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The northern bald ibis is on
the brink of extinction. Less than two hundred birds remain
in the wild. Scientists are doing their utmost to protect
these last survivors. Breeding programmes and international
conservation have proven quite successful.
On the inaccessible cliffs of Souss-Massa
National Park in Morocco breeds a mystic bird, legendary
and extremely rare, and, as some might argue, strikingly
ugly. With its naked, wrinkled and reddish face and a crest
of long feathers on the back of its head, the northern bald
ibis has always fascinated man, probably because of its
weird appearance and the metallic green and purple gloss
on its black feathers. The scientific name Geronticus eremita
refers to its resemblance to an old man, bald and wrinkled,
and to the fact that, like a hermit, it prefers remote places.
The northern bald ibis, belonging to the bird family that
also includes storks and spoonbills, was once widespread
across northern Africa, the Middle East and even the Alps.
Over the past few centuries the species has undergone a
dramatic decline and is now listed as critically endangered.
Populations in Europe and the Middle East went extinct,
and by 1997 worldwide numbers had fallen to fewer than 50
pairs. Remarkably, northern bald ibises reproduce well in
captivity. Although in the 1940s the first captive birds
died soon after arrival, the next imports in the late 1950s
survived and became the founders of the present zoo population.
Presently it includes around 1000 captive birds in Europe,
North America and Japan. "Ironically for the species, there
are now more individuals in zoos than in the wild", says
Christiane Böhm, a biologist at the Austrian Alpenzoo in
Innsbruck, one of the largest breeding stations. "Fortunately
the wild population of bald ibis is now doing slightly better",
she adds. "Thanks to intense conservation efforts, the Moroccan
colony has increased to around 85 pairs."
Discovery of a hidden colony
"The main threat to the birds is human disturbance and hunting",
Böhm explains. "Habitat loss and pesticide poisoning have
also taken their toll." In Europe, however, the species
disappeared as early as the 15th or 16th century. "No-one
knows exactly why that happened," she continues. "Written
sources are rare and vague, but it is likely that in addition
to hunting pressure, changes in climate played a role."
Religious traditions caused one Turkish colony to survive
long after the species had disappeared from the rest of
Europe. According to local legend, the ibis was one of the
first birds that Noah released from the Ark. People believed
that the bird migrated each year to guide pilgrims travelling
to Mecca. The ibis was protected by its status, and a festival
was held each year to celebrate its return. "Today there
is still a semi-wild population in Turkey", says Böhm. "The
birds fly freely during the breeding season. They breed
outside the cages, and feed along the Euphrates river. However,
these birds do not migrate. In winter they are kept in cages
and receive supplementary food." This breeding station was
established in 1977 when only 34 wild birds returned from
the wintering grounds. The number of returning birds declined
gradually and in 1990 only one bird returned - the last
representative of this wild colony. In 2002, scientists
made a surprising discovery in the desert of central Syria.
"The eastern population was thought to have gone extinct",
says Böhm, "but scientists found three breeding pairs, incubating
eggs, and a seventh adult." Since the 1990s there had been
sporadic sightings of northern bald ibises in Saudi Arabia
and Eritrea, suggesting that a breeding population still
existed somewhere in the region. "The discovery of this
colony might mean that there are other hidden colonies",
she notes.
Protection across borders
Böhm is an active member of the International Advisory Group
on the Northern Bald Ibis (IAGNBI). This group aims to promote
international cooperation on the conservation of the northern
bald ibis, both in captivity and in the wild. International
cooperation is needed since the wild birds do not stay within
country borders: they migrate between breeding and wintering
grounds. Conservation in one country is useless if threats
in another country remain. To protect migratory waterbirds
internationally, a treaty was established in 1995: the African
Eurasian Waterbird Agreement (AEWA). Currently 48 countries,
ranging from Sweden, Lithuania and Uzbekistan to Senegal,
South Africa and Mauritius, have signed the Agreement. Through
international regulations, monitoring, coordination and
concrete projects, AEWA forms a framework for waterbird
protection in the African-Eurasian flyway. "Together with
AEWA, IAGNBI is now working on a so-called Action Plan for
the species", says Böhm. "This Action Plan lists concrete
conservation priorities, such as safeguarding the existing
breeding sites, surveying areas for possible remnant colonies,
and monitoring the migration of the northern bald ibis."
In Morocco monitoring is done by fitting adult birds with
radio transmitters, which allows scientists to track their
movements in detail. "Such information is immensely important",
Böhm notes. "At present we know very little of the species'
ecology, and baseline information is needed to develop effective
protection strategies." IAGNBI organised an international
workshop in 2003, co-sponsored by AEWA, where people involved
with northern bald ibises gathered to exchange experiences.
Learning to migrate
One remarkable project coordinated by IAGNBI is the reintroduction
into the wild of captive-bred birds. There is just one problem
with reintroduction: captive birds have never learned to
migrate. With a diet that consists mainly of insects and
small reptiles, northern bald ibises need to move southward
in winter in order to find enough food. "A team of biologists
in Austria is now trying to teach the birds to migrate,"
tells Böhm. "They train young birds to follow micro-light
airplanes, and show them the way across the Alps to warmer
valleys in Tuscany." Böhm remains moderately enthusiastic
about these efforts. "We don't really know why the European
population went extinct. It might not have been because
of human factors. It might be better to focus our attention
on the existing populations in Morocco and Syria. Nevertheless
it is very useful to gain experiences with establishing
a self-sustaining and free-flying population in the wild.
This provides necessary information on possible reintroductions
elsewhere." Reintroductions have the goal of creating additional
wild populations, not supplementing existing ones. This
would entail a risk for the fragile wild populations, which
might be susceptible to diseases carried by captive-bred
individuals. "A detailed and tested release method for a
migratory population has not yet been identified", says
Böhm. "We need to be extremely cautious, especially in areas
close to wild colonies." In addition, she adds, there is
no immediate urgency for reintroduction. Thanks to intense
conservation and coordination efforts, the species seems
to be slowly on its way back from the brink of extinction.
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