I see that the latest statistics on the number of visitors to National Parks has come out, but I cannot find any reference to how a visitor is determined.
For instance, there is a section of the Blue Ridge Parkway in Asheville that is used heavily by local commuters to get from one area of town to another. Is each car travelling here a visit? Similarly, driving through the Great Smokey Mountains National Park is one way to get from an area in North Carolina to Tennessee and vice versa. Does it count as a visitor if one is merely using the roadway?
If have frequently hiked into and out of the Smokies or Shenandoah Park by trail. How is my visit counted? Does a large vehicle visiting the Park carrying multiple people create multiple visits, or just one?
I am guessing that the number of visitors is counted based on estimates using a small bit of data. If so, how accurate is it?
Caught a podcast recently that addressed part of this question. IIRC, the Park Service makes certain assumptions about the number of people in each vehicle and that assumption varies depending on the day of the week to account for likely commuters vs. visitors, etc. Great Smoky Mountain National Park also recently added a parking permit requirement that should better account for actual visitors vs. passers through.
Having worked in another national park service with a similar range of properties from vast acreages surrounded by farms and more wildness to small single lot properties in towns, it will be a combination of:
ticket sales - online and entry booths [and private tour operators will be required to provide their numbers]
sample surveys with vehicle and head counts
vehicle trip counters across entry routes
more general surveys of community use.
Accurate numbers are important to demonstrate that a core mission of park conservation is being achieved - in allowing people to access and experience natural and cultural heritage, that investments in visitor infrastructure, museums and interpretation are justified [esp. when there is never enough funding and each dollar is fought over], but also to make sure that there is not over-use, and through that lose the value of the visitor experience . No better way to lose the wilderness / back country sense of remoteness than to run into 40 other people each day, at least 10 of them acting like jerks.
Thanks for the answers folks. It would be interesting to see the sample size of the data in the estimation of total park use and to see what actually constitutes a visit — or even a breakdown of what these park visitors do. I suspect more people get out of their cars and walk in Yellowstone, say, than in the Smokies because it may take much more of an effort for people to get to parks in less populated areas.