M
Mike Vandeman
Guest
The Effects of Mountain Biking on Wildlife and People --
Why Off-Road Bicycling Should be Prohibited
Michael J. Vandeman, Ph.D.
May 31, 1997
Mountain biking is a relatively new sport. According to a
mountain biking (MTB) web page (http://www.mtb-bike.com), "The
commercial Mountain Bike evolution didn't start until 1974 and its
first production bikes didn't appear in stores until about 10 years
later". (Lower gearing, fat, knobby tires, sturdier construction,
but particularly the sealed bearing -- which could be ridden in
dirt without getting destroyed -- are what made "mountain" (off-
road) bicycling possible.) Partly for this reason, and partly
because the MTB is, from one point of view, just a special case of
an ORV (off-road vehicle), environmentalists and scientists have
been slow to study and recognize the special threat that the
mountain bike represents to wildlife. Although there are many
studies of ORVs, I am not aware of any solid scientific studies
specifically on MTBs and their effects on wildlife.
To most environmentalists, bicycles have always been the
epitome of good. We are so used to comparing bikes to cars, that it
never occurred to us that the bicycle would be ever used for
anything bad. Indeed, replacing motor vehicles with bicycles
deserves our adoration. But anything can be used for good or evil,
and using bikes to expand human domination of wildlife habitat is
clearly harmful.
Human beings think they own every square inch of the Earth,
and that they therefore have the right to do what they want with
it. This is, of course, absurd. It is also the reason that we are
losing species at an unforgivable rate: we have crowded wildlife
out of its habitat. Even in our parks, where we have vowed to
protect wildlife, it is not protected from hikers, equestrians,
park "managers", firefighters, mountain bikers, airplanes,
helicopters, cars, roads, concessionaires, or biologists. Thus, the
primary reason that mountain bikes are harmful to wildlife is that
they, like other technological aids (cars, skis, rafts, rock-
climbing equipment, etc.), make it much easier for people to get
into wildlife habitat.
(Sadly, most people have forgotten that the only thing that
makes parks worth visiting is the wildlife that live there: it is
_____
precisely the wildlife (and paucity of humans) that make a park a
_________________________________________________________________
park. Without wildlife (i.e., all nonhuman, nondomesticated species
____
-- plants as well as animals), the parks would be boring piles of
bare rock.)
Biology
_______
First and most obvious, mountain bikes kill organisms that
live on and under the soil: "When it comes to pure recreational
destructiveness, ... off-road vehicles (ORVs) far surpass
powerboats. ... It is a rare environment indeed where a vehicle can
be taken off-road without damage. ... Standard ORVs with their
knobby tires are almost ideal devices for smashing plant life and
destroying soil. Even driven with extreme care, a dirt bike will
degrade about an acre of land in a twenty-mile drive. ... Not only
do the ORVs exterminate animals by exterminating plants, they
attack them directly as well. Individual animals on the surface and
in shallow burrows ... are crushed. ... One great problem with ORVs
___________________________
is that they supply easy access to wilderness areas for
_______________________________________________________
unsupervised people who have ... no conception of the damage they
_________________________________________________________________
are doing" (Ehrlich and Ehrlich, pp.169-171; emphasis added).
_________
(Although mountain bikes were hardly known when this was written,
it is obvious that the same applies to them.)
Recently, one of the largest Alameda whipsnakes (a California
threatened species) ever found was killed by a mountain biker in
Black Diamond Mines Regional Preserve near here. Others have been
killed on other East Bay regional parks. Kathryn Phillips in
Tracking the Vanishing Frogs described how ORVs crossing creeks
____________________________
crush toads and their eggs (both buried in the sand). Bikes are
generally ridden too fast to avoid killing small animals.
Obviously, the animals didn't evolve in the presence of mountain
bikes, and can't be expected to deal very effectively with such
quiet, fast-moving objects. Even hikers can kill small animals, if
they aren't careful. The one time I went to look for an Alameda
whipsnake, I almost stepped on one, which was lying in grass
growing in the trail, and didn't move until I had almost stepped on
it.
Soils are extremely complex communities of living organisms.
They sometimes are very fragile and once destroyed take decades to
be recreated (e.g. desert cryptogamic soil). Soil destruction is
hastened by acceleration (braking, speeding up, climbing, and
turning, which apply horizontal forces to the soil), by tire lugs,
which break the surface, and by water, which softens the soil and
makes it easier to demolish.
In the Golden Gate National Recreation Area (GGNRA), "park
officials noted serious erosion problems on certain steep narrow
trails and determined that restricting bicycle use would slow such
erosion. [They] noted that on narrow trails bicyclists passing
other users would either leave the trail or force the other users
off the trail to the detriment of off-trail vegetation and
wildlife. ... Downhill bicycle travel on steep slopes is usually
accompanied by braking and often by skidding which tends to push
dislodged surface gravels into ditches, water bars, and drains.
Heavy bicycle use on steep trails usually requires that these
ditches, water bars, and drains be cleared more frequently than
those used by hikers and equestrians only. ... Park staff and
visitors reported that bicyclists on these ... trails often skidded
to control their speed, slid off of trails on sharp turns, or cut
across off-trail areas at certain 'switch-backs'" (Bicycle Trails
Council of Marin v. Bruce Babbitt).
Mud containing seeds and spores sticks to bike tires, thereby
often carrying species of plants into areas where they had not
existed (becoming "exotics"). This is worsened by the fact that
bicycles travel long distances, and are often carried to distant
locations (sometimes even foreign countries) by motor vehicle. It
is well known that such exotic species can cause havoc when
introduced into new habitats.
Most of us were raised to believe that "non-consumptive"
recreation is harmless to wildlife. We are taught to enjoy
ourselves in nature, guilt-free, as long as we don't directly harm
wildlife. However, recent research, and the huge scale of current
recreation activities, have discredited this idea. "Traditionally,
observing, feeding, and photographing wildlife were considered to
be 'nonconsumptive' activities because removal of animals from
their natural habitats did not occur.... nonconsumptive wildlife
recreation was considered relatively benign in terms of its effects
on wildlife; today, however, there is a growing recognition that
wildlife-viewing recreation can have serious negative impacts on
wildlife" (Knight & Gutzwiller, p.257).
In other words, the mere presence of people is often harmful
________
to wildlife, and the more, the worse. "The notion that recreation
has no environmental impacts is no longer tenable. Recreationists
often degrade the land, water, and wildlife resources that support
their activities by simplifying plant communities, increasing
animal mortality, displacing and disturbing wildlife, and
distributing refuse" (ibid, p.3) "Recreational disturbance has
traditionally been viewed as most detrimental to wildlife during
the breeding season. Recently, it has become apparent that
disturbance outside of the animal's breeding season may have
equally severe effects" (p.73) "People have an impact on wildlife
habitat and all that depends on it, no matter what the activity"
(p.157); "Perhaps the major way that people have influenced
wildlife populations is through encroachment into wildlife areas"
(p.160). "Outdoor recreation has been recognized as an important
factor that can reduce biosphere sustainability.... Indeed,
recreational activities, including many that may seem innocuous,
can alter vertebrate behaviour, reproduction, distributions, and
habitats" (p.169).
Knight & Gutzwiller's book contains numerous specific examples
of how these negative effects are created. We may not know what the
organisms are thinking, but the effect is that they die, are forced
to expend extra energy that may be in short supply, become more
susceptible to predation, or are forced to move to less suitable
habitat, losing access to preferred foods, mates, nesting sites,
etc. Since most of us live safely in the midst of plenty, it is
hard for us to understand wildlife's predicament. We are flexible
enough to survive almost anywhere; they are not. Often they have no
other place to live. None of the existing "studies" on mountain
biking evaluate its effects on wildlife. They are usually concerned
only with visible effects on the trail. In Tilden Regional Park,
there are three separate, heavily used mountain biking trails
through the middle of supposedly protected Alameda whipsnake
habitat areas!
"Displaced animals are forced out of familiar habitat and must
then survive and reproduce in areas where they are not familiar
with the locations of food, shelter, and other vital resources....
Hammitt and Cole ... ranked displacement as being more detrimental
to wildlife than harassment or recreation-induced habitat
changes.... Densities ... of 13 breeding bird species were
negatively associated with the intensity of recreation activity by
park visitors, primarily pedestrians and cyclists" (ibid, pp.173-
4); "off-road vehicles can collapse burrows of desert mammals and
reptiles" (p.176).
Sociology
_________
Hikers, especially the elderly, have been abandoning their
favorite trails, due to bikers that scare them, hit them, harass
them, and destroy the serenity of the parks. Parks are supposed to
be a refuge from the crush of humanity and the noise, danger, and
artificiality of urban areas. Why bring to our parks the very
_______________________________
things that most people go there to escape?! There is absolutely
____________________________________________
nothing wrong with bicycling, in its proper setting (on a road). It
is a wonderfully healthful activity. But wildlife is already in
_______
danger due to loss of habitat (worldwide, one quarter of all
animals are threatend with extinction, according to the IUCN
(International Union for the Conservation of Nature and Natural
Resources)). It can't afford to lose any more. And people have very
similar needs for being in nature. Our elderly are like wildlife,
in that they have nowhere else to go for the experience of nature
that they are accustomed to.
By definition, hiking trails are the minimum size necessary
for a person to hike (approx. 18 inches wide), since they are
supposed to have a minimal impact on the environment. They aren't
wide enough for a bicyclist to safely pass a hiker or another
bicyclist. Mixing bikers and hikers is dangerous for both. In fact,
mountain biking is also dangerous for lone riders, since hiking
trails don't follow a predictable pattern and have very short sight
distances (the distance that one can see ahead on the trail).
Emergency room doctors report that a large percentage of mountain
bikers incur serious accidents.
"The record includes hundreds of letters from park users
recounting stories of collisions or near misses with speeding or
reckless bicyclists on all kinds of trails but particularly on
steep and narrow trails. Hikers and bird watchers repeatedly told
how they have been forced off of trails by speeding bicycles and
how they have had their peace and solitude on the trails
interrupted by bicycles that -- because they are quiet and fast --
seemed to appear out of nowhere and be immediately upon the hikers
and other users. Equestrians told how their horses have been
startled by speeding or oncoming bicycles and have become restless,
on several occasions even throwing and injuring experienced riders.
Though most users admitted that the great majority of bicyclists
were polite and safety-conscious, letters from hikers, equestrians,
bird watchers, joggers, and other users also repeatedly recounted
incidents of rudeness, threats, and altercations when they have
complained to an offending bicyclist about dangerous conduct. Park
staff also reported having received such complaints. ... NPS's
[National Park Service's] finding that user conflict and visitor
danger would be reduced by limiting bicycle trail access in GGNRA
was supported by ample evidence. ... Notwithstanding the
responsible user, bicycles are often perceived by other users as a
disruptive influence on park trails. Although most of the few
reported bicycle accidents in the park involve only single
individuals, letters and reports from hikers and equestrians tell
of many close calls and confrontational and unsettling
experiences". "No single-track trails [in the Marin Headlands] were
found suitable for bicycle use" (Bicycle Trails Council v. Bruce
Babbitt).
Since bicycles require wider trails, parks now often use
bulldozers to create and maintain those trails, vastly increasing
their impacts. In Claremont Canyon Regional Preserve in Oakland,
California, a new trail was created by means of a "small" (6 foot
blade) bulldozer. But it rolled off the trail and had to be rescued
by a much bigger bulldozer. The existence of bicyclists on trails
also forces park rangers to police the trails using motor vehicles
(cars or motorcycles), since it is the only way they can hope to
catch them! This also increases negative impacts on wildlife.
Children learn mostly nonverbally (by watching adults and
other children). Mountain biking is bad role modeling for them,
since it teaches them that human domination and destruction of
wildlife habitat is normal and acceptable.
Mountain bikers like to claim that excluding them from trails
constitutes "discrimination". They say that other user groups
(hikers and equestrians) receive better treatment from land
managers. There is no basis for such a claim, since all users are
subject to exactly the same rules. For example, on a trail closed
to bikes, everyone is allowed on the trail -- only the bikes are
________ _____
excluded! In spite of what they claim, mountain bikers have never
______
been excluded from any trail! Even if my way of "enjoying" the
wilderness is to race my bulldozer there, I am not allowed to do
that. And this is not because land managers like hikers more than
bulldozer racers. I am not being excluded from the wilderness; I
can go there whenever I want, as long as I don't try to bring my
__________________________________
Why Off-Road Bicycling Should be Prohibited
Michael J. Vandeman, Ph.D.
May 31, 1997
Mountain biking is a relatively new sport. According to a
mountain biking (MTB) web page (http://www.mtb-bike.com), "The
commercial Mountain Bike evolution didn't start until 1974 and its
first production bikes didn't appear in stores until about 10 years
later". (Lower gearing, fat, knobby tires, sturdier construction,
but particularly the sealed bearing -- which could be ridden in
dirt without getting destroyed -- are what made "mountain" (off-
road) bicycling possible.) Partly for this reason, and partly
because the MTB is, from one point of view, just a special case of
an ORV (off-road vehicle), environmentalists and scientists have
been slow to study and recognize the special threat that the
mountain bike represents to wildlife. Although there are many
studies of ORVs, I am not aware of any solid scientific studies
specifically on MTBs and their effects on wildlife.
To most environmentalists, bicycles have always been the
epitome of good. We are so used to comparing bikes to cars, that it
never occurred to us that the bicycle would be ever used for
anything bad. Indeed, replacing motor vehicles with bicycles
deserves our adoration. But anything can be used for good or evil,
and using bikes to expand human domination of wildlife habitat is
clearly harmful.
Human beings think they own every square inch of the Earth,
and that they therefore have the right to do what they want with
it. This is, of course, absurd. It is also the reason that we are
losing species at an unforgivable rate: we have crowded wildlife
out of its habitat. Even in our parks, where we have vowed to
protect wildlife, it is not protected from hikers, equestrians,
park "managers", firefighters, mountain bikers, airplanes,
helicopters, cars, roads, concessionaires, or biologists. Thus, the
primary reason that mountain bikes are harmful to wildlife is that
they, like other technological aids (cars, skis, rafts, rock-
climbing equipment, etc.), make it much easier for people to get
into wildlife habitat.
(Sadly, most people have forgotten that the only thing that
makes parks worth visiting is the wildlife that live there: it is
_____
precisely the wildlife (and paucity of humans) that make a park a
_________________________________________________________________
park. Without wildlife (i.e., all nonhuman, nondomesticated species
____
-- plants as well as animals), the parks would be boring piles of
bare rock.)
Biology
_______
First and most obvious, mountain bikes kill organisms that
live on and under the soil: "When it comes to pure recreational
destructiveness, ... off-road vehicles (ORVs) far surpass
powerboats. ... It is a rare environment indeed where a vehicle can
be taken off-road without damage. ... Standard ORVs with their
knobby tires are almost ideal devices for smashing plant life and
destroying soil. Even driven with extreme care, a dirt bike will
degrade about an acre of land in a twenty-mile drive. ... Not only
do the ORVs exterminate animals by exterminating plants, they
attack them directly as well. Individual animals on the surface and
in shallow burrows ... are crushed. ... One great problem with ORVs
___________________________
is that they supply easy access to wilderness areas for
_______________________________________________________
unsupervised people who have ... no conception of the damage they
_________________________________________________________________
are doing" (Ehrlich and Ehrlich, pp.169-171; emphasis added).
_________
(Although mountain bikes were hardly known when this was written,
it is obvious that the same applies to them.)
Recently, one of the largest Alameda whipsnakes (a California
threatened species) ever found was killed by a mountain biker in
Black Diamond Mines Regional Preserve near here. Others have been
killed on other East Bay regional parks. Kathryn Phillips in
Tracking the Vanishing Frogs described how ORVs crossing creeks
____________________________
crush toads and their eggs (both buried in the sand). Bikes are
generally ridden too fast to avoid killing small animals.
Obviously, the animals didn't evolve in the presence of mountain
bikes, and can't be expected to deal very effectively with such
quiet, fast-moving objects. Even hikers can kill small animals, if
they aren't careful. The one time I went to look for an Alameda
whipsnake, I almost stepped on one, which was lying in grass
growing in the trail, and didn't move until I had almost stepped on
it.
Soils are extremely complex communities of living organisms.
They sometimes are very fragile and once destroyed take decades to
be recreated (e.g. desert cryptogamic soil). Soil destruction is
hastened by acceleration (braking, speeding up, climbing, and
turning, which apply horizontal forces to the soil), by tire lugs,
which break the surface, and by water, which softens the soil and
makes it easier to demolish.
In the Golden Gate National Recreation Area (GGNRA), "park
officials noted serious erosion problems on certain steep narrow
trails and determined that restricting bicycle use would slow such
erosion. [They] noted that on narrow trails bicyclists passing
other users would either leave the trail or force the other users
off the trail to the detriment of off-trail vegetation and
wildlife. ... Downhill bicycle travel on steep slopes is usually
accompanied by braking and often by skidding which tends to push
dislodged surface gravels into ditches, water bars, and drains.
Heavy bicycle use on steep trails usually requires that these
ditches, water bars, and drains be cleared more frequently than
those used by hikers and equestrians only. ... Park staff and
visitors reported that bicyclists on these ... trails often skidded
to control their speed, slid off of trails on sharp turns, or cut
across off-trail areas at certain 'switch-backs'" (Bicycle Trails
Council of Marin v. Bruce Babbitt).
Mud containing seeds and spores sticks to bike tires, thereby
often carrying species of plants into areas where they had not
existed (becoming "exotics"). This is worsened by the fact that
bicycles travel long distances, and are often carried to distant
locations (sometimes even foreign countries) by motor vehicle. It
is well known that such exotic species can cause havoc when
introduced into new habitats.
Most of us were raised to believe that "non-consumptive"
recreation is harmless to wildlife. We are taught to enjoy
ourselves in nature, guilt-free, as long as we don't directly harm
wildlife. However, recent research, and the huge scale of current
recreation activities, have discredited this idea. "Traditionally,
observing, feeding, and photographing wildlife were considered to
be 'nonconsumptive' activities because removal of animals from
their natural habitats did not occur.... nonconsumptive wildlife
recreation was considered relatively benign in terms of its effects
on wildlife; today, however, there is a growing recognition that
wildlife-viewing recreation can have serious negative impacts on
wildlife" (Knight & Gutzwiller, p.257).
In other words, the mere presence of people is often harmful
________
to wildlife, and the more, the worse. "The notion that recreation
has no environmental impacts is no longer tenable. Recreationists
often degrade the land, water, and wildlife resources that support
their activities by simplifying plant communities, increasing
animal mortality, displacing and disturbing wildlife, and
distributing refuse" (ibid, p.3) "Recreational disturbance has
traditionally been viewed as most detrimental to wildlife during
the breeding season. Recently, it has become apparent that
disturbance outside of the animal's breeding season may have
equally severe effects" (p.73) "People have an impact on wildlife
habitat and all that depends on it, no matter what the activity"
(p.157); "Perhaps the major way that people have influenced
wildlife populations is through encroachment into wildlife areas"
(p.160). "Outdoor recreation has been recognized as an important
factor that can reduce biosphere sustainability.... Indeed,
recreational activities, including many that may seem innocuous,
can alter vertebrate behaviour, reproduction, distributions, and
habitats" (p.169).
Knight & Gutzwiller's book contains numerous specific examples
of how these negative effects are created. We may not know what the
organisms are thinking, but the effect is that they die, are forced
to expend extra energy that may be in short supply, become more
susceptible to predation, or are forced to move to less suitable
habitat, losing access to preferred foods, mates, nesting sites,
etc. Since most of us live safely in the midst of plenty, it is
hard for us to understand wildlife's predicament. We are flexible
enough to survive almost anywhere; they are not. Often they have no
other place to live. None of the existing "studies" on mountain
biking evaluate its effects on wildlife. They are usually concerned
only with visible effects on the trail. In Tilden Regional Park,
there are three separate, heavily used mountain biking trails
through the middle of supposedly protected Alameda whipsnake
habitat areas!
"Displaced animals are forced out of familiar habitat and must
then survive and reproduce in areas where they are not familiar
with the locations of food, shelter, and other vital resources....
Hammitt and Cole ... ranked displacement as being more detrimental
to wildlife than harassment or recreation-induced habitat
changes.... Densities ... of 13 breeding bird species were
negatively associated with the intensity of recreation activity by
park visitors, primarily pedestrians and cyclists" (ibid, pp.173-
4); "off-road vehicles can collapse burrows of desert mammals and
reptiles" (p.176).
Sociology
_________
Hikers, especially the elderly, have been abandoning their
favorite trails, due to bikers that scare them, hit them, harass
them, and destroy the serenity of the parks. Parks are supposed to
be a refuge from the crush of humanity and the noise, danger, and
artificiality of urban areas. Why bring to our parks the very
_______________________________
things that most people go there to escape?! There is absolutely
____________________________________________
nothing wrong with bicycling, in its proper setting (on a road). It
is a wonderfully healthful activity. But wildlife is already in
_______
danger due to loss of habitat (worldwide, one quarter of all
animals are threatend with extinction, according to the IUCN
(International Union for the Conservation of Nature and Natural
Resources)). It can't afford to lose any more. And people have very
similar needs for being in nature. Our elderly are like wildlife,
in that they have nowhere else to go for the experience of nature
that they are accustomed to.
By definition, hiking trails are the minimum size necessary
for a person to hike (approx. 18 inches wide), since they are
supposed to have a minimal impact on the environment. They aren't
wide enough for a bicyclist to safely pass a hiker or another
bicyclist. Mixing bikers and hikers is dangerous for both. In fact,
mountain biking is also dangerous for lone riders, since hiking
trails don't follow a predictable pattern and have very short sight
distances (the distance that one can see ahead on the trail).
Emergency room doctors report that a large percentage of mountain
bikers incur serious accidents.
"The record includes hundreds of letters from park users
recounting stories of collisions or near misses with speeding or
reckless bicyclists on all kinds of trails but particularly on
steep and narrow trails. Hikers and bird watchers repeatedly told
how they have been forced off of trails by speeding bicycles and
how they have had their peace and solitude on the trails
interrupted by bicycles that -- because they are quiet and fast --
seemed to appear out of nowhere and be immediately upon the hikers
and other users. Equestrians told how their horses have been
startled by speeding or oncoming bicycles and have become restless,
on several occasions even throwing and injuring experienced riders.
Though most users admitted that the great majority of bicyclists
were polite and safety-conscious, letters from hikers, equestrians,
bird watchers, joggers, and other users also repeatedly recounted
incidents of rudeness, threats, and altercations when they have
complained to an offending bicyclist about dangerous conduct. Park
staff also reported having received such complaints. ... NPS's
[National Park Service's] finding that user conflict and visitor
danger would be reduced by limiting bicycle trail access in GGNRA
was supported by ample evidence. ... Notwithstanding the
responsible user, bicycles are often perceived by other users as a
disruptive influence on park trails. Although most of the few
reported bicycle accidents in the park involve only single
individuals, letters and reports from hikers and equestrians tell
of many close calls and confrontational and unsettling
experiences". "No single-track trails [in the Marin Headlands] were
found suitable for bicycle use" (Bicycle Trails Council v. Bruce
Babbitt).
Since bicycles require wider trails, parks now often use
bulldozers to create and maintain those trails, vastly increasing
their impacts. In Claremont Canyon Regional Preserve in Oakland,
California, a new trail was created by means of a "small" (6 foot
blade) bulldozer. But it rolled off the trail and had to be rescued
by a much bigger bulldozer. The existence of bicyclists on trails
also forces park rangers to police the trails using motor vehicles
(cars or motorcycles), since it is the only way they can hope to
catch them! This also increases negative impacts on wildlife.
Children learn mostly nonverbally (by watching adults and
other children). Mountain biking is bad role modeling for them,
since it teaches them that human domination and destruction of
wildlife habitat is normal and acceptable.
Mountain bikers like to claim that excluding them from trails
constitutes "discrimination". They say that other user groups
(hikers and equestrians) receive better treatment from land
managers. There is no basis for such a claim, since all users are
subject to exactly the same rules. For example, on a trail closed
to bikes, everyone is allowed on the trail -- only the bikes are
________ _____
excluded! In spite of what they claim, mountain bikers have never
______
been excluded from any trail! Even if my way of "enjoying" the
wilderness is to race my bulldozer there, I am not allowed to do
that. And this is not because land managers like hikers more than
bulldozer racers. I am not being excluded from the wilderness; I
can go there whenever I want, as long as I don't try to bring my
__________________________________
