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Serval kitten
courtesy of Jennifer Quincy
Description and Behavior
The
serval
is well adapted to hunting small prey in long grass: its
legs are slim and relatively long, and shoulder height is
about 0.6 m. Its neck is also elongated, its head is small
and delicate, and its ears are tall. The auditory
bullae
are correspondingly well-developed, making up about 22% of
skull length (Skinner
and Smithers 1990).
Males weigh 9-18 kg (averaging 11-13 kg), and females 9-13
kg, (averaging 9.7-11 kg:
Smithers 1971,
Kingdon 1977, Smithers 1978).
Coat color is pale yellow, and is marked with solid black
spots along the sides and bars on the neck and shoulders.
Although 17
subspecies are listed by Allen (1939),
their validity is doubtful (see Appendix I).
Smithers
(1978)
examined specimens from one locality in southern Africa and
found external characters among them, which had been used to
designate six different subspecies within the sub region.
Servals
from West Africa most frequently show a pattern mutation
of small speckled spots -- these so-called
servaline
 
were considered
a separate species (Felis
brachyura Wagner, 1841)
until Pocock
(1917a)
demonstrated that the speckled form was a
serval
morph. Black
servals have
been widely recorded (Shortridge
1934, York 1973, Guggisberg 1975).
DK EYE WITNESS CAT 1995
The heliotype of
L.
serval
was taken near the Cape of Good Hope, but the
serval
now appears to have been extirpated from the entire southern
coastal belt of South Africa and most of Cape province (Skead
1980, Stuart 1985)
-- although M.
Bowland
(in litt.
1993)
notes an unconfirmed report from a farmer at George, midway
between Cape Town and Port Elizabeth.
Small mammals,
especially rodents, are the
serval’s
main prey. Larger rodents are preferred, particularly
vlei
(swamp) rats (Smithers
and Wilson 1979, Geertsema 1985, Bowland 1990),
and also
Nile
rats (Geertsema
1976, 1985).
Smaller mice are of secondary importance (Smithers
and Wilson 1979, Geertsema 1985, Bowland 1990).
Up to 12 mice were found in one
serval
stomach from Zimbabwe (Smithers
1978).
Birds, reptiles, fish and insects are also taken, although
infrequently when rodents are abundant (Geertsema
1985, Bowland 1990).
Geertsema
(1985)
observed one young male
serval,
on a moonlit night, rush into open water to seize one of a
group of feeding flamingos.
Geertsema
(1985)
also found frogs to be a particularly favorite prey item,
with remains occurring in 77% of 56 scats. She saw another
young male eat at least 28 frogs in one three-hour period.
Servals
do not generally take larger prey as does the caracal.
Single animals have only rarely been observed to kill
duikers and fawns of the smaller antelope species (Rahm
1966, de Pienaar 1969, York 1973).
The detailed studies by
Geertsema
(1985:
Ngorongoro
Conservation Area, Tanzania) and
Bowland
(1990:
Natal province farmland, South Africa) did not record any
instances of
servals
taking mammalian prey larger than rodents.
Ecology
The
serval
locates prey in tall grass or reeds primarily by hearing. It
makes a characteristic high leap as it pounces on a prey
animal, striking it on impact to prevent escape in thick
vegetation. A single pounce may span 1-4 meters and may be
over a meter high (Geertsema
1985).
Another type of leap is vertical: birds and insects are
seized from the air by "clapping" the front paws together (Smithers
1978) or
striking with a downward blow (Leyhausen
1979).
Geertsema’s
(1985)
four-year study in the
Ngorongoro
Crater is the most detailed investigation to date of
serval
ecology. She found them to be largely crepuscular, resting
in mid-day and occasionally at night. Females with kittens
increase diurnal hunting activity.
Servals
on farmland in South Africa’s Natal province were
predominantly nocturnal, possibly a response to human
disturbance (Bowland
1990).
Through continuous observations (when possible - although
the study animals were habituated, they were not
radio-collared),
Geertsema
(1985)
found that adult males, adult females and sub-adults spend
about 25% of each 24-hour period traveling and hunting. On
average,
Ngorongoro
servals
killed about 16 times within this period. Independent
sub-adults killed more frequently than adults, but took
smaller prey with a lower energetic return. From nearly
2,000 observations of pounces,
Geertsema
(1985)
found
serval-hunting
success to average 49%, with no significant difference
between day and moonlit night. After giving birth to
kittens, one female increased her success to 62% from 48%.
Titan
Biology
Reproductive Season:
(W) A
seasonal, but birth peaks appear to be correlated with wet
seasons, when prey densities are at their highest due to new
vegetative growth (Kingdon
1977, Smithers 1978).
Geertsema
(1985)
suggests that a peak occurs in the mid- to late dry season
in the
Ngorongoro
Crater, so that post-rains high prey density coincides with
the raising of older but still dependent kittens.
Estrus (C):
4 days
(n=1:
Mellen 1989)
Gestation (C):
73 days
(n=15; range 70-79) (Stuart
and Wilson 1988)
Litter Size:
(W):
2.5 (n=7;
range 1-3) (Smithers
1978);
(C):
1.96
(n=20:
Skinner and Smithers 1990);
2.45+0.21 (n=14:
Mellen 1989);
range 1-5 (Stuart and Wilson 1988)
Age at
Independence:
(W) 6-8
months. Newly independent juveniles, tolerated by their
mothers, may circulate within their natal range for periods
up to and over a year (Geertsema
1985)
Age at Sexual
Maturity:
(C) 18-24
months (P.
Andrews in litt. 1993)
Longevity:
(C) up to
19 years (Green
1991)
Habitat and Distribution
In Sub-Saharan Africa,
servals
are found in well-watered savannah long-grass environments (Shortridge
1934, Rosevear 1974, Smithers 1978),
and are particularly associated with reed beds and other
riparian vegetation types (Geertsema
1985, Bowland 1990).
This association with water sources means that their
distribution is strongly localized over a wide area and
within a variety of habitat types . They range up into
alpine grasslands (Ansell
and Dowsett 1988),
up to 3,200 m in Ethiopia (Yalden
et al. 1980)
and 3,800 m in Kenya (York
1973).
Servals
can penetrate dense forest along waterways and through
grassy patches, but are absent from the rainforests of
Central Africa. A few records from arid parts of
south-western Africa, Ethiopia and Somalia indicate that
servals
will occasionally make use of sub-optimal habitats (Shortridge
1934, Yalden et al. 1980, Stuart and Wilson 1988, A.
Simonetta in litt. 1992).
In North Africa,
relict populations may still be found in humid scrub and
mixed woodlands of Morocco’s Atlas Mountains (Lambert
1966) and
northern Tunisia and Algeria (Gouttenoire
1954, De Smet 1989).
The last confirmed record from Algeria is of an animal
killed by a French hunter in 1936 in
Arzew
(north-west coast), said to be the last in the area. There
have been scattered reports of
serval
occurrence throughout northern Algeria during the 1980s, but
zoologists have not been able to confirm them (De
Smet 1989, K. de Smet in litt. 1993).
Surviving animals are likely to have been isolated from
sub-Saharan populations for at least 6-7,000 years (Swift
1975).
Population Status
Global:
Category
4
Regional
(sub-Saharan Africa):
Category 3
Regional
(North Africa):
Category 2(A)
IUCN:
Not
Listed
Smithers
(1978)
reviewed the
serval’s
distribution and concluded that its range has remained
largely intact, shrinking only in the extreme north and
south due to habitat loss in the wake of increasing
urbanization and changes in land use (C.
Stuart in litt. 1993).
Possibly
servals were
never very numerous in North Africa, and water sources in
the region are likely to be focal points of human use and
settlement. However,
servals
are highly tolerant of agricultural development, which
fosters increased rodent densities, as long as there is
sufficient water and shelter available (Bowland
1990).
Kingdon
(1977)
notes that the
serval
has adapted well to the cultivation-fallow mosaic that is
widespread over the moister regions of Africa. Degradation
of forests to savannah in West Africa probably favors the
species.
Geertsema
(1985)
found minimum home ranges in
Ngorongoro
to be 11.6 km2
for one adult male and 9.5 km2
for one adult female over four years. The male’s home range
overlapped those of at least two adult females, while the
ranges of three adult females showed minimal overlap.
Bowland
(1990)
found larger home ranges for
servals
on South African ranchland: 16-20 km2
for two adult females and 31.5 km2
for one male, monitored for 4-5 months during the spring and
summer.
Protection Status
Protection
Status: CITES Appendix II
National
Legislation:
Not protected over most of its range
Hunting
prohibited:
Algeria, Botswana, Congo, Kenya, Liberia, Mozambique,
Nigeria, Rwanda, South Africa (Cape province only)
Hunting
regulated:
Angola, Burkina Faso, Central African Republic, Ghana,
Malawi, Senegal, Sierra Leone, Somalia, Tanzania, Togo,
Zaire, Zambia
No legal
protection:
Benin, Cameroon, Ethiopia, Gabon, Gambia, Guinea Bissau,
Ivory Coast, Lesotho, Malawi, Mauritania, Morocco, Namibia,
Niger, South Africa, Sudan, Swaziland, Tunisia, Uganda,
Zimbabwe
No
information:
Burundi, Chad, Djibouti, Guinea
(IUCN
Environmental Law Centre 1986, Smithers 1986, Hecketsweiler
1988)
Principal Threats
Wetland conservation is the key to
serval
conservation. Wetlands harbor comparatively high rodent
densities compared to other habitat types, and form the core
areas of
serval
home ranges (Geertsema
1985, Bowland 1990).
Of secondary importance is degradation of grasslands through
annual burning followed by over-grazing by domestic
hoofstock,
leading to reduced abundance of small mammals (F.
Hurst in litt. 1991, Rowe-Rowe 1992).
Trade in
serval
pelts has been reported from many countries (Yalden
et al. 1980, Sayer and Green 1984, Myers 1986, Cunningham
and Zondi 1991; L. Gadsby, F. Hurst in litt. 1991, E. Abe in
litt. 1993);
they are frequently marketed as "cheetah" or "leopard".
While the scale of the harvest and its effect upon
populations is difficult to judge, the pelt trade appears to
be primarily domestic (especially for ceremonial or
medicinal purposes) or tourist-oriented, rather than
international commercial exports (WCMC
unpubl. data;
see Table 1 in Part II Chapter 4). The
serval’s
localized distribution around water sources may increase its
vulnerability to hunting; it will also climb a tree when
chased by hounds (Stuart
1985).
Servals
occasionally kill domestic poultry and only rarely young
livestock (sheep and goats): studies of their diet in
farming areas in Zimbabwe (Smithers
1978) and
South Africa (Lawson
1987)
found no evidence that predation was a problem.
Bowland
(1990)
pointed out that problem animals, which raid chicken coops,
could be easily live-trapped for translocation. Although 17%
of Namibian farmers who indicated that
servals
were present on their land reported livestock predation,
none took any control measures (legally permissible),
indicating that the problem is not serious. For comparison,
36% of the farmers reporting stock predation by African
wildcats took control measures (Joubert
et al. 1982).
The serval’s
preference for rodent prey should actually benefit farmers:
Geertsema
(1985)
calculated that an adult
serval
would eat some 4,000 rodents a year.
Serval
kitten
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