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Sécheresse 2006 ; 17 (1-2) : 195-9
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Grazing, overgrazing and conservation:
Changing concepts and practices
in the Negev rangelands
Linda Olsvig-Whittaker1
Eliezer Frankenberg1
Avi Perevolotsky2
Eugene D. Ungar2
1
Science and Conservation Division, Israel
Nature and National parks Protection
Authority,
3, Am Ve Olamo Street,
Givat Shaul,
Jerusalem 95463
Israel
<[email protected]>
<[email protected]>
<[email protected]>
2
Department of Agronomy and Natural
Resources,
Institute of Plant Sciences,
Volcani Center,
P.O. Box 6,
Bet Dagan 50250
Israel
<[email protected]>
<[email protected]>
Abstract
This review of land use in the Negev, from the perspective of rangeland and nature
conservation, challenges the prevalent concept that Bedouin pastoralism has a purely
negative impact on the conservation of the semidesert landscape in the Negev. We
review more than a century of rangeland research in the Negev and compare it with
current research results. We discuss the general conservation status of the Negev,
including current pastoral customs and the reintroduction of native herbivores, and
our general assessment is that although development poses a real threat to conservation of the Negev, the current level of pastoralism is not likely to result in loss of plant
species. It is more likely that the decline of pastoralism with changing Bedouin
practices will result in shrub invasion and loss of plant species.
Key words: Negev, Israel, rangelands, pastoralism, desert.
Résumé
Pâturage, surpâturage et conservation : changer les concepts et les pratiques dans les
parcours du Negev
Ce texte passe en revue l’utilisation des terres au Negev dans la perspective des
parcours et de la conservation de la nature. Il conteste le concept dominant que le
pastoralisme bédouin a un impact purement négatif sur la conservation des paysages
semi-désertiques du Negev. On examine plus d’un siècle de recherches sur les
parcours du Negev en les comparant aux résultats actuels. Le statut général de la
conservation dans la zone, y compris les coutumes actuelles et la réintroduction
d’herbivores autochtones, sont discutés. Selon notre évaluation générale, bien que le
développement actuel constitue une menace réelle pour la conservation du Negev, le
niveau actuel du pastoralisme ne provoquera sans doute pas la perte d’espèces
végétales. Il est au contraire plus probable que le déclin éventuel du pastoralisme
avec l’évolution des pratiques bédouines provoquera l’invasion d’arbustes et l’élimination de certaines espèces végétales.
Mots clés : Negev, Israël, parcours, pastoralisme, désert.
Introduction,
review of early concepts
Two benchmark books, a century apart,
strongly influenced modern perceptions of
the impact of nomadic pastoralism on the
Sécheresse vol. 17, n° 1-2, janvier-juin 2006
Negev: The Desert of the Exodus by Palmer in 1871 [1] and The Negev, the
Challenge of a Desert by Evenari et al. in
1982 [2]. In this matter, Evenari’s group
quotes Palmer without reservation: “Wherever (the Bedouin) goes, he brings with
him ruin, violence and neglect.... half the
195
0
50 km
Phytogeographic zones
Mediterranean
Irano - Turanian
Saharo Arabian
Sudanic
Jerusalem
Geographic regions
tribal for pasture [9]. Livestock were fattailed Awassi sheep and small Bedouin
black goats, highly adapted for extremely
arid conditions [10]. Grazing was mostly
confined to the distance walked in one day
from a camp (around 5km), with the most
intensive grazing near the camp. During
the last 3,000 years the carrying capacity
per hectare has stood at about 16 head of
sheep and/or goats, for a total of
100,000 head in the Negev [7, 11]. This
long period of stable land use was probably due to the ability to switch between
rangeland grazing and agriculture, and to
move out of the system in times of severe
drought [7] (for an early example, see
Genesis 46: 1-6).
Negev
900
800
Haifa
0
33°
00
80
Arava
500
10
N
0
60
400
0
erran
ean S
7 00
0
60 0
50
ea
600
Medit
70
300
Tel Aviv
200
600
Figure 1. Map of phytogeographic and desert regions in Israel (from [6]).
32°
Jerusalem
32°
100
60
0
500
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35°
Judean Desert
196
south. Oases are a prominent feature
around the Dead Sea.
The Negev comprises two sections:
– the southern Negev is a desert belonging to the Saharo-Arabian region; it receives less than 100mm of rain per year
(figure 2); vegetation is sparse and grazing is usually light;
– the northern Negev, the focus of this
paper, is a semidesert area receiving 100
to 250mm of rain per year, and is an
extension of the Asiatic steppe belt. Vegetation is mostly Irano-Turanian and is considerably affected by human activity (grazing, cultivation, cutting, etc.). Small
livestock herding and grain farming have
been practised here continuously since the
Chalcolithic period (5000 BCE), and the
balance has shifted between these two
activities and between sedentary and
nomadic occupation throughout the history of the Negev [7, 8].
Traditionally, there was no irrigation or
supplementation of food or water for livestock; cereals were used for subsistence or
were exported. Land ownership was in
private parcels for agricultural crops and
400
300
Be’er Sheva
200
31°
Nizzana
100
Sede
Boqer
31°
Hatzeva
Avdat
Mitzpe
Ramon
30°
30°
Eilat
0
25
50 km
35°
desert owes its existence to him and many
fertile plains... have become a parched
and barren wilderness.” This was the prevalent view of most rangeland scientists for
most of the last half century of work in the
Negev [3, 4]. In our note, we will trace the
history of this idea and will lay the basis
for challenging it.
The arid regions of Israel comprise three
deserts (figure 1): the Judean Desert, the
Negev, and the Arava. These are distinct areas, geologically and biologically. The Arava (a dry extension of the
Great African Rift, connecting the Dead
Sea and the Red Sea) comprises mostly
highly saline sands and loess, with subsurface water that enables the growth of
Acacia stands among sparse vegetation
[5, 6]. The flora is mostly Saharo-Arabian,
and the climate is very hot. The Judean
Desert, also distributed along the Rift Valley, extends along the west flank of the
Jordan River and along the Dead Sea, and
is dominated by Irano-Turanian steppe
and desert on limestone hills and marl in
the north, and more rugged terrain with
more Saharo-Arabian elements in the
Figure 2. Average annual precipitation (mm)
map as prepared by the Israel Meteorological
Service in 1990.
Shading in increments of 200mm; AERC research
stations consist of Nizzana, Sede Boqer, Avdat, and
Hatzeva.
Sécheresse vol. 17, n° 1-2, janvier-juin 2006
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Changing land use
Recent decades have seen major changes
in land ownership and patterns of pastoralism. Only a few of the Bedouin have
decided to continue to base the livelihood
of their families on pastoralism; most of the
others have become wage earners. For the
latter group small flocks are more of a
“hobby” to keep the traditions alive than a
livelihood, and only the larger flocks are
economically viable. Food and water are
supplemented, enabling grazing to continue for longer periods of time (or continuously) and in locations in which it was
formerly limited by lack of water. Thus, the
numbers of small livestock are increasing
despite the land use limitations imposed
on pastoralists.
The first census of domesticated animals in
Israel was made by the British mandatory
government in 1930, and it counted only
57,000 sheep and 41,000 goats in the
Negev. These numbers remained more or
less the same after the establishment of the
State of Israel in 1948 and the introduction
in 1950 of the law to protect vegetation
from goat damage, and in the 1970s of
the regulations prohibiting grazing in
nature reserves and other nonagricultural
areas, unless a permit is issued. Since the
1970s, the number of small livestock has
increased to 120,000 in 1995 and
180,000 in 20051. The number of flocks
has declined but their size has increased
[12]. At the same time, contraction of
communal rangelands has restricted
nomadic herding patterns [13]. These
changes have intensified the grazing pressure on the remaining rangeland.
Bedouin sheep husbandry, prevalent in the
region for centuries, is well adapted to the
following phenological cycle. The herds
graze the green, communal rangeland
quite heavily from January or February to
May. The summer (June to September) is a
period of transhumance, during which the
herds graze on contracted stubble fields
and agricultural aftermath. During the fall
and early winter (October to January) the
sheep return to the rangeland and graze
the dry vegetation, drawing most of their
nutritional requirements from supplemented feeds such as maize and barley grains
[12]. A third of the animals migrate to the
north in summer.
Changing concepts
and recent experiments
The changing land use patterns and intensified grazing pressure in some areas height-
ened the need for an evaluation of grazing
impacts in the Negev. At the same time,
recent international comparisons have
indicated that there is a qualitative difference between the Old and the New World
in resilience to grazing [14]. According to
this view, systems with millennia of grazing history (such as the Negev) are more
robust when subjected to traditional patterns of heavy pastoralism [15].
Recent experiments on grazing impact
were conducted at the Bedouin Demonstration Farm (an LTER2 site [16] at Lehavim,
some 15km north of Be’er Sheva, in the
northern Negev), an active research site
since the 1980s. Here, traditional pastoralism was practised under controlled conditions by a single permanent homestead
with sole grazing rights, in an effort to
explore and demonstrate sustainable,
sedentary pastoralism and its impact on
the environment. Since the establishment
of this site in the late 1980s, it was observed that shrub cover slowly increased. The
productivity of the herbaceous vegetation
varied primarily according to habitat and
changes in climatic conditions; no longterm trends in productivity have been
detected (analysis of productivity data of
1990-2003). It seems that the herbaceous
vegetation is well adapted to unpredictable rainfall and high grazing intensity.
Interestingly, grazing exclosures tended to
exhibit enhanced shrub cover at the
expense of herbaceous vegetation, supporting the claim that grazing is not the
cause of “shrub desertification” (the loss of
rangeland by invasion of inedible shrubs)
butisameansofcontrollingshrubencroachment [17, and unpublished data]. The
principal shrub that takes over the habitat
is dwarf prickly burnet (Sarcopoterium spinosum), which has proved quite resistant
to aggressive treatments such as mechanical removal, prescribed burning and, to a
lesser extent, 2,4-D spraying [18].
A study of the grazing impact on the
herbaceous community in Lehavim has
revealed that the diversity of annual plants
is determined by the interaction between
grazing and small-scale spatial and temporal variation in primary productivity [19].
In the more productive habitats (wadis)
grazing is indispensable to the maintenance of high diversity, mainly because
large species dominate the community
when grazing is excluded [20].
Similar research on Bedouin pastoralism
in sandy areas of the Negev supports
these observations [21]: comparison of
vegetation across different soil textures
and grazing intensities showed that species composition and species richness
1
Israel Lands Authority, personal communication.
Sécheresse vol. 17, n° 1-2, janvier-juin 2006
2
LTER: long-term ecological research.
remained unaffected until grazing intensity
reached very high levels, but that they
were relatively strongly affected by changes in soil texture. The authors speculate
that less-resistant species were probably
eliminated millennia ago, and that the
current landscapes are to some extent
adapted to grazing stress.
Grazing and conservation
The current ecological understanding of
the Negev rangeland suggests that two
principal processes would occur following
the exclusion of grazing: an increase in
shrub cover, and a decrease in diversity of
the herbaceous community, in which rare,
small species would be overwhelmed in
competition with a few large species.
Small ruminant (sheep and goats) grazing
seems to control these two processes.
Conservation managers should, therefore,
reconsider the role of grazing in maintaining the desired ecological state in their
reserves, in a similar way to land managers who integrate sheep grazing into rehabilitation projects in the northern Negev
[22].
The historical fear that traditional grazing
eventually leads to degradation and overgrazing and, therefore, must be excluded
from any protected area, should receive a
second examination. In light of our longterm monitoring of rangeland productivity
and herbaceous community structure we
conclude that grazing, even heavy grazing, does not induce degradation. We
claim that Old World grazing-determined
systems are not prone to grazing impact
but rather are mainly affected by climatic
conditions [9]. It seems that much of the
overgrazing syndrome has stemmed from
prejudice, political conflicts, and lack of
ecological knowledge. We should not
base conservation practice on such a
shaky foundation.
Nature reserves in the Negev
In the south of the country, the unique
desert ecosystem is also endangered,
mainly by pressure from development
plans. Further scientific research is required to understand the desert ecosystems, to
explain the mechanisms involved, and
thereafter to prescribe the correct balance
among livestock grazing, reintroduction of
extinct wildlife, proper road construction
and tourist accommodation.
Recognition of the need to protect natural
and landscape resources led to the enactment of the National Parks and Nature
Reserves Law in 1963, and the Nature
197
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and National Parks Protection Authority in
Israel, established in 1964, was given a
mandate for the protection of natural habitats, natural assets, wildlife, and sites of
scientific, historic, architectural and educational interest in Israel. The Authority is
part of the Ministry of the Environment. The
establishment of nature reserves and national parks, and the designation of protected
natural assets are done in accordance
with this law, which prohibits the taking,
destroying, possessing or trading in protected natural assets, except with the permission of the Authority.
Israeli law defines a nature reserve as an
area containing unique and characteristic
animal, plant and mineral forms which
must be protected from any undesirable
changes in their appearance, biological
composition or evolution. National parks,
which also play a role in preserving open
spaces in Israel, are defined in Israeli law
as areas of natural, scenic, historic,
archeological or architectural value,
which are protected and developed for
recreational purposes. Both kinds of protected areas serve to safeguard the natural
landscape from rapidly encroaching urbanization. Outside the confines of the nature
reserves, hundreds of plant and animal
species, as well as inanimate natural
assets such as fossils and beachrock, have
been declared “protected natural assets”.
Israel’s reserves and national parks are
under the responsibility of the Authority.
They vary in size, character and use.
Some encompass less than one hectare
(e.g., temporary rain pools), others span
more than 1,000 hectares (desert reserves); most are open to the public and some
offer special visitor services. Together, they
represent the entire spectrum of Israel’s
ecosystems, including Mediterranean
forests, marine habitats, sand dunes, freshwater bodies, desert oases and crater
landscapes. To date, nearly 25% of the
area of Israel is under legal protection,
although none of Israel’s reserves is large
enough to preserve entire ecological systems that encompass a variety of habitats.
In the Negev, the protected areas are
mainly in the most arid, southern part,
whereas the northern Negev has been
given over primarily to agriculture. Rocky
areas are well represented among the
reserves, but the formerly extensive sandy
semidesert steppes of the Negev have
nearly disappeared under agricultural
pressure, and are represented mainly by
one nature reserve that covers 4 sq. km.
Wildlife and conservation
in the Negev
Relative to its geographical size, Israel has
a rich faunal biodiversity. Thus, for
198
example, Europe, which is 300 times larger than Israel, supports about 140 terrestrial mammals, compared with 106 mammals known to exist in Israel until the
beginning of the 20th century, when several species of vertebrates, mostly mammals, disappeared from Israel. The introduction of firearms into the Middle East by
the end of the 19th century, and the tradition of hunting led to the disappearance of
four ungulates (roe deer, fallow deer, Arabian oryx and Syrian onager), three carnivores (Syrian bear, cheetah, and the northern subspecies of the leopard), the ostrich
and the Nile crocodile. Native ungulates
in the arid parts of Israel comprise mainly
the ibex (Capra nubiana), with a population of about 800, and the gazelle
(Gazella gazelle acacia), of which
about 200 remain3.
The Wildlife Protection Law of 1955 has
proved to be an effective instrument in the
protection of wildlife in Israel. This law,
designed to protect birds, mammals, reptiles and amphibians, has been responsible
for the recovery of many dwindling species. The population of the mountain
gazelle, as with other species, has
increased from few hundreds to several
thousands as a result of legal protection
and enforcement. The law defines protected wildlife as any animal that has not been
designated as a “pest” or “game”; it requires a hunting license to be obtained from
the Authority for game hunting or for the
extermination of pests, and prohibits the
hunting of protected species except by
special permit and for the specific purposes listed in the law. In addition, the law
prohibits certain methods of hunting, including the use of traps, explosives, poisoning,
and shooting from a moving vehicle. Hunting of game and pests is restricted to the
hunting season and to limited areas, and
requires a license and strict compliance
with established guidelines. The import,
export and maintenance of wildlife in
Israel are also regulated by the Nature
and Parks Authority (NPA), in accordance
with these laws.
As nature and wildlife protection gained
new prominence, major efforts were made
to rehabilitate and reintroduce some of
these species to the wild. In the 1960s, the
NPA set out to reintroduce populations of
animals that were present in historical
times, as confirmed by biblical references,
but that are no longer found within modern
Israel. Two breeding cores, Hai-Bar Carmel (1975) in the north of Israel and HaiBar Yotvata (1964) in the south, were
established to breed animals suitable for
release; the former for Mediterranean
3
Nature and Parks Authority census data.
species, the latter for desert species. The
founder animals of each species came
from all over the world, both from zoos
and from the wild. Five species have been
chosen: ostrich, roe deer, Asiatic wild ass,
Persian fallow deer and white oryx (also
known as Arabian Oryx). Of these, all
except the roe deer are globally endangered.
Israel’s reintroduction procedures closely
follow the World Conservation Union
(IUCN) recommendations. Successful reintroductions into the wild have already
been implemented for the Asiatic wild ass
(since 1982, nearly 100 individuals have
been released in the Makhtesh Ramon
area of the Negev desert), the fallow deer
(the first release took place in 1996 in the
Nahal Kziv area of Western Galilee), and,
most recently, the white oryx and the
ostrich. Israel’s herd of white oryx is located in the Hai-Bar Reserve in Yotvata, a
12-sq-km fenced reserve in the Arava valley, about 30km north of Eilat. The herd
was started from a nucleus of eight animals, brought in 1978 from the San Diego
Zoo where the captive herd of oryx was
created in the 1960s. Today, Israel’s herd
of 90 animals can support reintroduction,
and a program based on habituation
enclosures is being implemented. In
March 1997, 21 of these magnificent animals were released into the wild, equipped with radio-collar equipment and, in
the case of one female oryx, with a satellite transmitter.
Conclusion
The rangelands of Israel are unusual,
perhaps unique, in their combination of
rich biodiversity and long-term grazing
pressure exerted over several millennia.
This has caused us to wonder if pastoralism over evolutionary time has not, in fact,
contributed to high species richness, at
least in vegetation. It is worth noting that
rangelands in climatically comparable
regions in California and Australia, with
much shorter exposure to pastoralism,
show declines in plant species richness
and invasion of Eurasian and African
plant species when subjected to heavy
grazing pressure, whereas the rangelands
of the Levant seem relatively resilient and
may even lose diversity when grazing is
removed. This suggests a fundamental difference in adaptation to grazing, which is
extremely interesting and is worth further
investigation.
In Israel, the arid rangelands are under
threat, not from grazing, but from urban
and agricultural development. The remaining rangeland areas require vigilant
Sécheresse vol. 17, n° 1-2, janvier-juin 2006
conservation management, including grazing, if the next generation is to have at
least remnants left to study. ■
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