May 17, 2001
Whereas:
1. Mountain bikes greatly increase erosion, particularly, creating
narrow ruts that make walking difficult, widening trails, removing top
soil and vegetation, and making trail treads slippery and dangerous;
this is due to their knobby tires, additional weight, and increased
speed, momentum, acceleration, and skidding;
2. They make it much easier for people to get farther into wildlife
habitat and travel farther in the same length of time, thus posing an
increased threat to wildlife;
3. The speed at which they travel makes it more difficult to notice
small animals and plants in the trail and avoid crushing them;
4. Bikes, especially on the narrow trails that mountain bikers prefer,
and at the speeds that many mountain bikers travel, intimidate,
displace, and endanger wildlife and people;
5. Mountain biking is bad role modelling, because children who see
people on mountain bikes learn (non-verbally) that rough treatment of
natural areas is okay;
6. The Park City Agreement with IMBA (International Mountain Biking
Association) was to gain support for Wilderness designation from
mountain bikers; however, IMBA and mountain bikers have been opposing
Wilderness designation because Wilderness by definition is off-limits
to machinery such as bikes. They have instead been lobbying for
"protected" areas to be administered under designations that allow
mountain biking. They are also asking for new wilderness areas to be
"gerrymandered" to exclude trails that they want to remain open to
mountain biking. In addition, the process by which the Park City
Agreement and mountain bike policy were created was undemocratic and
thus violated Club policy: input from Club members opposing the
changes was ignored, and some were even excluded from meetings where
deliberations were conducted!
7. Its support of mountain biking is an embarrassment for the Club,
since it is so obviously an anti-environmental activity, akin to the
use of motorized ORVs.
8. The presence of mountain bikes negatively impacts one's experience
of tranquil nature, because they remind us of the urban environment
and its associated stresses -- exactly what we are trying to escape
from!
Therefore be it resolved that:
The Sierra Club actively oppose the off-road use of bicycles, mountain
boards, and all other off-road vehicles;
The Club eliminate its separate mountain biking policy, and subsume
mountain biking under the ORV policy, as it was before the Park City
Agreement -- in other words, rescind that agreement."
The ideal policy on mountain biking -- one that allows bicyclists
to enjoy their sport, while protecting wildlife and wildlife habitat -
- is that of Yosemite National Park: bicycles are restricted to
pavement. It is highly unusual that a land manager would implement a
policy more protective of wildlife than the Sierra Club's policy, but
there it is! ("Bicycles (including mountain bikes), in-line skates,
scooters, and strollers must remain on paved roads and designated
paved bike paths. They are not allowed on hiking trails or anywhere
off-pavement." See http://www.nps.gov/yose/guide/yguide4.pdf.)
Here are some of the reasons why the Club should rescind the Park
City Accord and the mountain biking policy it produced, and adopt the
Yosemite rule:
For about four million years prior to 1980, human beings felt
themselves capable of enjoying nature without bringing along large
pieces of machinery. With the advent of the mountain bike, many people
now seem incapable of enjoying nature except from the top of a
mountain bike: they claim that banning bikes "excludes" them from the
area. We are literally creating a generation that is too lazy to walk,
and a generation that thinks that the rough treatment of natural areas
is an acceptable activity! It is also impossible to pay much attention
to nature, while having to control a bicycle, often on unfamiliar
trails, at the same time: we are creating a generation that sees
nature purely as a human playground, whose purpose is to provide
"technical singletrack" and other physical challenges.
Since ordinary bicycles can't take the pounding that they would
receive off of pavement, special "mountain" bikes had to be built that
could withstand such punishment. By Newton's laws of physics, the
pounding that the bike receives is identical to the pounding that it
applies to the trail! According to recent statistics from the Sporting
Goods Manufacturers Association, there are approximately 8 million
mountain bikers. That is an enormous beating that we are giving our
precious, scanty remaining wildlife habitat! One look at a mountain
bike is enough to tell you that it is up to no good: the knobby tires
are designed to rip up the soil, and the suspension systems are
designed to insulate the rider from the shocks, as they beat the trail
to a pulp.
While hikers generally step over tree roots, and cross streams by
means of stepping stones, logs, or bridges, bikers usually ride across
the tree roots, ripping off the bark, and ride through the stream bed,
destroying that habitat (see e.g.
http://www.imba.com/resources/science/trail_etiquette.html and
http://home.pacbell.net/mjvande/overview.htm). Most hikers use shoes
with flat soles, leaving the trail practically as they found it.
Bikes, on the other hand, tend to create narrow V-shaped grooves that
are not only difficult or impossible to walk on, but also difficult to
bike on! Therefore, everyone is forced to continually widen the trail.
Thus, allowing bikes on trails greatly increases the need for, and the
cost of, trail maintenance, subjecting wildlife to further human
intrusion. Knobby tires are also designed to rip up the soil,
accelerating erosion. Bikes increase the total weight of the trail
user, as well as the pressure (weight per unit area) on the soil: the
"footprint" of a bike is much smaller than that of a hiker. Bikers
also travel several times as fast as a hiker (increasing the
horizontal forces on the soil), and several times as far (multiplying
their impacts on wildlife and wildlife habitat).
Several "studies" have been produced that claim to show equal
impacts from hikers and bikers. However, even if we accept that
dubious result, what they actually measure is impacts per mile! Thus,
the biker's total impact is still several times that of a hiker,
because they travel so much farther. I have monitored mountain bikers'
newsgroups and email lists for several years. They consistently
advertise their rides as being between 17 and 60 miles per day. My
typical hike is a few miles. I once hiked 15 miles (while
investigating mountain bike damage at Pleasanton Ridge Regional Park),
but at the end, I could barely walk!
In the long run, probably the greatest harm that mountain biking
will do is to vastly increase the human "footprint" in wildlife
habitat. Since bikes have been allowed on trails, the number of people
invading wildlife habitat, the area that they have impacted, the
amount of time that they spend there, as well as the extent of
physical damage, has increased enormously. In some parks, such as
China Camp State Park and Pleasanton Ridge Regional Park in the San
Francisco Bay Area, mountain bikers now far outnumber hikers. Many
mountain bikers have even started biking at night, partly to be able
to bike illegally and not get caught. All of this effectively shrinks
the habitat available to wildlife. It is now possible to visit those
parks and see almost no wild animals!
Mountain biking makes parks very expensive to maintain and
police, drawing resources away from wildlife protection. The only way
for police to catch renegade mountain bikers is with a motorcycle,
which is expensive and further harms the park. There is no practical
way to enforce rules that allow bikes on only some trails. In
addition, bikes carry seeds and spores on their tires, propagating
exotic species long distances. For example, they are suspected of
being a major factor in the transmission of Sudden Oak Death in the
San Francisco Bay Area, California. Mountain bikers also "use up"
parks more quickly: they transit trails so fast that they soon get
bored with them, and start clamoring for more trails to be open to
bikes. It also means that they soon need to drive long distances to
find suitable places to ride. Hikers, who experience every sight,
sound, touch, smell, and sometimes taste as they walk, may never
exhaust the delights of nearby trails. I have hiked some of the same
trails for eighteen years, without ever getting bored with them!