Little Evidence for the Wild Effect

In recent blog posts, we’ve been investigating the Wild Effect and how we might be able to test whether such a phenomenon exists.  We’ve identified books and movies related to the Pacific Crest Trail, the Appalachian Trail, and the Camino de Santiago.

Now that the Wild Effect has been defined, and the investigation has been structured, let’s see if the numbers of hikers support the existence of the Wild Effect on long distance trails.

Image by Clark Edwards

Image by Clark Edwards

Wild Effect

There is some difficulty gathering the number of thru-hikers who have completed the PCT each year.  Before 2013, the Pacific Crest Trail Association (PCTA) counted the number of permits issued. A single permit could list anywhere between 1 and 8 hikers.  Unfortunately, the number of permits prior to 2013 provides an inaccurate gauge.

The PCTA admits that no one really knows how many hikers finish the PCT each year.  The measures available from the PCTA rely on self-reporting.  Our findings are dependent on the honor system.

The graph of self-reported PCT completions shows fewer hikers in 2013, a year after The Wild (book) was published.  There was a strong increase from 2013 to 2014.  Maybe readers took some time to ponder and plan a trip scheduled for two years after the book was published.  The strongest increase in numbers can be seen from 2011 to 2012, in the time leading up to the book’s publication.

The Wild (movie) was released in 2014.  As you can see in the graph above, there is an increase in PCT completions from 2014 to 2015.  However, the increase from 2013 to 2014 is greater.  Please also note, growth in PCT completions from 2015 to 2016 is relatively flat.

If the graph were shifted a bit, and the bump shown in 2012 were seen in 2013, I would declare, “There it is.  There is the Wild Effect.”

Bryson Bump

Like the PCTA, the Appalachian Trail Conservancy (ATC) relies on self-reported trail completions.  The ATC’s website provides numbers of completed AT hikes for the years 2008 to 2015.  Unfortunately, this date range does not address either potential Bryson Bump (i.e., book publication in 1998 or movie release in 2015).  We’ll have to return to this investigation after the ATC releases the 2016 AT completion numbers.

If you are interested, here are the number of AT completions by year from 2008 to 2015.  The number of section hikes completed each year has been removed to better align these numbers with the number of PCT completions listed above.

Source of Numbers:

Source of Numbers:

The Way

Hiker completion numbers for the Camino de Santiago are available for the years 1985 to 2015.  The movie, The Way, was released in 2010, so we are interested in looking at the trail completions following 2010.

Unfortunately, the only hiker completion numbers available are from  There may be some metrics available in Spanish language online resources, but I didn’t find any.

The number of hikers finishing the Camino de Santiago since 1985 has been ever-increasing.  It is a steady march.  There is not a significant increase in the number of hikers following the release of the movie. 

Holy years, or Jubilee years, are declared in years when St. James’s Day (July 25) falls on a Sunday.  The numbers of hikers in Holy years far outpace the numbers in other years.


In this end, during a review of the number of long distance trail completions, I could not see effects or bumps based on related books or movies.  The increases in PCT completions did not really align with the release of the book or movie.  Unfortunately, the Bryson Bump, while interesting, could not be assessed because the numbers of hikers for relevant years were not available.  Finally, the release of the movie, The Way, did not seem to have an effect on the number of hikers completing the Camino de Santiago.

However, let’s remember how we selected our measurements.  While we could have evaluated a few metrics, we chose to review the number of completed hikes.  There is no way to tell how many people visited the trail, hiked on it for a week or a day or a minute, based on their reading of a book or seeing a movie.  These numbers are not collected, so they cannot be assessed.  The number of completions seem to be the one thing that trail authorities do collect.

Do you agree with this conclusion?  Has a key component been left out of this investigation?  Would you have approached this study differently?