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THE NILE CROCODILE

COMMON NAMES:
Nile crocodile, Mamba, Garwe, Ngwenya

DISTRIBUTION:
Angola, Benin, Botswana, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Congo, Egypt, Ethiopia, Equatorial Guinea, Gabon, Gambia, Ghana, Guinea, Guinea Bissau, Ivory Coast, Kenya, Liberia, Madagascar, Malawi, Mali, Mozambique, Mauritania, Namibia, Niger, Nigeria, Rwanda, Senegal, Sierra Leone, Somalia, South Africa, Sudan, Swaziland, Tanzania, Togo, Uganda, Zaire, Zambia, Zimbabwe.

HABITAT:
Wide habitat preferences, reflecting their success and distribution- e.g. lakes, rivers, freshwater swamps, brackish water. Nile crocodiles modify their habitat by digging dens (usually with their snouts and feet) into which they retreat from adverse conditions such as temperature extremes.

STATUS:
IUCN-International Union of Conservation of Nature (LOW RISK, LEAST CONCERN)
Estimated wild population: 250,000 to 500,000
Summary: Wide distribution coupled with healthy populations and successful management

APPEARANCE:
Generally, it is a large crocodilian, averaging 15ft. in length but reportedly reaching 18ft. There are two known population of dwarf Nile crocodiles living on the extreme limits of the species' range, in Mali and even the Sahara Desert! Due to suboptimal conditions, adults average between 6-9ft. Juveniles are dark olive brown with black cross-banding on the tail and body.

DIET:
Although the juveniles are generally restricted to eating small aquatic invertebrates and insects, they soon move onto larger vertebrates (fish, amphibians and reptiles). Adults, however, can potentially take a wide range of large vertebrates, including antelope, buffalo, young hippos, and large cats. Fish and smaller vertebrates often form the greatest part of their diet, however. They have a reputation as being man-eaters, and probably kill more people than all other crocodilian species combined. Along with hippos and lions, crocodiles account for perhaps a few hundred deaths and disappearances each year, although exact figures are very hard to verify. They have a rather well-known relationship with several species of birds which are reputed to pick pieces of meat from between the teeth of the crocodiles as they gape - the birds gain a meal, the crocodiles have their teeth cleaned of scraps they could not eat themselves.

BREEDING:
This species digs hole nests up to 2ft deep and deep into the sandy bank while keeping a short distance from the waters edge., and usually close to other nests. Females reach sexual maturity around 7ft. and males at around 9ft. Females lay around 40 to 60 eggs in the nest. Females also remain near the nest at all times. Incubation time averages 80 to 90 days, after which females open the nest and carry the juveniles to the water. Both males and females have been reported to assist hatching by gently cracking open eggs between their tongue and upper palate. As with many crocodilians, older juveniles tend to stay away from older, more territorial animals.

CONSERVATION:
When considering its total distribution and status, the Nile crocodile is not considered seriously endangered. Extensive population surveys in some areas have contributed to sustainable-yield management programs, mainly in southern and eastern African countries.

After a population decline around the middle of the century due to over-hunting, legal protection has resulted in significant recoveries in several areas, and large populations can now be found in Botswana, Ethiopia, Kenya, Zambia and Zimbabwe. The skin from this species is considered to be a 'classic' skin, in that high-quality leather is obtainable without blemish-causing osteoderms reducing its value. Commercial utilisation is widespread, therefore, and many successful management programs have been established (e.g. Zimbabwe, South Africa). These have mainly been set up in conjunction with CITES, with the emphasis being placed upon ranching programs.

Further conservation goals should include detailed surveys in western and central African countries, and the nurturing of newly-established management programs. Ecological research into population dynamics should also provide valuable information for sustainable-yield programs.