Mapping huckleberries in Glacier National Park and the surrounding areas- the grand finale!
Well folks, this is kind of the main reason I launched this project. A solid basemap of some of the most important grizzly bear food sources is integral information to have for all sorts of reasons; bear safety, human safety, bear population, bear habitat use, etc. A previous attempt to map huckleberries in the area that was published in early 2019 by a couple colleagues and myself was a tantalizing first step toward achieving at least some level of fine scale bear food knowledge. You can find it here. Our big takeaway from the previous study was that we could map huckleberries across a vast landscape (with two different methods), but we could only do so with fair-moderate agreement where there were few trees. Our overall accuracies were 75%/79% and our kappas were 0.26/0.31.
This is where we pick up the current project- I wanted to use new methods to improve on our previous mapping effort and hopefully increase our ability to accurately predict where huckleberries are located across the ecosystem. If you've been following along, I used a similar method to the one I used to map juniper in my previous lab note. The basics are as follows- I used an object-based classification of NAIP imagery to map huckleberries using approximately 5000 polygons of non-huckleberry vegetation and 600 polygons of huckleberry vegetation. I fed 70% of those samples into a random forest model and used the remaining 30% to test how well we did.
So, how did we do?! Yes, all of us- you guys made this work possible. Well, we did really, really well. Assuming our proportions of samples are relatively close to reality based on previous work (~10-12% huckleberry), we have an overall accuracy of nearly 96% and a kappa of 0.73- it's an amazing map (still room for future improvement, of course) that is good enough that Chelsea and I now use it as input to plan short family hikes to entertain the kids. "Is there anything less than 5 miles and 1000' elevation with huckleberries galore...".
If there's anybody brave enough to hike the Loop trail down from the Highline on these 90 degree days-
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