 
During recent decades populations of houbara are believed to have
declined drastically throughout the entire distribution range.
Over-hunting and severe habitat degradation appear to be the main
causes of the decline. While the species has been able to survive
a long tradition of falconry in Saudi Arabia, the widespread availability
of modern fire-arms and four-wheel-drive vehicles has made even
the most remote populations vulnerable to hunting, and contributed
significantly to the alarming decline over the last twenty years.
Overgrazing of the fragile desert flora by domestic livestock
has also caused massive loss of habitat for houbara.
Of all the bustard species, the houbara is the one most adapted
to the desert environment. Separated in three subspecies, the
houbara of the genus Chlamydotis is distributed over a wide range.
The nominate subspecies Chlamydotis undulata undulata inhabits
the north African range. Chlamydotis u. fuertanturae occurs only
on the Canary Islands and Chlamydotis u. macqueenii, of interest
to Saudi Arabia, ranges from Sinai to western Mongolia. The houbara
is thought to be resident in North Africa and the Canary Islands
whilst the populations breeding in central Asia are migratory,
wintering from Pakistan to Arabia where they overlap with the
local breeding populations.
The official IUCN category for the houbara is Vulnerable, which
includes populations that are seriously depleted, or decreasing
due to over-exploitation or other factors, and which are at risk
of becoming Endangered if causal factors continue unchecked.
The great cultural value of houbara in Saudi Arabia, and concern
about the possible extinction of local populations, prompted the
National Commission for Wildlife Conservation and Development
(NCWCD) to take conservation measures. These include the identification
of suitable habitat, habitat protection, studies of free-ranging
populations, the foundation of a captive breeding population,
and studies on feasibility of eventual reintroduction and restocking.
In 1986 Harrat Al Harrah Protected Area was established around
the last known houbara breeding area in Saudi Arabia. This reserve
(12,000 km2) of sand, wadis and black basaltic rocks, is located
in the northwestern part of Saudi Arabia, near the border with
Jordan. Hunting is forbidden and grazing livestock is restricted
to camels. In 1989 a second protected area was established at
Mahazat As Said and the entire 2200 km2 area was fenced to assure
complete protection against hunting and grazing.
In Harrat Al Harrah, between 1987 and 1991 searches for evidence
of breeding were undertaken. The population was found to be small
and patchily distributed, and only six houbara breeding attempts
were recorded in the reserve between March 1987 and July 1990.
Two researchers of the NWRC, P.Seddon and Y. van Heezik began
field studies at Al Harrah in November 1991, focussing on habitat
utilization and documentation of seasonal changes in houbara density.
The identification of specific habitats utilized by houbara may
assist in the location of suitable areas for protection, and possible
new release sites for reintroduction of captive-reared dirds.
Surveys showed seasonal changes in the numbers of houbara. The
population of houbara resident in the reserve in spring is probably
less than 100 birds and only eight breeding attempts were recorded
in 1992. Given that Harrat Al Harrah was set aside as the possibly
the last breeding location of houbara in Saudi Arabia, these figures
are very low indeed. Several questions remain to be answered:
where do the houbara that over-winter in Saudi Arabia come from,
and is there a clear distinction between resident and migratory
populations? To answer these questions satellite and conventional
radio tracking studies are planned, but progress depends upon
the ability of biologists to trap these cryptic and wary birds.
A captive breeding programme based at the National Wildlife Research
Centre in Taif, managed by P.Paillat and P. Gaucher , began in
1986, utilizing breeding stock from Baluchistan and Algeria. As
the species is known to lay a replacement clutch, authorization
was obtained from the two governments concerned to collect eggs
from breeding populations at the beginning of the reproductive
season in order to minimize possible detrimental impact on the
wild populations. One hundred and three chicks of the Asian subspecies
Chlamydotis undulata macqueenii and 129 chicks of the African
subspecies Chlamydotis undulata undulata contributed to the breeding
stock.
At the beginning of the project very little was known about the
reproductive biology of the species. In North Africa eggs are
usually laid between February and May but, occasionally, eggs
were found in Algeria as early as November or as late as June.
In Syria one can find eggs between March and May and in southern
Russia between April and June. Some authors believe that rainfall
is an important trigger for breeding and that this does not occur
in dry years. It was believed that sexual maturity was achieved
at two years old and the houbara was known to lay a single clutch
of one to four eggs.
Our captive brood-stock provided an opportunity to take a closer
examination of the houbara’s breeding biology. One of the first
results was that when plentiful food was available throughout
the year, the birds showed a seasonal breeding pattern with the
laying period extending from January to July. We developed the
hypothesis that an endogenous rhythm may have evolved to regulate
the annual reproductive cycle. Synchronising factors are most
likely to be seasonal temperature changes with rainfall acting
as a secondary factor, perhaps leading to a lengthening of the
reproductive period and thus allowing second clutches to be laid.
Although captive, well-fed houbara are able to lay from one year
old (6% of females), most undergo delay of maturity until they
reach three or even four years old. As one might expect, older
birds tend to lay more eggs. Records derived from egg removals
and stimulation of replacement clutches showed that the mean number
of eggs laid by C.u. macqueenii ranged from 1.7 for one year old
birds to 11.8 for those older than 3 years. Nevertheless there
is considerable variability in clutch size within each age class
with the maximum eggs laid by one female in a single breeding
season being 30 for C.u.macqueenii compared with 20 for C.u.undulata.
Reproductive parameters for these two subspecies are rather similar
although macqueenii generally displays greater reproductive capacity;
larger clutch size and smaller inter-clutch intervals.
Several natural management techniques were tested during the course
of developing a successful breeding strategy: isolated pairs;
heterosexual groups of various sizes and selective access to the
male via doors allowing only female passage. The search for an
optimal system continues since all of these methods yielded relatively
poor results with only 20% to 50% of the eggs being fertile. Problems
with natural breeding techniques led to the adoption of artificial
insemination. Sperm are collected using a dummy female presented
to a displaying male. When the unsuspecting male attempts to copulate
with the model-female, the manipulator collects the sperm. Immediately
after collection sperm is diluted and analyzed for concentration
and motility and then inseminated directly into the entrance of
the vagina of a receptive female. By improving the insemination
techniques the level of fertility increased from 50% in 1989 to
85% in 1993.
The release programme of the Asian subspecies, macqueenii, began
in 1992, under direction of Olivier Combreau. Since the programme
is still in its early stages relatively few results are available.
For re-introductions to be successful the actual release techniques
are a vital element in the programme. Even in suitable habitats,
captive bred birds may experience difficulties in adapting to
their new environmental conditions. Difficulties they encounter
include locating food, spatial orientation, avoidance of predators,
and resistance to infection. Both age and composition within social
groups are also factors that have a bearing on the ability of
released birds to survive in the wild.
In order to examine these aspects in more detail release experiments
were conducted in a 4 km2 mammal predator-proof pre-release enclosure
situated within the much larger 2200 km2 fenced and protected
area of the Mahazat As Said reserve. Pre-release cages were located
within alfalfa plots in the protected compound. Different techniques
were then tested with birds from one month to several years old,
all of which were subsequently tracked through solar powered radio-transmitters
with which they had been fitted. Trackers following the birds
from ground vehicles and light aircraft gather information concerning
their survival, dispersion, habitat utilization and social behaviour.
An earlier attempt at such a release programme, conducted in 1991,
failed when, within five days of their release, all of the captive
reared houbara were eaten by foxes. In 1992 coveys of two chicks
and a foster mother held for fifteen days in the cages and then
set free within the pre-release protected enclosure, also gave
disappointing results. The coveys showed a very high dependence
upon supplementary food and the hoped for apprenticeship in wild
feeding techniques, natural food selection, habitat utilization
and predator avoidance by the adult females did not live up to
expectations. On the other hand, sub-adult release, using birds
of around one and a half months old which were translocated from
the breeding unit to the pre-release cages gave somewhat better
results. Out of 31 sub-adults thus released, approximately 50%
were still alive inside the reserve six to ten months after their
release. It is too early to draw any conclusions about the release
experiments but the results obtained so far with sub-adults are
certainly the most encouraging. In the forthcoming breeding season
we shall be trying a variety of chick-rearing techniques aimed
at enhancing the birds’ ability to survive later in the wild.
In September 1993 an international workshop was organized by the
NCWCD in Saudi Arabia with the aim of reviewing progress and mapping
future directions of the houbara programme. Workshop participants
drafted recommendations that have formed a basis for a conservation
strategy. The recommendations include measures to improve houbara
habitat in Saudi Arabia, maintenance of a captive breeding programme,
development of techniques for captive rearing and release of captive
bred birds, promotion of public awareness and fostering of public
support for houbara conservation and, finally, taking a lead in
initiating cooperative conservation efforts between houbara range
states.
Captive propagation of the houbara has proven to be a difficult
task. After a disheartening year of infertile eggs, the first
breeding success was achieved in 1989 with the reproduction of
17 chicks. Fifty-five chicks were produced in 1990, 49 in 1991,
138 in 1992 from 60 laying females, and a record 283 chicks in
1993 from 75 laying females, allowing the release experiments
to begin in earnest.