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The woods around Mudumalai in southern India are home to some of the
biggest and safest populations of elephants left in Asia. But even here
their future is uncertain. The forest seems secure enough – the trees are
deciduous and mostly too spindly to fell for timber – but it is interlaced
with farmland and villages. At the edges of the fields farmers have built
flimsy towers where they sit all night through the growing season, ready
to drive away elephants with firecrackers, torches and loudspeakers.

In Mudumalai, we see the plight and the paradox of the Asian elephant,
Elephas maximus. There may seem to be plenty of elephants left – tens of
thousands in Asia as a whole – but their habitat is fragmented, so that
many populations are too small and isolated to be viable. And everywhere
the ele-phants are in conflict with a human population that is already vast
and must increase over the next few decades.

How many elephants will Asia be able to support by the middle of the
21st century, when its human population has doubled – and India alone expects
to have 1.6 billion people? This is what elephant biologists from around
the world are trying to answer. All agree that unless good biology is now
combined with a strong political will, the future for E. maximus will be
grim.

Nobody knows exactly how many elephants are left in Asia. They mostly
live in the forest and so are difficult to count. Many also live in ‘politically
sensitive’ countries, such as Cambodia, where there is little opportunity
to count them. But estimates suggest there are between 34 000 and 56 000
Asian elephants, of which perhaps 10 000 are working animals living in captivity.
By contrast, there are probably 500 000 or more elephants in Africa.

The decline of the Asian elephant in recent centuries has been dramatic.
It originally evolved in Africa, alongside the ancestors of Loxo-donta africana,
the present-day African elephant. Loxo-donta stayed put, but a few million
years ago Elephas moved out and east into Asia. Just a few centuries ago,
millions roamed over the continent from Mesopotamia through Persia to China
and even to the islands on the extremities of Asia – Sri Lanka, Sumatra,
Borneo and Java. Now Elephas is gone from the Middle East and Java, and
reduced to remnants in China (about 500 animals survive) and Nepal (about
60). Only a few countries still have substantial numbers: India has about
25 000, Burma between 6000 and 10 000.

For Africa’s elephants, the chief problem has been ivory poaching. But
only a small proportion of Asian elephants, usually males, have big tusks.
For Asia’s elephants the main difficulty is one of space – their habitat
now consists almost entirely of pockets of land, each too small to sustain
viable populations.

According to Raman Sukumar of the Indian Institute of Science, Bangalore,
and deputy chairman of the Asian Elephant Specialist Group, wild Asian elephants
now occupy about 436 000 square kilometres, of which only 132 000 square
kilometres are in reserves. If we assume the total population is around
45 000, this works out at about 3 square kilometres of conserved land per
animal. That would be very tight even if elephants were left in peace. But
of course they are not.

One of the greatest sources of conflict is crop raiding. Females and
juveniles tend to do most damage because they always raid in herds, but
the solitary bulls raid far more frequently. The elephants know exactly
what they want. Finger millet is the main target in the south of India,
and the elephants make a beeline for the maturing crop. They also seek out
the succulent central shoots of coconut trees, pushing over bigger trees
to get at them. From mangoes and maize they sel-ect the flowering shoots,
and elephants will split banana plants to get at the central pith.

Adult bulls may obtain up to 30 per cent of their food from finger millet
in the growing season during October to December. What is not eaten is
trampled. In a single night, a bull might eat 75 kilograms of millet and
damage $60 worth of grain. The same bull might also destroy 15 mature coconut
trees, which would cost the farmer about $600 a year for about a decade
until replacements have had a chance to grow. In his book The Asian Elephant,
Ecology and Management (Cambridge University Press, 1993) Sukumar estimates
that the 6500 elephants of southern India cost local farmers around $500
000 a year.

Dangerous pursuits

Some of the traditional methods used to keep the elephants at bay are
hair-raising. The towers beside the fields may be flimsy but at least the
farmers who sit in these are reasonably safe as they try to drive the raiders
away. Others attempt the same feat from huts on the ground, which can be
fatal. Elephants are almost as likely to charge at flashlights as to run
away. They will also chase barking dogs, which promptly run back to their
masters with the elephant in pursuit. Shotguns, sometimes fired point-blank
into the raiders’ faces, increase the risk of injury to the farmer and leave
the animals with horrible wounds.

Some farmers go to the trouble, and expense, of digging trenches around
farms, but elephants will destroy these by pushing earth in with their feet.
Lining trenches with stone or concrete prevents this, but is costly. Electric
fences are another solution, and are more effective in Asia than in Africa,
where the elephants may use their bigger tusks to yank the fences out.
But the fences are expensive and cost-effective only for high-value crops
such as coconuts.

So what can be done? In the short term, farmers should receive compensation
for crop damage. In India, many state governments are already making such
payments promptly and without hassle. This is vital, for conservation cannot
succeed without the consent of local people. Sometimes, the problem can
be solved by moving elephants to areas where there are fewer people (though
these are becoming hard to find), or by capturing and domesti-cating animals
that are known to be troublesome. The long-term solution must be to provide
vast reserves, though it is hard to see where. More realistically, though
this too has its problems, biologists call for more ‘jungle corridors’
to link the fragmented habitats and prevent inbreeding.

This leads on to the grand strategic questions. How must the forests,
farms and cities be arranged if elephants are to live in harmony with people?
How can elephants be fitted into the new Asian economy? Clearly, the issues
are social, economic and political, but they are also biological. Ajay Desai
of the Bombay Natural History Society says that the fewer elephants there
are, and the smaller the space that is left to them, the more adroitly they
will need to be managed. If we are to conserve elephants, we must understand
their behaviour and all aspects of their ecology.

Food for thought

The studies are in progress and, encouragingly, they are being led and
carried out by Asian scientists. Perhaps the most basic ecological question
concerns what the elephants need to eat. It is already clear that they are
among the most versatile of all herbivores. They both browse on the leaves
of trees and shrubs and graze grasses. They have been observed to consume
up to 400 different species of plant in the forests of Malaysia, and 112
species in the deciduous forest of southern India. However, most of these
come from just a few plant groups, including those of the mallow family,
legumes, palms, sedges and grasses. In southern India, just five species
account for 85 per cent of the elephants’ total intake.

Whether elephants need this variety to stay healthy is uncertain, although
research suggests that they might. On the broad scale, their diet must contain
5 per cent protein just to maintain body tissue. This may seem a high figure
but only a proportion of plant protein can be digested and used. Grass at
certain times of the year may contain as little as 2.5 per cent protein.
By contrast, the leaves of some of the mallows contain 8 per cent, and those
of legumes such as acacia up to 20 per cent. So a balance of grazing and
browsing seems ideal given that excess protein entails nitrogen excretion,
which in turn increases their need for water.

The need for micronutrients might also encourage the animals to eat
a variety of food. For example, elephants eat a lot of bark, which perhaps
help them to meet their bodies’ considerable demand for calcium, trace metals
such as boron, copper and manganese, and perhaps linoleic acid, an essential
fatty acid. Vitamin B12 is a potential problem for herbivores, but can be
synthesised by gut bacteria, provided they have enough of the trace metal,
cobalt. Palms are rich in cobalt.

Water is also essential. Elephants do not need to drink every day and
they are known to survive for several days without water. Yet adults consume
up to 100 litres at a time, and up to 225 litres in a day. Overall, elephants
must pursue an ‘optimum foraging strategy’, which means obtaining the required
diet with the least effort and risk. For elephants, says Sukumar, this means
‘striking a compromise between food and water. Both may not necessarily
be available at their best in the same area.’

Question of space

So the question of how much space an elephant needs is not easy to answer.
It depends on whether that space contains all the sustenance that elephants
need, for this year, next year and in the worst foreseeable years. In practice,
an individual elephant will range over hundreds of square kilometres in
the course of a season, even though the food consumed that season could
theoretically be produced in a much smaller area.

Sustenance per elephant is not the only consideration, however. A general
rule of thumb says that no population of animals is liable to survive in
the long term unless it contains at least 50 individuals; another is that
no population can continue to evolve and adapt to changing circumstance
unless it includes at least 500 individuals. So to support a viable population
an area must contain enough sustenance for 50 elephants, and preferably
many more.

Finally, the issue of space is complicated by the elephants’ social
life. The females live in herds of up to about 20 individuals, with their
sisters, daughters, cousins, nieces and granddaughters. The herds in turn
join up with other herds, to which they are presumed to be related, to form
‘clans’. The males leave their mother’s herd when they are five years old,
but then attach themselves to other herds in the clan. At around 15 years
of age, they begin the increasingly solitary life that they will pursue
for the rest of their days, ranging across vast areas inhabited by several
clans. No one knows how important the clan structure is to the wellbeing
of elephants, but it seems reasonable to suggest that truly viable popu-lations
should encompass entire clans.

Overall, Sukumar and his colleagues found that clans in southern India
included 50 to 200 individuals, and that in the course of a year each clan
ranged over 100 to 300 square kilometres. This gives roughly 2 square kilometres
per elephant. But this, says Sukumar, should be regarded as a minimum size;
the area he studied is good elephant country. From these figures, the 132
000 square kilometres of protected area available to Asia’s 45 000 or so
elephants is definitely on the tight side; they clearly need the extra 300
000 or so square kilometres of unprotected land that they also inhabit.

Despite the problems of habitat loss and human conflict, there are some
points in the elephants’ favour. Biological factors that favour them include
their longevity (up to 70 years) and long reproductive life (from late teens
to 50 plus for wild cows, and from about 25 to 50 or so for wild bulls).
This ensures that they also have a long generation time – the interval between
one generation and the next averages 30 years – which is extremely helpful
for genetic reasons.

In general, a high degree of genetic variation increases the viability
of a population, and big populations tend to be more viable than small ones
because they can contain more genetic variation. But small populations of
animals with long generation times are more viable, genetically speaking,
than small populations with short generation times. Each parent passes on
only half of its genes to each offspring, and so populations tend to lose
genetic variation when the animals reproduce. Elephants, therefore, will
lose genetic variations more slowly than animals, such as mice, which have
short generation times.

Although so many of Asia’s elephants live in highly fragmented groups,
with only a few animals in each group, these small groups are more viable
than they may seem. For this reason, as Charles Santiapillai of the World
Wide Fund for Nature (WWF) argues, we should not simply write off the small
populations of, say, Nepal. The several hundred left in China certainly
deserve all the attention possible.

Some economic forces also favour elephants. The 10 000 or so working
elephants are doing vital work, mostly in the timber industry. Two-thirds
of them are females, which are far easier to handle than the stronger,
erratic males, and most of them are adult, because working elephants are
mostly caught in the wild when they are already old enough to work. As Michael
Woodford, a veterinary consultant based in Washington DC, points out, perhaps
as many as a third of Asian elephant females of breeding age are in work
camps. Unfortunately, camps in the past have discouraged breeding, because
a cow in late pregnancy or with a calf at heel does less work, and juveniles
do little useful work until they are at least 12 years old.

Several work camps have now agreed to aim to increase breeding, not
least those in Burma which has several thousand working elephants. Under
the guidance of vet Khyne U Mar, Burma is developing a programme of artificial
insemination.

But whatever is done to save Asian elephants, many more seem bound
to disappear. In northern India as many as 40 per cent live in areas that
cannot be sustained. Sukumar suggests that perhaps a third of all India’s
elephants – around 8000 – now live in unsustainable groups. For Sukumar
the present task is to think ahead: to calculate how much more of India’s
woodland is liable to be lost and how many elephants the woods of the future
will be able to support, and then to aim for what is realistic. Desai puts
it another way: ‘I do not care too much how many elephants are left,’ he
says, ‘provided what is left is viable, and properly managed.’

The future may look meagre in statistical terms: perhaps 15 000 elephants
will remain in India with a few reserves, with perhaps as many again in
the rest of Asia, compared to the millions that once roamed over all Asia
and were so prodigally deployed as war machines and traction engines. But
it must be better to aim for a population of 15 000 individuals in India,
that are well looked after, genetically secure, and able to resurge and
readapt when times improve. There is not a lot of time, but it can be done.

Colin Tudge is a freelance science writer. His latest book, The Engineer
in the Garden, on the future of genetics, is published by Jonathan Cape.
This article was researched at a seminar on the Conservation of the Asian
Elephant organised by the Bombay Natural History Society and held at Mudumalai
Wildlife Sanctuary, Tamil Nadu.