bikers cause the environment.
Basically the study says that hikers cause the same amount of damage to the
environment as mountain bikers and horses are the worst offenders.
http://www.rockymountainnews.com/drmn/sports_columnists/article/0,1299,DRMN_83_5560106,00.html
Reading the article, I was reminded of the statement "In the absence of
truth, we make up stories."
That sure seems to be the case in this emotionally charged issue.