
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Homepage URL https://iris.fws.gov/APPS/ServCat/Reference/Profile/146360
Metadata Type geospatial
Old Spatial -124.58,38.38,-122.06,46.43
Program Code 010:028, 010:094
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Fish and Wildlife Service
Related Documents https://iris.fws.gov/APPS/ServCat/Reference/Profile/146360, https://www.fws.gov/arcata/shc/marten
Source Datajson Identifier True
Source Hash ef9728c506cc8ec28bf95dc8461b67b5428c88d485ef96a67b97f4788eec65df
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -124.58, 38.38, -124.58, 46.43, -122.06, 46.43, -122.06, 38.38, -124.58, 38.38}

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