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Crocodiles
The Crocodilian Hotel has recently
aquired two beautiful baby Crocodiles. Below
you will find more information on these
beautiful animals.
The Nile Crocodile
History and Evolution
Crocodilians
belong to the great group of archosaurs
or "ruling reptiles", so called
because for 150 million years they have
ruled the world. This group also included
the extinct thecodonts, the dinosaurs, the
pterosaurs or flying reptiles and the ancestors
of the birds (Benton, 1982). Crocodilians
of the most advanced kind, the Eusuchians,
first appeared some 140 to 65 million years
ago, and the crocodilians of today all belong
to this suborder. There are some 22 species
found throughout the world today, belonging
to Family Crocodylidae which is further
divided into 3 subfamilies: a) Crocodylinae,
b) the Alligatorinae and c) the Gavialinae.
Distribution and Habitat
Below: Distribution of Nile crocodiles in
Africa (indicated in yellow).
Crocodilians and Alligatorians are found
between the latitudes of cancer (23.5°
north) and Capricorn (23.5° south),
in the rivers and lakes of South America,
Africa, Asia and Australia. The Nile crocodile,
Crocodylus niloticus, is one of 3 species
of crocodiles inhabiting the African continent.
It is widespread throughout the continent,
south of the Sahara Desert, but is absent
from much of the extreme south and southwest.
Nile crocodiles have wide habitat preferences,
reflecting their success and distribution
as a species. They are present in a variety
of wetland habitats, including rivers, lakes,
swamps and brackish water. They are also
found in coastal areas of west and southern
Africa.
Status in Africa
In southern and eastern Africa a number
of surveys for Nile crocodiles have been
conducted in recent years, and information
on crocodile status is average. More recent
survey information is available for: Tanzania
(Games and Severre, 1992), South Africa
(Blake and Jacobsen, 1992) and Kenya (Soorae,
1994), while Hutton and Games (1992) provide
a collection of surveys for Botswana, Kenya,
Madagascar, Malawi, Mozambique and Zambia
conducted between 1981 and 1987. However,
for the majority of African countries (25
out of 39) there is inadequate information
on the status of Nile crocodile populations
(Ross, 1998). Moreover, many of the surveys
that have been carried out have been inconsistent.
As with many of the other, large commercially
valuable crocodilian species, hide hunting
in the 1940's -1960's resulted in dramatic
declines in Nile crocodile populations throughout
most of its range (Cott, 1961; Parker and
Watson, 1970). As a result, the Nile crocodile
was listed at the Washington plenipotentiary
conference in 1973 and was already on Appendix
1 of CITES before it came into force in
1975 (Hutton, 1992). However, protection
by national laws and international regulations
have resulted in a recovery in many parts
of the species range (Ross, 1998). By 1985,
due to the crocodiles recovery, expanding
human populations and the high value placed
on crocodile skin, pressure to recommence
exploitation induced CITES to introduce
a quota scheme under which a limited number
of wild taken crocodile skins could be exported
every year. Commercial utilization, including
both farming and ranching, is now widespread
and many successful management programmes
have been established. However, although
various crocodilian management programmes
exist today, wildlife management is often
very localized and a programme must therefore
be tailored specifically to the context
in which it is expected to work. Biological
and social problems, particularly in Africa,
must also be taken into consideration.
References
Benton, M. J. 1982. The Diapside: Revolution
in Reptile relationships. Nature 296:306-307.
Blake, D. K. and N. Jacobsen. 1992. The
conservation status of the Nile crocodile
(Crocodylus niloticus) in South Africa.
In: Conservation and utilization of the
Nile crocodile in Southern Africa. Handbook
on crocodile farming. Smith, G. A. and J.
M. Marais (eds).
Cott, H. B. 1961. Scientific results of
an enquiry into the ecology and economic
status of the Nile crocodile (Crocodylus
niloticus) in Uganda and Northern Rhodesia.
Transactions of the Zoological Society of
London 29: 211-356.
Games, I. and E. Severre. 1992. The status
and distribution of crocodiles in Tanzania.
In: Crocodiles. Proceedings of the 11th
Working meeting of the Crocodile Specialist
Group. Vol 1: 119-137. IUCN, Gland, Switzerland.
Hutton, J. M. 1992. The CITES Nile Crocodile
project. A publication of the Secretariat
of the Convention on International Trade
in Endangered Species of Wild Fauna and
Flora, Lausanna, Switzerland.
Parker, I. S. C. and R. M. Watson. 1970.
Crocodile distribution and status in the
major waters of western and central Uganda
in 1969. East African Wildlife Jnl 8: 85-103.
Ross, J. P. 1998. Crocodiles. Status survey
and conservation action plan. 2nd edition.
IUCN/SSC Crocodile Specialist Group. IUCN,
Gland, Switzerland.
Soorae, P. S. 1994. Nile crocodile in Kenya.
Crocodile Specialist Group Newsletter 13(4):
5-6.
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