| dc.description.abstract | The ecology and behaviour of maasai Mara Game Reserve
rhinoceros was studied from May 1971 to August 1972.
At the end of August 1972, the entire Mara rhino
population consisted of 10 animals of which 73% were
adults and 27% were immature animals which accompanied
their mothers. The adult population consisted of 54%
males and 46% females.
The density of black rhino in the Mara Game reserve
is 0.07/km2 considering the entire reserve area (1530 km2)
and 0.14/km2 considering the area occupied by rhinos
2 (749 km). The recorded highest individual distribution
area density was 0.?3/km2. There was no noticeable
difference between the mean densities obtained from the
ground and aerial count though an aerial count was not
carried out in the Triangle area.
In the entire study area, 13 rhino distribution areas
were known. Bach of the 13 distribution areas had rhinos
which associated with each other but individuals from one
distribution area were never observed associating with
individuals from another distribution area. The
movement of rhinos out of the reserve was negligible.
Rhinos were distributed over the plains, grassland
with scattered trees, slopes of hills and thickets
along river courses. Rhinos appeared to prefer areas
with abundant cover for shelter, food, water, and with
absence of human and domestic animals.
The sex ratio of adult females: adult males was 1:1.1
and for immature females: immature males was 1:3.2. Out
of 28 immature rhinos 11 were not sexed due to some
difficulties hence the sex ratio for immature rhinos
cannot be interpreted with confidence.
The entire rhino population was divided into four
age classes. Age class I representing individual rhinos
from 0 - 1 year old, class II from 1 - 2 years old,
class III from 2 - 4 years old and class IV over 4 years
old.
Although rhinos are known to mate at any time of
the year, individuals of the Mara population were
observed mating during the period between September
and April. Usually, this is the hot period of the year.
Mortality of adults and calves as found to be
very low. Only one adult rhino died during the study
period and none of the calves died.
On social organization, black rhinos are solitary
animals but occasionally, adult males and adult females
can be observed together particularly during the feed.ing
hours or during mating periods. Sub-adult rhinos are
solitary but they can sometimes be seen joining their
mother and in the case of females, joining adult males.
The only form of organization which is rather permanent
is mother-calf unit which is frequently observed until
the time when calf leaves the mother. On some
occasions mother-calf unit is observed associated with
single adult male.
rhino's pattern of association strengthens bond
between mother and its calf and weakens the bond between
adult individual rhinos. Group defence from enemies is
minimal and individual rhino is left to defend itself
alone. This pattern of association, on the other hand,
makes it difficult to locate rhinos in the wilderness
other than the times when they are on open areas
carrying out their other daily activities.
Rhinos have home ranges which are generally shared
by males or females in the adjacent home range. The
size of home range is dependent on available food,
cover, ater, main activities and domesticated animals.
The home range size varied with social units. Females
with calves had lar cr home ranges than single females
or single males. Females ith calves move a lot looking
for palatable herbs and shrubs. movements of rhinos
within their home ranges, either daily or seasonal,
causes a considerable degree of home range overlapping.
No indication of territorial behaviour was observed.
Because rhino tend to remain attached to some particular
area, the density can be quite hi h in some areas and
less in other areas depending on the number of individual
rhinos occupying these areas. In the game reserves or
national parks the rhino attachment to particular
areas makes it possible for ran ers to have a rough
estimate of areas to the tourists. Also this
attachment to particular area limits the degree of
association with other rhinos other than its neighbours.
Rhinos were also observed association ith the buffalo,
giraffe, topi and wildebeest living within rhinos home
ranges.
Black rhino in Mara were observed feeding on
varieties of plants with preference for Solanum incanum
and Acacia species. About 70 different plants species
;
from 30 different botanical families ere recorded.
During the rainy periods a variety of palatable herb are
easily available and it is during these periods that
rhinos were observed selecting a wide variety of herbs
and shrubs. However, during the dry period most of the
herbs and shrubs dry up and climax of shortage of food is
observed during the burning period which normally occurs
during the dry period.
It was observed that rhino's pattern of food
selection is dependent partly on relative density and
relative frequency of plant species used. Rhinos were
observed feeding mainly in open grass and scrub with
scattered trees habitats. These two habitats mainly carry
most of rhino's food.
Rhinos in Mara were observed to feed mainly on
regenerating vegetation. Branches with leaves, and
branches with leaves and inflorescences were mainly eaten.
A portion of plant ranging from 7 to 26 cm is mostly
swallowed by rhino. In some cases leafless remnants of
plants were found uprooted.
Observations indicated two feeding peaks within
twelve hours'of the daylight. One feeding peak is in
the morning and the other in the afternoon. However, other
minor activities may be observed during the feeding peaks.
here i no competition for food ith other animals.
~ild animals using the sa e plants used by rhinos have
different feeding levels. Rhinos in Mara were observed
to be mainly group~ feeders.
Rhinos were observed to visit salt licks in
distribution area A. Other animal species like topi and
buffalo were also observed in this salt lick places.
Salt lick places contained odium, magnesium, potassium
and calcium.
Rhinos were observed drinking water mainly from
sunset or just after the sunset. Ho ever, there is no
doubt that they also drink early in morning or spend most
of their night time near the water places because they
were mostly located in the morning near the water places
walking to their feeding rounds.
mating was observed mainly during the period from
September to April. However, though no record was made,
rhino can mate at any time of the year.
allowing is mainly limited to the rainwater pans or
standing water along the seasonal streams or rivers.
alloing takes place during mid-day which is normally
the hot part of the day. However, wallowing activities
ere frequently observed during the wet days rather than
during dry periods. This is probably due to availability
of water in the rainwater pans. After alloin~ rhinos
were observed rubbin their bodies against a tree, tree
branch or termite mound.
Rhino maintain dung piles. Some of the dung piles
are along tracks frequently used by the rhinos to the
water places or to feeding areas. Over 90% of dung
observed was scraped. Dung piles were aleo observed
being shared and tne"degree of sharing dun piles may
depend on how often the part of the home range where
the dung piles are located is used by another rhino.
rhinos have no definite urinals and were not observed
defecating and urinating simultaneously.
rhinos normally walk as observed during the feeding
hours. However, when disturbed they can run at a speed
of 60 km/h. Then running females with calves are
followed closely behind by their calves but sometimes,
though rarely, calves can be observed leading their
mothers into sheltering places.
Rhinos were observed resting during the mid-day
if they were not wallowing. Rhinos were observed lying
down under a tree shade or resting while standing next
to a tree which provided shade.
Rhinos reaction to strangers reveal that a rather
small number of tendencies are involved in varying
proportions. These tendenciea are curiosity, fear, anger
and inertia.
A number of other lines of possible res arch are
suggested. | en |
