Mountain Biking and Trail-Building Destroy Wildlife Habitat!
The major harm that mountain biking does is that it greatly extends the human footprint (distance that one can travel) in wildlife habitat. E-bikes multiply that footprint even more. Neither should be allowed on any unpaved trail. Wildlife, if they are to survive, MUST receive top priority!
What were you thinking??? Mountain biking and trail-building destroy wildlife habitat! Mountain biking is environmentally, socially, and medically destructive! There is no good reason to allow bicycles on any unpaved trail!
Bicycles should not be allowed in any natural area. They are inanimate objects and have no rights. There is also no right to mountain bike. That was settled in federal court in 1996: https://mjvande.info/mtb10.htm . It's dishonest of mountain bikers to say that they don't have access to trails closed to bikes. They have EXACTLY the same access as everyone else -- ON FOOT! Why isn't that good enough for mountain bikers? They are all capable of walking....
Why do mountain bikers always insist on creating illegal trails? It's simple: they ride so fast that they see almost nothing of what they are passing. Therefore, they quickly get bored with any given trail and want another and another, endlessly! (In other words, mountain biking is inherently boring!)
A favorite myth of mountain bikers is that mountain biking is no more harmful to wildlife, people, and the environment than hiking, and that science supports that view. Of course, it's not true. To settle the matter once and for all, I read all of the research they cited, and wrote a review of the research on mountain biking impacts (see https://mjvande.info/scb7.htm ). I found that of the seven studies they cited, (1) all were written by mountain bikers, and (2) in every case, the authors misinterpreted their own data, in order to come to the conclusion that they favored. They also studiously avoided mentioning another scientific study (Wisdom et al) which did not favor mountain biking, and came to the opposite conclusions.
Mountain bikers also love to build new trails - legally or illegally. Of course, trail-building destroys wildlife habitat - not just in the trail bed, but in a wide swath to both sides of the trail! E.g. grizzlies can hear a human from one mile away, and smell us from 5 miles away. Thus, a 10-mile trail represents 100 square miles of destroyed or degraded habitat, that animals are inhibited from using. Mountain biking, trail building, and trail maintenance all increase the number of people in the park, thereby preventing the animals' full use of their habitat. See https://mjvande.info/scb9.htm for details.
Mountain biking accelerates erosion, creates V-shaped ruts, kills small animals and plants on and next to the trail, drives wildlife and other trail users out of the area, and, worst of all, teaches kids that the rough treatment of nature is okay (it's NOT!). What's good about THAT?
To see exactly what harm mountain biking does to the land, watch this 5-minute video: http://vimeo.com/48784297.
The latest craze among mountain bikers is the creation of "pump tracks" (bike parks). They are alleged to teach bicycling skills, but what they actually teach are "skills" (skidding, jumping ("getting air"), racing, etc.) that are appropriate nowhere! If you believe that these "skills" won't be practiced throughout the rest of the park and in all other parks, I have a bridge I'd like to sell you! ...
The common thread among those who want more recreation in our parks is total ignorance about and disinterest in the wildlife whose homes these parks are. Yes, if humans are the only beings that matter, it is simply a conflict among humans (but even then, allowing bikes on trails harms the MAJORITY of park users -- hikers and equestrians -- who can no longer safely and peacefully enjoy their parks).
The parks aren't gymnasiums or racetracks or even human playgrounds. They are WILDLIFE HABITAT, which is precisely why they are attractive to humans. Activities such as mountain biking, that destroy habitat, violate the charter of the parks.
Even kayaking and rafting, which give humans access to the entirety of a water body, prevent the wildlife that live there from making full use of their habitat, and should not be allowed. Of course those who think that only humans matter won't understand what I am talking about -- an indication of the sad state of our culture and educational system.