Why are Cows on the Preserves?
Many of our members
wonder if we should be having cows running around on the McKenzie Preserve, the
Tivy Mountain Preserve, and parts of the Miller Preserve on Black Mountain. It's
a valid question, and the answer may surprise you. The cows are there to help us
save the native plants and animals which live on the preserves. This is not only
counterintuitive but goes against decades of adverse publicity that cows and
cattlemen have received from the environmental community. The simple truth is
that conservation land managers and researchers have found that anywhere
non-native grasses thrive, grazing is essential for preserving many of our
native wildflowers, small vertebrates such as kangaroo rats and lizards, and
invertebrates such as bugs and butterflies.
Many years ago when
organizations like The Nature Conservancy and agencies like the California
Department of Fish and Game began buying land for the protection of native
species, most of the lands were being grazed. The people charged with managing
these conservation lands thought that since the land looked so good with cattle
on it, removing the cattle would make it even better. What at the time seemed
reasonable decisions turned out in almost every case to be disastrous for the
resources that were being protected. On preserve after preserve, existing
populations of wildflowers, small mammals and even butterflies declined or
disappeared. When The Nature Conservancy realized this, it experimented with
returning grazing to the preserves and the declines were reversed. With
hindsight the explanation is obvious.
What are here now that
were not here in California in 1600 are a great many aggressive non-native
annual grasses that evolved in climates similar to California's. These grasses
came accidentally, first with the Spaniards and later with the forty-niners.
Within a few years these alien species had spread from one end of the state to
the other with devastating consequences for the native grasses and wildflowers.
The invasion was so fast that we have few descriptions of pre-European
conditions. Biologists now feel that the San Joaquin Valley was much more like
the desert than like the vast grasslands that were once thought to be the case.
Native bunch grasses and shrubs were interspersed with open ground where small
vertebrates could run about catching prey and escaping predators. These open
spaces were where the annual wildflowers grew and were used by butterflies and
other insects.
In contrast, the
non-native annual grasses formed dense mats that covered every inch of the
ground. Three valley biologists (Germano, Rathburn and Saslaw) with extensive
experience with native species said in a paper published last year that
"many plants and animals native to this area are adapted to relatively open
habitats and therefore are morphologically, behaviorally, and physiologically
ill-equipped to live in dense grass." Fortunately, the livestock our
European ancestors brought with them provided a partial solution to the problem.
Grazing kept the grasses in check and allowed some natives to survive. It seems
now that without cows and sheep, the extinction of native plants and animals
would have been much greater in California valleys and foothills.
For a time conservation
land managers thought that fire could be used to control alien grasses. It is
true that for a year or two after a moderate fire the increase in natives can be
spectacular. Unfortunately, the effect lasts only two or three years. Then you
have to burn again. In the Millerton area there are some 20,000 acres of land
owned by state and federal agencies and the Sierra Foothill Conservancy. If we
were to use a four year fire schedule, we would have to burn 5000 acres per
year. Does anyone believe the Valley Air Pollution Control Board would permit
that? Also, there are no studies that I am aware of that show what the effect,
good or bad, of repeated burning of foothill lands might be. Doing burns is
expensive and requires a lot of machinery and highly trained personnel.
Disasters with huge economic and human consequences can happen when mistakes are
made and controlled burns get away like the one in Los Alamos two years ago.
Some friends of mine lost their home in that fire and were only able to move
into their rebuilt home this Christmas.
In addition to its
ecological benefits, grazing pays its own way. SFC's income from grazing is only
a small part of our total budget, but it helps to pay for the maintenance of the
preserves. We could do without it and it does not provide the motivation for
grazing, but it is welcome.
It goes without saying that overgrazing can have a devastating effect on
habitat. What we have tried to do on the preserves is to learn from others like
The Nature Conservancy who have done a great many studies on the subject. We are
also participating in two grazing studies on the McKenzie Preserve that will
help guide our grazing policy in the future. What we believe we have learned so
far is that the keys are timing and numbers. That is why the cattle are not on
the preserve all year long. Our leases also control the number of cattle. An
interesting thing we are learning is that "best grazing practices" for
cattlemen are very similar to 'best grazing practices" for wildlife. SFC is
also fortunate to be working with three very good cattlemen, Steve McDonald,
Tucker Slender and Mike Urrutia as lessees. I have learned a great deal from
these gentlemen about the land, and that all wisdom about the land does not
reside in the environmental community that I have been a part of for so many
years.
One of SFC's goals is
to preserve the native flora and fauna of the foothills. Grazing is an essential
tool for doing that job, and it will be a lot easier to do if we form alliances
with the cattle people.
Chuck Peck
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