Priorities for the Twenty-first Century
The audubon mission is aptly summarized as
the creation of a culture of conservation and preservation of the earth's
biological diversity through protection of birds and habitat.
On a global scale, one overriding problem
transcends all others -- the pressure arising from the earth's ever increasing
populaton. As a body of knowledge has increased, mankind has developed
and used the capacity to render enormous physical changes to the land surface
of the earth. The oceans have not escaped as the ability to harvest
the bounty of the sea has reached unsustainable levels. Sustainability
-- not taking or using at a rate greater than the rate of replacement --
must be the watchword for all activities which use all forms of natural
resources. In some instances, commercial fishing for example, the
time scale is short, two or three years at most. In others, forestry
for example, the time scale is measured in tens of years, in still others,
use of minerals, oil and gas, for example, the time scale is measured in
thousand of years.
Two issues of truly gobal impact involve the
effects of changing concentrations of carbon dioxide and ozone in the atmosphere.
There is no doubt that carbon dioxide levels have increased steadily since
the industrial revolution began. There is less agreement about both
the cause and the prognosis. It is hard to escape the conclusion that the
burning of fossil uels -- wood, coal and oil -- has been a major contributor
to that increase. However, the fossil fuel resources on the earth are surely
finite, even if more extensive than even the most optimistic projections
of only a few years ago. Eventually, mankind will be forced to use
energy sources which are exxentially non-consumptive as far as the earth
is concerned -- solar, wind, tide and, yes even nuclear energy in some
form. The net production of carbon dioxide from energy productions
will then all but cease. In the meantime, the projections are that
the increase in carbon dioxide levels will reduce the radiative loss of
reflected solor energy -- the "greenhouse" effect -- resulting in an increase
in the average temperature at and near the surface of the earth.
But there are many factors not subject to easy evaluations and projection.
The oceans slowly -- very slowly -- absorb carbon dioxide from the atmosphere
and convert it ot bicarbonates and carbonates, some of which are deposited.
In all probability an increase in the carbon dioxide concentration in the
atmosphere will lead to increased levels of photosynthesis. (Fortunately,
much more photosynthesis is effected by small marine organisms than by
green plants and trees.) Photosynthesis uses solar energy to convert
carbon dioxide and water to carbohydrates and oxygen, thus counterbalancing
the natural activities of all non-photosynthetic organisms and the consumption
of oxygen and the production of carbon dioxide (and energy).
The other global factor involves the ozone
concentrations in the upper atmosphere. Ozone is formed in relatively small
quantities in the upper atmosphere by a series of complex gas-phase chemical
reactions. In the upper levels, ozone serves to filter out the hight
energy ultraviolet component of solar radiation. (At lower levels, ozone
is a particularly irritating air pollutant.) the chlorofluorocarbons (CFCs),
although excellent fluids for refrigeration processes, are chemically very
stable and eventually make their way to the upper atmosphere where they
prevent the normal formation of ozone. Ozone levels in the upper atmosphere
have declined since the mid-eighties when reliable measurements first became
available, and quite probably since the seventies. But unlike the situation
with surface air, small bubbles of which become trapped in the polar ice
caps as they form, enabling a historical record to be constructed from
ice cores drilled in the ice caps, thre is no historical record of the
composition of the upper atmoshere. We simply do not know if there
have historically been small or large variations in stratospheric ozone
The upper level ozone problem is being addressed,
essentially worldwide, by changing to refrigerants other than CFC's. However,
the process will take decades to complete, even after the refrigerants
are no longer in use. But the carbon dioxide issue is less tractable.
It seems likely that the earth will experience some surface warming, which
will increase the melting of the polar ice caps, and thus raise mean sea
level. Given the variables discussed above, there is no consensus on the
likely magnitude of the effect, Certainly, the earth has gone through cooling
(iceages) and heating cycles before, and natural systems have, to a large
extent, adapted. The ranges of many species will shift. the
habitat abailable to some will decrease, to others will increase, and populations
will change accordingly.
Nowhere are populations pressures more apparent
than in the loss of tropical rain forests as land is cleared of trees for
primitive agriculture. This is almost certainly the most significant current
threat to biological diversity as far as non-aquatic species are concerned.
Ironically enough, over a perspective of anything longer than a few years,
the rain forests are probably capable of sustainably producing more as
forests than as agricultural fields which tend to deplete of nutrients
rather quickly. Educating the setlers in these areas will be a challenge.
These tropical rain forests are home year
round to large numbers of species of birds, and also the winter home of
many of the migrant species which breed in North America. For the
species which breed in the northern tier, the population pressures on breeding
habitat are not yet severe. Those breeding further south are not as fortunate.
Man as a land manager tends not to like undergrowth, and to disdain variety.
Monocultures of same age single species plants and trees are not usually
attractive to birds and animals. Undergrowth and brush usually is.
Fragmentation of woodlands is another problem. Forest edges although attactive
to many birds, render them more vulnerable to predators and cowbird parasitism.
the fragments may be just too small in area to sustain a population.
The southern tier of North America is the
winter home to many species. And as the population in the south expands,
the forest ae cut down and fragmented, and much land is consumed into the
concrete jungles of the larger cities. Perhaps equally of concern is the
disappearance of the coastal prairie habitat, as the land is used
from cattle grazing or other agricltural purposes, or is developed. Pressure
on wintering habitat can be just as harmful as pressure on breeding habitat.
Survival through the first winter is the biggest challenge a bird faces
after it successfully fledges. Lack of suitable habitat and pressure
from predators sustained by the byproducts of urban and suburban living
take a high toll on first winter birds.
The birding community has been particularly
successful on the Gulf Coast in acquiring some important coastal habitat
used by the neotropical songbirds and shorebirds at a critical stage of
their migration. Most of these areas are vulnerable to the effects
of tropical stoms and hurricanes and should not be developed in any case.
Balancing recreational use of some areas with the protection of the wildlife
also using them is always a challenge, and not one in which the conservation
cause always prevails.
one of the big issues in the first part of
the century in the southern United States and many other developed areas
is sure to be water. These are large areas of desert and semi-desert that
are on the verge of being developed in response to population pressures.
But the lack of available water makes conventional development impossible.
Ecologically, dams are almost always deleterious, and presssure to remove
them is increasing, especially in the north western United States.
Equally undesirable are the barious forms of river water diversion, for
the health of the areas downstream and the coastal estuaries and bays into
which they flow depends on adequate flow and the occasional flushing action
of higher flows.
Although continued vigilance is certainly
necessary, the severe pollution problems of the twentieth century are already
ameliorated. The case of conservaton is probably not furthred by
extremist demands to remove the last few percent at great economic cost
or lifestyle disruption. Neithr zero risk nor zero pollution are practical,
not technically or economically feasible. There are naturally occurring
"pollutants" everywhere in the enviroment and we must recognize that.
That is not to say that there are not some further improvements, economically
feasible, that can and must be made.
What should be our priorities in creating
a culture of conservation? First and foremost, Audubon should continue
to be a responsible voice of reason and modration. Nationally, we should
consider focusing on sustainability and the population pressures, as clean
air and water are now widely recognized as neccessary goals. On a state-wide
basis, we need to stay on top of the water issues, and promote a conservation-minded
stewardship of the ninety-seven percent of Texas land which is privately
owned. It is at a state level that environmental education must continue
to be promoted. A conservation minded next generation of Texas residents
is essential to continued progress. The coastal plain from the Sabine to
the Rio Grande is inordinately important bird habitat. Also important is
the Rio Grande Valley from the mouth of the river upstream to Falcon Dam
and beyond. Including the areas on the southern side of the river, this
is an economically disadvantaged region of great population pressure, but
also an area of great biological significance. Clearing and fragmentation
of the habitat is already a severe problem, and the population of the region
must be one of the prime targets of environmental education efforts.
Locally, we must continue our efforts. Our
coastal wetlands are still threatened by some in local govrnment whose
ultimate motive still be to drain them. Our coastal bird sanctuaries must
be conserved and managed with the interests of the bird first and foremost.
Restoration of coastal prairie habitat is a desirable goal. Just a little
to our north, restoration of more areas in what was the Big Thicket should
be a priority. Most importantly, adequately wide riparian corridors of
mixed hardwoods and pines should be restored and managed with wildlife
in mind. Additional larger areas, preferably contigous with existing protected,
areas are desirable. But conservation will not happen unless the people
and their leaders support it. The goals, the reasons for them and the methods
to achieve them must be imprinted on future generations. Environmental
education must be the cornerstone of our strategy.
John A. Whittle