Desert ecosystems in the huge spaces between
the wet places vary greatly in biological value.
Some of the hyper-arid deserts support little life of
any kind, except after rare rainstorms when they
are briefly visited by species from surrounding,
better-watered deserts. One can travel for hours
in parts of southern Libya, Algeria or Peru, eastern
Saudi Arabia and central Oman, northern Sudan,
Chad, Niger, or northern Chile without seeing a
blade of grass or a bush. A daily lizard or gazelle,
or at some seasons a migrating bird, comes as a
surprise. Some authorities have asked, are they
ecosystems at all? Are the connections between
species durable enough to class them as fullyinteractive
systems? (Moore 1978). It is more
debatable whether these wildernesses deserve
the scarce resources available to conservationists.
Perhaps conservationists should concentrate
their efforts on the desert's edge, that is, on arid
ecosystems interposed between the hyper-arid
wildernesses and the savannahs and grasslands.
It is in these areas where the harvesting of wild
products often offers a valuable economic alternative (Box 5.6), and more generally, where
many species have great biological value and are
under maximum threat.
Indiscriminate hunting is one of the biggest threats
to desert biological sustainability, so damaging that
if allowed, it would soon eliminate its own raison
d'être. Hunting may have eliminated the postglacial
mega-fauna of North America, and much
later, North Africa and southwest Asia lost most of
their large mammals to hunters in Roman times.
It is said that on the day on which the Emperor
Titus inaugurated the Roman Coliseum, 5 000 wild
animals were slaughtered. The more distant African
and Asian deserts lost their large mammals after
guns became available in colonial times, when
they were also infected with the European hunting
ethos (Anderson and Grove 1987). In desert Central
Asia, the native Przewalski's horse (Equus caballus
przewalskii), was hunted to extinction in the wild
by about 1870. Hunting and competition with
domestic camels has reduced the population of
the wild Bactrian camel (Camelus bactrianus ferus).
Przewalski's gazelle (Procapra przewalskii) is now
isolated to only four local populations around the
Qinghai Lake in desert China (Li and Jiang 2002).
Hunting continues. Income from trophy hunting in
Namibia was estimated in 2003 to be 14 per cent of
all tourist earnings (Humavindu and Barnes 2003).
Large convoys of air conditioned caravans follow
hunters across the deserts of Arabia, Sudan and
Kazakhstan. The remaining populations of large
mammals, such as various species of gazelle, oryx
(Oryx beisa), addax (Addax nasomaculatus), Arabian
tahr (Hemitragus jayakari) and the Barbary sheep
(Ammotragus lervia) are on the brink of extinction.
Game bird populations are declining fast, particularly
that of the Houbara (Chlamydotis undulata
macqueenii), which is the choice for hunters with
falcons in Arabia and Kazakhstan (Tourenq and
others 2005). Most of these endangered species
need urgent protection: captive breeding (of oryx
as in Oman); reintroduction; restrictive legislation
and its enforcement; and so on. Surprisingly (to
some) help is coming from the hunters, at least as
concerns the Houbara; they have supported captive
breeding, radio tracking and other conservation
measures in Saudi Arabia and the United Arab
Emirates (Bailey and others 1998).
Another threat to dry ecosystems may come
from pastoralists, but here the argument is not so
simple. Pastoralists do indeed use the high nutritive
value of arid grasslands in wet seasons. The Fulani
in Niger take their cattle to the edge of the desert
in the wet season, specifically for this (Penning
de Vries and Djeteyé 1982), as do the Kabbabish
camel nomads in Sudan (Wilson 1978).
The argument about the damage that grazing
might be doing to these ecosystems is unfinished.
Some authorities believe that overstocking has
removed valuable species, and reduced grazing
value. Their evidence includes the replacement of
palatable by unpalatable species, particularly the
woody shrubs that have invaded many arid areas,
as in Arizona (Guo 2004) or in southern Africa
(Wiegand and others 2005). Further evidence lies in
research into recovery times after intense grazing.
In one case, full grass cover only replaced woody
scrubland after 20 years of protection (Valone and
others 2002). Estimates of recovery times for the
Mojave ecosystems range from 50 to 300 years,
but in some cases could reach 3 000 years (Lovich
and Bainbridge 1999).
The counter-argument depends on the model of
these ecosystems as "pulse-response" (see Chapter
1). In seasonal or multi-annual dry periods, the
ecosystem is said to be incapable of supporting
enough stock to do it any damage in the brief,
wet pulses. Only if stock is fed supplements
brought in from wetter areas, or is moved back
and forth from wet to dry areas (which, it is true,
are common practices), is "overgrazing" even
possible. Nomadism, this school also argues, is an
ideal system for using the patchy effect of rainfall
on grazing. Further, especially in the Old World, the
character of many arid ecosystems depends on
grazing, and because some of the native grazing
animals have become domesticated, grazing by
them could be vital in maintaining the original
ecosystem dynamics. Conservation may then
depend more on the choice of grazing intensity and
grazing species, than their total exclusion. Finally,
some authorities believe that overgrazing is much
less of threat in arid climates where forage dynamics
are primarily driven by climatic cycles, than in semiarid
or sub-humid climates where grazing is more likely to be the chief control on the availability of
forage (Briske and others 2003).
Another issue in the conservation of these systems
is the choice of priority. If a rare species has priority,
like the long-lived desert tortoise in the arid Mojave
(Gopherus agassizii, a federally-listed, threatened
species), complete protection from hunters and
graziers may be imperative. If the objective is the
conservation of an ecosystem as a whole, there is
more room for manoeuvre, but there are problems
there too. If there are functioning patches of different
size, all the way from micro-ecosystems sheltered
by bushes or trees, to patches of many hundreds
of square kilometres, what is the optimum size of
protected areas to ensure conservation? The failsafe
rule is: as large as possible.
A more practical question is also exercising
conservationists: should conservation be "expertled"
or "community-based"? (Berkes 2004).
Community-based conservation does not always
succeed, mainly because development and
conservation goals usually conflict, and because the
phrase has become too loosely used. But with care,
the idea of community conservation should resonate
in deserts where people and their grazing animals
have been part of the ecosystem for thousands of
years, and where there is huge wealth of indigenous
knowledge, as Triulzi (2001) describes in Syria.
The beauty of deserts, so essential to tourists and
residents, is a further priority for conservation. There
are at least three conflicting desert aesthetics: desert
as wilderness, as challenge, or as scenery. The
wilderness-seekers - stereotypically, backpackers,
and the well-educated - use deserts to find their
"intellectual humility" (Leopold 1949). To them,
development and the numbers of visitors need
stringent control. The challenge-seekers need
technology to achieve their aims (they might be SUV
drivers). They want to drive over exciting terrain and
may compromise with, even welcome, development.
Given the openness of many deserts and their
accessibility to motor transport, their activity can
be intrusive (Sax 1980). The tourist aesthetic is
subdivided many more times: the Wissa Wassef
romanticism of the image on the title page of this
chapter; the desert fathers (Box 5.2) and/or romantic
decay; Marlboro County; walkabout; T.E. Lawrence;
Rudolf Valentino; and so on. And tastes change.
These various demands need to be balanced with
the needs of people who live and work in the desert,
let alone with the demands of people beyond the
desert for water or energy. The task is not impossible.
Most visitors to the Grand Canyon or Uluru are
impressed by the sensitivity with which they are
managed under the onslaught of tens of thousands
of people in a season, even if a minority complains
one way or another. An advantage of some deserts
over many other global environments is that they are
remarkably resilient. Sand dunes loose the tracks of
people or vehicles after a gentle breeze. Bare rock
may not register a moderate number of footfalls.
But the desert is not everywhere so unforgiving;
there are many places where the demands clash, or
where trampling, littering, and disturbance do lasting
damage. Vehicle tracks in many deserts are visible on
satellite images; they may persist for very many years
(Belnap and Warren 2002).
All forms of conservation (particularly of biological
value and beauty) are best met with some degree
of statutory protection, backed by adequate
funds. The trajectory of the total desert area under
protection is upward, which is encouraging, but
it would need to be accompanied by less easily
monitored trajectories of community involvement,
visitor satisfaction, biological change and funding, to
confirm it as a wholly good story.