April 6, 1998

Supervisor Gavin Newsom

401 Van Ness Avenue

San Francisco, CA 94102

Re: Jet Skis in San Francisco Waters

Dear Supervisor Newsom:

Human beings think that we own, and have the right to dominate, every square inch of the Earth. That, besides being an absurd idea, is the basic reason why we are losing, worldwide, about 100 species per day. Habitat loss is at the top of every list of the primary reasons why species have become extinct or are in danger of becoming extinct.

Outright destruction of habitat (for example, paving it or turning it into farms, golf courses, housing developments, or parks) is not the only way that an area can become untenable (useless) as habitat. Anything that makes it unattractive or unavailable to a given species causes habitat loss. Have you ever wondered why most animals run away when we come near? It certainly isn't because they love having us around! Many animals simply will not tolerate the presence of humans.

Humans are the ants at every other species' picnic. One of the first things that children learn about wild animals is that most of them run (fly, swim, slither, hop) away whenever we get close to them. (A few, such as mosquitoes, like having us around.) Some are more tolerant of us than others, but in any given area, there are at least some that don't like having us around.

Let's take as a premise that we do not want to cause any extinctions. I think that most people agree with that. But what follows, is that we have to set aside adequate habitat for all existing species, and that much of it must be human-free.

What scientific evidence do we have that wildlife need to be free of human intrusion? There is recent research (e.g. Knight and Gutzwiller, 1995) showing that recreation, even activity traditionally thought of as harmless to wildlife, can be harmful, or even deadly: "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" (p. 257). "Activities [involving] nonmotorized travel ... [have] caused the creation of more ... trails in wildlands.... These activities are extensive in nature and have the ability to disrupt wildlife in many ways, particularly by displacing animals from an area" (p. 56). "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). "Recreationists are, ironically, destroying the very thing they love: the blooming buzzing confusion of nature.... The recreation industry deserves to be listed on the same page with interests that are cutting the last of the old-growth forests, washing fertile topsoils into the sea, and pouring billions of tons of greenhouse gases into the atmosphere" (p.340).

Of course, no humans set out to drive wildlife (that is, all non-human, non-domesticated species) to extinction. We are simply trying to have a good time. Nature is attractive to us, and we love to experience it close up. The problem is that, as Aldo Leopold predicted, we are "loving the wilderness to death" (Roderick Nash, quoted in Taylor, p.93).

The major factor facilitating this invasion of wildlife habitat is technology: oil, machines, cars, trucks, ORVs, mountain bikes, boats, rafts, skis, and recently, snow mobiles, mountain boards, and jet skis.

In order to protect our scanty remaining wildlife, there are two possible approaches: ban people, or make it harder for them to get into wildlife habitat by banning their technological aids. The first is expensive, management-intensive, and repugnant in a free society. The best, cheapest, most humane way to protect wildlife is to ban the use of technologies that make wildlife habitat easy to access.

Cliff faces were relatively safe havens for birds, until the invention and widespread use of climbing gear. Wild river channels contained many inaccessible spots, until the advent of modern rafts. Most parts of the desert would see few if any human visitors, if it weren't for roads and ORVs. Cross-country skis and snowmobiles make the winter time no longer safe for the wildlife that are active then. And jet skis now make lakes, rivers, and marine shallows more accessible than ever before. To launch a jet ski into the shallow waters that are so important to marine wildlife takes little money, little training, and little energy. Jet skis put our most vulnerable marine and avian wildlife directly into the hands of some of our most biologically ignorant and least responsible citizens.

It is easy for us to forget that wildlife don't own refrigerators full of food. Many wildlife live on very tight "budgets" of food and energy, and cannot afford to be disturbed. Too much disturbance can lead to unsuccessful reproduction or even starvation. Birds frightened off the nest can lose the eggs or young to predators. Toxic pollutants emitted by jet skis hurt and kill wildlife and their food sources. And, of course, jet skis are a physical danger and annoyance to people, as well, including their operators.

There is absolutely no reason to allow the use of jet skis, anywhere or any time. Humans have managed to live comfortable, enjoyable, satisfying lives for some 400,000 years without the benefit of the jet ski. And San Francisco will be fine, too!

Sincerely yours,

Michael J. Vandeman, Ph.D.


Ehrlich, Paul R. and Ehrlich, Anne H., Extinction: The Causes and Consequences of the Disappearances of Species. New York: Random House, 1981.

Knight, Richard L. and Kevin J. Gutzwiller, eds. Wildlife and Recreationists. Covelo, California: Island Press, c.1995.

Life on the Edge. A Guide to California's Endangered Natural Resources: Wildlife. Santa Cruz, California: BioSystem Books, 1994.

Myers, Norman, ed., Gaia: An Atlas of Planet Management, Garden City, NY: Anchor Books, 1984.

Noss, Reed F. and Allen Y. Cooperrider, Saving Nature's Legacy: Protecting and Restoring Biodiversity. Island Press, Covelo, California, 1994.

Taylor, Paul W., Respect for Nature. Princeton, NJ: Princeton University Press, 1986.

Vandeman, Michael J., http://www.imaja.com/change/environment/mvarticles/, especially "Wildlife and the Ecocity" and "'Harmless' Recreation Kills Wildlife!"

Ward, Peter Douglas, The End of Evolution: On Mass Extinctions and the Preservation of Biodiversity. New York: Bantam Books, 1994.

Wilson, Edward O., The Diversity of Life. Cambridge, Massachusetts: Harvard University Press, 1992.