The goal of this lab was to use various geoprocessing tools in order to utilize to perform vector analysis in ArcGIS. For this particular lab I was put in the scenario that I was to help the DNR develop a map showing suitable habitat for bears in Marquette County, Michigan.
Background
To start this lab I was given a number of GPS data points which showed recent bear locations within the study area of Marquette County, MI. I also was given a number of parameters which I needed to take into consideration when developing a map of suitable habitat. These included: stream proximity, land cover type and distance from urban/built-up areas. Another big issue to consider was to make sure that my proposed area was within the DNR management zones which was data also given to me.
Methods
The first step in this process was to develop the land cover types which most typically contain bears. Using the bear location data and the land cover data I was given, I spatially joined the feature classes. Once they were joined together I summarized the land cover feature in order to determine how many bears (based on the location data) were found in each habitat/ land cover type. From the summary I learned that most bears were found in either mixed forest land, forested wetland or evergreen forest land. I then exported these three particular land cover types as the bear_land_cover feature class.
Next, I needed to determine how many of the bears were found near streams to see if they typically were or were not located near these features. To do this I used the select by location tool to select the bears from the location data which are within 500 meters of a stream. After I did this I found that 49 of the 68 bear locations (72.06%) met these parameters. Based on this value of 72%, I was able to conclude that streams are of high importance when determining bear habit since biologists would consider a feature such as this important if the value was greater than 30%.
The other important factor that the DNR requires consideration of when working to produce a potential habitat for these bears is whether the areas are within the DNR's management zone. The DNR only has certain zones in which they can set up management areas so it is important to take this into consideration when I develop a final proposal. In order to get the zones ready to analyze I clipped out any of the zones outside of the study area.
To produce my final proposed bear habitat regions I had to take into consideration the following characteristics: must be within either mixed forest lands, forested wetlands or evergreen forest land, must be within 500 meters of a stream and must be within the DNR management area. The first step was to buffer the streams at 500 meters and intersect these three features to come up with a potential habitat for the bears. However, another factor I need to take into consideration is the proximity these areas have to urban/built-up areas. It is best to keep the bear management lands at least 5 kilometers from any urban areas. After exporting the urban/built-up land class from the overall land cover data I buffered it by 5 kilometers. Next I used the erase tool to eliminate all of the possible bear habitat within 5 kilometers of any urban areas. Once this was done I was left with a final proposed habitat (or in my data model, final_output).
Results
The final map that I produced as a result of the last model can be seen below. This map clearly shows both the potential bear habitat within this region of Marquette County, MI and the areas where I would propose there should be habitat. The proposed habitat is within 500 meters of a stream, within the DNR management zones, at least 5 kilometers from urban/built-up land and located in either mixed forest lands, forested wetlands or evergreen forest land. While there are still some bears which are located in the north-west region of the study area there is no proposed habitat there because overall there is very little DNR management zones in that region of the study area. It would be good based on the lack of DNR management in a part of the study area where so many bears have been found to possibly expand the management zones to better protect more bear habitat. The pink, "potential habitat" includes the proposed habitat as it is the habitat before taking into consideration the proximity to urban/built up land. Based on the results from this lab I would propose that the regions shaded in green are the best regions where bear management zones should be in this portion of Marquette County.
USGS NLCD:
http://www.mcgi.state.mi.us/mgdl/nlcd/metadata/nlcdshp.html
Michigan DNR:
http://www.dnr.state.mi.us/spatialdatalibrary/metadata/wildlife_mgmt_units.htm
http://www.mcgi.state.mi.us/mgdl/framework/metadata/Marquette.html
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