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Collect and Map Data About Elk
Use geographic data to understand migration patterns maps
Elk play an essential role in the Greater Yellowstone ecosystem. To better understand the dangers they face, both natural and human-made, National Geographic Explorer Arthur Middleton wanted to know more about the migration patterns of Yellowstone’s elk herds. Why do they migrate? How much time are elk spending on protected lands versus private lands? What can be done to better protect elk migration routes?
Greater Yellowstone ecosystem- Yellowstone National Park and surrounding area
To answer those questions, Middleton first needed to understand where elk were migrating. By compiling a database of animal tracks, both from other researchers and by putting his own GPS collars on elk, Middleton was able to track the routes that herds took across Yellowstone National Park and nearby areas.
GPS collars work by recording and storing x,y coordinates, which then can be mapped to show where the animal has traveled and when. Animal tracks can then be compared to other geographical data, like landcover type, land ownership or administration, temperature and snowmelt, and more. The combination of animal tracks and other data helps researchers understand why the elk migrated and when they were most likely to encounter predators, like wolves, or other dangers, like humans.
What Middleton found was that elk migration was driven primarily by food. Elk graze on grasses and prefer the green shoots that grow after the snow melts in the spring. To find these new shoots, they follow grassy areas from valleys in the winter to mountains in the summer and reverse the trip in the fall.
1) On the toolbar, click Map layers to see the symbols for each herd.
The elk herds are symbolized to show migratory paths during two seasons, spring and fall.
2) On the map, zoom in and explore where the three elk herds migrate.
Do the elk tend to take different migration paths depending on the season?
Once Middleton had collected enough animal tracks, he compared them to other geographical data (landcover type, land ownership, temperature and snowmelt, and more) to understand why the elk migrated and when they were most likely to encounter predators or other dangers.
3) In the Map layers pane, use the Swipe and Transparency tools to compare the elk migration tracks to underlying data, like USA Federal Lands, American Indian Reservations, Populated Places, and roads.
Which herd likely spends the most time in close proximity to humans?
Thinking Geographically
Consider the following questions:
What kinds of challenges do you think elk face as they migrate?