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Native to the Atlas Mountains of North Africa, every Barbary Sheep
in Britain is descended from a group imported by London Zoo in 1842.
Barbary Sheep owe their name to the old name for the North African
region, the Barbary coast.. They are now considered to be genetically
identical (homozygous). Adapted to parched, mountainous areas with
little cover they will often " freeze " if disturbed, rather
than run away, when their deep brown colour can make them, even
in our enclosure, sometimes difficult to see.
They
become surprisingly active in the early evening, when they will
indulge in racing and leaping. Males will often spar with each other,
clashing their massive horns with a loud thud. The horns are honeycombed
inside, and their rich blood supply would assist cooling in their
native Africa.
Glasgow
ZooPark acquired five in 1968 from Edinburgh Zoo, and has bred over
sixty animals since then. Glasgow bred Barbary Sheep can be found
in zoos as far afield as Bahrain and Singapore, as well as Blackpool
and Comrie Wildlife Park in Perthshire .
Classified
by IUCN the World Conservation Union as Vulnerable in their
native habitat. Ironically, there are thousands of Barbary Sheep
living in semi-liberty in canyons and arroyos of the semi-arid lands
of Arizona and New Mexico ; haven been released by ranchers anxious
to establish a species outwith USA legislation protecting native
species and therefore extend the trophy hunting season to all year-round.
Thought-provoking Questions:
Is
Dolly the world famous cloned sheep really a new scientific breakthrough
given that these Barbary Sheep are virtually clones too?
Where
animals are bred to provide sport for hunters, and would not otherwise
exist at all, is their life of any intrinsic value?
What
is man's relationship with the creatures with whom we share the
planet?
BARBARY SHEEP AT GLASGOW AND OTHER PLACES
by Richard O'Grady .
Barbary
sheep, or Aoudads, are popular zoo exhibits across Europe, usually
being used as the focal point of an artificial rock or mountain
exhibit, where in numbers they create an arresting sight.
In
the UK, since the closure of the Mappin Terraces at Regent's Park,
the closure of Windsor Safari park and the decision by Edinburgh
Zoo to discontinue keeping this species, opportunities for viewing
Barbaries at all, never mind in inspiring surroundings, are few
and far between. Dudley, Paignton, Blackpool, and here in Glasgow
spring immediately to mind, plus some in very small numbers in a
handful of other zoos and wildlife parks.
In
the 60's and early 70's, the Barbaries on the Mappins were magnificent.
Forty or fifty of these sand coloured animals, as alike as peas
in a pod with sleek shiny coats and short hooves, and multitudinous
youngsters made an indelible impression. When I commented one day
in 1974 (I think) to my companion, the then curator Dr. Michael
Brambell, on their general condition, he replied:
"
Yes, interesting isn't it, especially as they have had no fresh
blood since their first importation from abroad when the Mappins
first opened. "
Nearby
were a group of Mouflon, and he emphasised that the splashes of
white here and there on their faces and shins, were sure-fire evidence
of the introduction of domestic sheep blood in the past, " Not
like the ones at Whipsnade, which have been kept absolutely pure
since the thirties. "
At
Glasgow, the Barbary sheep are all descended from five animals acquired
from Edinburgh Zoo in 1968. These in turn were descended from animals
from Regent's Park acquired in the 1920's. When I first saw the
Edinburgh animals in 1965 they were kept in one of the top enclosures
on Corstorphine hill, mid-way between the large carnivores to the
east and the camels to the west. Kept on an earth paddock, under
trees, with just a few rock outcrops, overgrown hooves were a persistent
problem, and in wet weather the paddock quickly became unsightly.
The Zoo stopped keeping this species in the late 70's, early 80's.
By
1972/73, from five, Glasgow's group had built up to nearly twenty
animals. In 1974/75 we supplied Cyril Grace at the newly opened
Blackpool Zoo, with quite a sizeable group of six or eight animals.
The other significant herds, were at Dudley, Paignton and Windsor
Safari Park. All originated from Regent's Park stock it is believed.
The Dudley animals today consist of at least twenty kept entirely
on concrete and stone in quite a small area. Their physical condition
seems excellent. Paignton's group is usually maintained quite small.
Windsor's group originated, I think, from Glasgow via Ravensden
and at one time shared a drive through enclosure with baboons. When
the park closed a few years ago, I think this group went to the
Continent.
During
the 70's and 80's we bred at Glasgow nearly sixty Barbary sheep
whilst trying to maintain the group at between eight and twenty.
We disposed of numerous small, start up groups, to zoos, abroad
through Ravensden, including several to the Middle East.
Despite
their relatively long history in captivity there are few signs,
if any, of any deleterious effects appearing. A few people have
attempted to argue that the rapid hoof growth might be such an effect,
and whilst this might be possible, I disagree, for reasons I will
attempt to explain later. For the past 15 years, our group has produced
the occasional individual - currently we have two - with white areas
just above the rear hooves.
This
result is just as one would expect for one hundred years or more
of captive breeding of a fast breeding ungulate. As with Pere David's
deer, the first genetic bottlenecks occur when the original small
group of animals was imported or confined. Four or five generations
later one would expect, if there were to be any, the births of weakened
or deformed animals as the non-visible genetic characters were combined,
recombined and showed themselves before being discarded or immediately
dying. The remaining population, almost certainly, 98% homozygous,
i.e. identical, with little residual variation. This is not a problem
unless you decide to introduce " fresh blood " i.e. a totally
unrelated animal, from either a wild caught or North African population.
If you do this you go straight back to square one. As was pointed
out to me by Michael Brambell many years ago, the time to "re-combine"
these self-sustaining but inbred captive populations, is at the
release stage, but not before, unless for very specific and clearly
understood purposes. The maximum variation is then available to
the animals as they try to adapt and adjust to life once more in
the wild.
Despite
what I have just said, the chance to acquire a "fresh" animal from
another UK flock/herd should always be taken. As most stockbreeder/breeders
of ornamental birds, be they budgies or poultry understand, this
can result in a general improvement in fertility and physical vitality,
even if the blood lines being used appear to be genetically closely
related or line bred. It was for this reason that, in the late 1970's,
we acquired a Paignton bred, male Barbary sheep through Ravensden.
Similarly we agreed to Nick Ellerton's request to retain a young
Glasgow-bred Pere David's stag when it arrived at Chester on route
to Da Feng for the re-introduction project instead of letting it
proceed with the others. The Paignton-bred male Barbary sheep was,
in my subjective opinion, not very "good". He was smaller and his
horns were flatter than our own (a characteristic which lingered
for two or three generations in his offspring). We are now back
to our original type which possess more upright, curled-back horns.
To
facilitate the integration of this male into our group and to ensure
he had little or no competition we removed all of our adult males,
and have continued with just one adult male, two or three sub-adult
males with four to eight females ever since - until recently.
We
had always encountered problems with over growth of hooves especially
as, like Edinburgh Zoo before us, we kept our animals on a sloping
tree-covered, earthy hillside. About 15 years ago we built a substantial
concrete hard standing followed by some small sandstone climbing
hills.
Just
before I was appointed Director at Glasgow in 1972, our own magazine
"Zoo Life" featured a sequence of photographs of the late Reg Lowe,
the Kirkcaldy-based vet, using a dart-gun to immobilise our Barbaries
for foot trimming and I soon became familiar with this traumatic
and expensive routine. It became more traumatic than absolutely
necessary because the more experienced females became adept at spotting
not just Reg's Landrover, but the rifle or Reg himself, and would
start running immediately. On one poignant occasion, when I was
standing down at the far end of the enclosure just outside the fence
trying to ensure that no passers by were impaled on a stray dart
the entire herd came and stood next to me - someone they had grown
to trust during long summer evenings when apart from me and the
security guard there would be few people about.
Such
a tortuous business plagued both Edinburgh and ourselves resulting
in Edinburgh eventually, I believe, deciding to go out of this species.
Investigation of the situation at Regent's Park and Paignton showed
both collections routinely catching these animals by hand for pedicures,
a system I personally favour. However, it is dependent upon your
quality of stockmanship and the bureaucratic pressures your collection
may have to endure regarding Health and Safety, Risk Assessments
and such like.
The
experienced keepers who built up a close relationship with their
animals can usually grasp their horns "en passant" and upturn the
young one. However, distressing accidents can happen, so it is not
a operation to be undertaken lightly. Adult Barbary sheep, whilst
they are usually kept behind six foot fences, can clear them with
relative ease when excited, and once out are very difficult to re-capture.
We have seen them jumping onto roofs of adjacent buildings, before
jumping back into the enclosure and jumping for fun over six foot
internal fences by bouncing off the chain link where it pressed
a sloping tree. They are, fortunately, nowhere near as nimble as
the Markhor ram which one heart-stopping morning, Michael Brambell
saw walk out along the 35 degree, two by two, angle irons holding
the engirding fence at the rear and very top of the Mappins, where
it projected out over Regent's Park and the service area. When he
reached the end of the angle iron, at that point some twenty metres
above ground, he twiddled round before delicately picking his way
back into the enclosure again!
We
still dart our animals using our local licensed vet, a cumbersome
process which every February/March, when females are heavily pregnant
and have endured a long wet winter, results in quite a number of
untrimmed hooves because the opportunities for darting are restricted
especially as the hillside is exposed and windy.
At
the Mappins and the larger Barbary sheep exhibits on the continent,
I had always assumed that the numerous extra males were there mainly
for exhibition purposes. These were the bigger showier animals with
large horns and luxuriant flowing manes - an impression fostered
by the male-only exhibits shared with primates in other collections.
I am now increasingly of the opinion that this is the way that these
animals should be kept if they are " to behave properly
".
With
just one adult dominant male the situation is quite abnormal. The
group is very settled, with no evident stress. Activity levels are
low, with it is argued, resultant over-rapid hoof growth. The adult
male becomes tamer and tamer with his keepers until he eventually
becomes a danger - especially to anyone working in this section
alone - a situation with medium-sized ungulates, memorably portrayed
by Hediger many years ago. It is possible that the Barbary ram is
compensating for the lack of other males to spar and wrestle with
in the typical locked-horn Barbary manner. These extra males are
a necessary release for pent-up stress (or is it boredom?). Because
there are additional males, who are always on the look-out for extra
mating opportunities, the herd is kept, if not constantly on the
move, well-chivvied, with possibly a beneficial effect on rate of
hoof-wear.
Barbary
sheep are adapted to live in arid areas. In conditions of plenty
in captivity, they will sometimes breed twice a year, and nearly
always do so if they loose the first lamb or lambs in March - so
there is every incentive for the males to keep checking for signs
of oestrus in the females, despite the increasing day length in
the spring and in early summer.
The
question of their longevity should also perhaps be addressed. Our
females routinely live until they are thirteen or fourteen years
old. Long before this they find themselves with few if any teeth
- which need not be a problem if the vegetables are cut up small.
The heavy foot growth is probably an adaptation to the hard, abrasive,
sandstone of the Atlas mountains. In the wild they would be unlikely
to survive past the age of six or eight. We find the hooves of these
very old animals extremely difficult to keep trimmed back properly
because of the extension of the main blood vessels through the hoof.
Sometimes indeed, we have been forced to consider culling certain
individuals for this reason alone. It is perhaps a feature of their
management which herd owners have been carrying out routinely through
the years, without appreciating or rationalising why they have done
so. It is possible that the combination of an excellent diet, excessive
longevity and extremely rapid hoof growth results in conditions
so abnormal as to inevitably produce animals which after the age
of ten or twelve are bound to create a difficult or ethical dilemma
if they are to be exhibited in a 100% perfect condition. Over the
next year or two I hope to find out from other collections, if possible,
what the maximum longevity of individual animals is in their herds.
I would also like to visit the naturalised Barbaries in Arizona
where herds are reputed to total thousands in number after their
initial introduction by wealthy ranchers looking for something to
hunt outwith the control of American game laws. I would like to
see if the males spend most of the year in bachelor herds as do
many other mountainous ungulates, and the amounts and types of activity
present.
In
the meantime every time my eye rests on our small group of Barbary
sheep far from dismissing them as so common as to be unworthy of
interest, my imagination is stimulated by their visual appeal and
the success of their long term captive breeding in Zoos.
This article first appeared in Zoo! Issue No. 10, Summer 1998, the
magazine of the Independent Zoo Enthusiasts Society, and is reproduced
by courtesy of the Editor. Further information about the Independent
Zoo Enthusiasts Society can be obtained by sending a SAE to: the
Independent Zoo Enthusiasts Society, PO Box 4, TODMORDON, Lancs.
OL14 6DA.
BARBARY
SHEEP, Ammotragus lervia
by
Richard O'Grady
The
little Barbary sheep lamb, born this year, is the latest birth
in our small flock. For me, the births each year of this species
are highly symbolic, representing over 150 years of captive breeding
in the U.K. with no fresh blood! Looking at this lamb, it is clear
it is as fit and well as if it was running with its relatives
in the Atlas Mountains of North Africa. How is this so?
The ancestors of all the Barbary sheep in the U.K. were imported
by the Zoological Society of London for Regent's Park Zoo in 1842.
Their descendants were eventually part of the top exhibit on the
Hagenbeck-style, artificial mountain of the Mappin Terraces. From
here a group was sent to the newly opened Edinburgh Zoo in the
1920s. In 1968, Calderpark Zoo -as it then was - acquired five
from Edinburgh. We have been breeding them every year ever since,
whilst both Regent's Park and Edinburgh Zoos have dispersed their
herds, in London's case, abroad and out of the country.
Careful research has shown no fresh blood. Two animals were imported
by London earlier in the twentieth century but these never bred
and, in fact, died within a year or eighteen months.
The remaining animals can now be regarded as homozygous and genetically
around 98% identical. They are virtually trouble free. The only
signs I can see of any domestication is that two of our animals,
and another three in the past, have white hind feet. The explanation
for this is that all the deleterious factors have previously occurred
and been removed, either by being born dead, not surviving, or
by culling. When animals are reduced to a very small number before
increasing again, genetic variation is invariably lost.
This phenomenon is known as a 'genetic bottleneck' and
occurs naturally. It is believed, for example, that African cheetahs
have been through several such genetic bottlenecks in the wild
during the past 10,000 years, with a consequent reduction in genetic
diversity. Current captive cheetah breeding programmes are focussed
on maintaining such naturally reduced genetic diversity as much
as possible, without losing any more through mismanagement.
Père David's deer is another species which has undergone
several genetic bottlenecks. The first obvious one occurred when
the population was enclosed in the walled grounds of the Imperial
Hunting Palace. For the next one thousand years this population
existed in isolation. Then sixteen animals were removed to European
zoos in the early years of the twentieth century, which created
another bottleneck! All Père Davids deer alive today
are descended from these sixteen animals!
Yet it is patently evident that Père David's deer and Barbary
sheep, and even cheetahs for that matter, do not suffer from inbreeding
depression. There are no 'bulldogs', no lethal genes,
and no obvious behavioural abnormalities.
The principle of adding fresh blood is frequently
misunderstood by animal breeders. There is an implicit assumption
that this is a good thing, to be encouraged. This is not necessarily
so. If adding fresh blood means reintroducing to the captive U.K.
population deleterious factors, long since previously removed,
then this should be resisted. This would happen if, for example,
someone imported a Barbary sheep direct from the wild. The time
to gather together animals from a number of sources is when a
release back into the wild habitat is being contemplated. The
resultant variation amongst the off-spring would then provide
the maximum material for natural selection to work upon.
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