200
number unknown
650, estimated by P. Flizot, `inspecteur de chasse'
number unknown
The highest total of 15,000 in 1980 is in fact the top of the curve reported by IUCN in that decade.
The total of all subspecies of black rhino combined have been estimated at 100.000 in 1960 (CITES 1962).
The total of all subspecies of black rhino combined have been estimated at a million individuals in the mid 19th century
number unknown
110
15-50
No information about the existence of rhinos in Tchad has been verified since 1987 (Pfeffer and Temporal), except a few individuals on the Cameroon border.
Early 1996 a ranger killed the last rhinoceros in the south of the Parc de la B?nou?: although implicated by villagers and colleagues, he remains in his post without punishment.
35
20
10
Distribution in 1980 and 1998
During the last 10 years, 1987-1999, established localities are situated between 7.30 and 9 degrees north in the eastern part of Northern province, and between 7.30 and 8.30 deg. In the west. This is a reduction in the south of some 100 km compared to observations in early 20th century. This is coupled with a progressive and constant fragmentation of the habitat in North Cameroon. Since early 1980's the population is broken into two groups by the isolation of the animals in Faro, then poaching has reduced the animals into 10 groups in 1996 and 7 in 1997, and again 6 in late 1998 when some individuals may not have been localised due to poor weather conditions. Many localities were not mentioned earlier, it is not possible if these are new locations or if the animals just hadn't been seen there. Since late 1995 there have been no rhinos in the national parks (except maybe Faro), all live in hunting zones leased to private game hunting licensees.
The evolution of the numbers of Diceros bicornis longipes in Central and West Africa does not follow the curve for the entire species. An intense period of destruction at the start of the 20th century wiped out the subspecies in West Africa, Bouna in Ivory Coast in 1905, and brought it to the brink of extinction in Central Africa, where however still 400 were thought to exist in Nord Cameroun, North Central African Republic and southern Tchad. After 25 years of strenouous efforts, scientists in central Africa could report an increase in numbers and an extension of the range towards places where the animal had disappeared. Numbers of 1000 individuals were mentioned in 1957, of which 300 (or 450) were listed for Cameroon, an annual increase of 3 %.. The increase continued to numbers of 2000 in 1960 to 3000 in 1980, an increase of 4,5 to 6 % per annum.
The evolution of the numbers of Diceros bicornis longipes in Central and West Africa does not follow the curve for the entire species. An intense period of destruction at the start of the 20th century wiped out the subspecies in West Africa, Bouna and Ivory Coast in 1905, and brought it to the brink of extinction in Central Africa, where however still 400 were thought to exist in Nord Cameroun, North Central African Republic and southern Tchad. After 25 years of strenouous efforts, scientists in central Africa could report an increase in numbers and an extension of the range towards places where the animal had disappeared. Numbers of 1000 individuals were mentioned in 1957, of which 300 (or 450) were listed for Cameroon, an annual increase of 3 %.. The increase continued to numbers of 2000 in 1960 to 3000 in 1980, an increase of 4,5 to 6 % per annum. The status of the subspecies changed qickly. Some numbers reported in the 1980's lacked coherence and seemed to reflect some disinterest in the subspecies. The numbers mentioned by IUCN, between 320 and 3000, for central Africa shows a very mediocre knowledge of these animals. In 1980, the number was estimated at an absolute minimum of 100 (Pfeffer, unpublished) for Cameroon, but that author is convinced that the actual number probably was more than double.In 1990, after continued poaching, there were no more than 50 rhinos. In 1991, 30 individuals are confirmed to exist (Planton, unpublished). As populations in CAR and Tchad were wiped out in the 1980's, Cameroon was the only country with a viable rhino population. The institutional capacity and the political will of the country were much reduced. No aid was requested, nor proposed, despite the urgency of the situation. The scientific community added to the general confusion. The numbers were much under-estimated and the survival chances were considered very weak, while nobody acted on the report of Alers, and by 1987 the subspecies was considered extinct genetically.
In the 1980's, Cameroon was earnest in trying to improve the conservation status of the fauna. A formal request for assistance was formulated by the ministry in December 1980, but the response from WWF International in October 1981 was that after evaluation of the priorities of IUCN, no funds were available. This lax attitude continued during the 1980's. A cooperation of those involved ended with two requests for assistance by the Cameroon government (in 1991 and 1992) and by the taking into consideration by the French Ministry of Cooperation aid for a project directed mainly to the rhinoceros. However, these funds were released as part of a larger environmental programme, the Project Biodiversit? Nord. The following actions were taken: 1. The distribution area in North Cameroon was regularly visited from 1987 to 1990 as part of the Pan African Campagne against Bovine Fever, and 1991-1995 to obtain more information. More intensive and specific investigations were done in 1996, 1997, 1998 as part of the FAC project Biodiversit? Nord. WWF Cameroon on the basis of these investigations keeps a regular update of the information sicne 1991, but it has been decided that sensitive information is not to be disclosed. 2. In 1993, a sample from a recently poached animal was sent to two laboratories specialised in rhinoceros genetics (Kleberg Genetic Chair, Centre for Reproduction of Endangered Species, San Diego, and Department of Chemical Pathology, University of Cape Town), but they have not yet been investigated. 3. A second tissue sample was sent in July 1996 under the best circumstances to a laboratory in South Africa for DNA sequencing for systematic purposes. Although the analysis only had one individual to work with, the results clearly indicated a marked difference between longipes and the other black rhino subspecies. At the moment, two alleles exist in longipes which have not been found in any other black rhino subspecies (Harley, communications of 1988 and 1999). 4. In the initial programme, it was decided to equip 10 rhinos with radio transmitters. One radio was placed in a female with the help of Peter Morkel, but the animal was poached after 1 ? months. The trial was lengthy, and was decided due to the presence of the radio in the horn. The authorities then decided to abolish this part of the project.
The evolution of the numbers of Diceros bicornis longipes in Central and West Africa does not follow the curve for the entire species. An intense period of destruction at the start of the 20th century wiped out the subspecies in West Africa, and brought it to the brink of extinction in Central Africa, where however still 400 were thought to exist in Nord Cameroun, North Central African Republic and southern Tchad. After 25 years of strenouous efforts, scientists in central Africa could report an increase in numbers and an extension of the range towards places where the animal had disappeared. Numbers of 1000 individuals were mentioned in 1957, of which 300 (or 450) were listed for Cameroon, an annual increase of 3 %.. The increase continued to numbers of 2000 in 1960 to 3000 in 1980, an increase of 4,5 to 6 % per annum. In the early 1990's, a systematic poaching of rhinos wipes out the animal in a few years time. Since early 1985, none have been sighted.
Extinct in 1905 in Bouna, [9.16 N, 3.0 W, N.W. Ivory Coast, just east of Komoe NP], see Jeannin 1951.
Formerly black rhinos lived in northern Garoua province in vegetations dominated by Acacia (mostly A. hockii and A. senegal). This is the kind of terrain seen to be most suitable to rhinos by anglophone researchers. Today the rhino live in an area of wooded savannah, in the sudanese or soudanese-guinea zone, which is dominated by populations of Isoberlinia, Terminalia, Combretum, Acacia, Burkea, Gardenia, Piliostigma and parts with Anogeissus. Favourite habitats have valleys, most often near to slopes, watered by small streams, often seasonal, which have several permanent water holes during the dry season. Rhinos are never far from water. They usually drink every night or earky morning, and they love to wallow in mud during the morning hours. They also frequent salt licks. Then they eat and then rest to hide from the heat, often under trees or in swampy places until late afternoon if they are not disturbed.
In the present situation (very few animals, maybe 10-15 spread over a region of 25.000 km? ) it is hard to advance a number for possible rhino density. In the past it seems that there was one adult rhino per 10-20 km? according to the quality of the habitat.
Cameroon. The rhino's attraction for humid habitat allows them to find a varied diet, even in the dry season. Despite few observations in the foeld, 30 different plants are identified. Among the plants there are numerous leguminous plants, the fruit of Kigelia africana, also Vernonia, Hoslundia, Sarcocephalus latifolius, high plants like Echinochloa, and many small herbs. When they move away from waterholes, they usually select branches of Acacia ataxacantha, A. polyacantha, A. seyal, A. hockii, Gardenia aquala, G. erubescens, Annona senegalensis, Piliostigma thoningii, Vitellaria paradoxa.
The natural home ranges observed usually are greater than 200 km? per animal, while many home ranges can partially overlap. In the absence of disturbances, movements seem to be more important in the dry season - fresh traces followed over distances of 30-40 km per day, than in the wet season - distances always less than 10 km. Also seasonal movements of 100 km and over have been observed. This seems to permit contact between individuals which would seem to be isolated if one would not pay attention to the entire annual cycle.
The characteristics of the environment where the rhinos live make direct observations very difficult. It is not strange to be within a few metres of a rhino without being able to see it. Idenfification of traces and footprints help to estimate numbers, the home range, and the principal habitats.
Cameroon. The rhino's attraction for humid habitat allows them to find a varied diet, even in the dry season. Despite few observations in the foeld, 30 different plants are identified. Among the plants there are numerous leguminous plants, the fruit of Kigelia africana, also Vernonia, Hoslundia, Sarcocephalus latifolius, high plants like Echinochloa, and many small herbs. When they move away from waterholes, they usually select branches of Acacia ataxacantha, A. polyacantha, A. seyal, A. hockii, Gardenia aquala, G. erubescens, Annona senegalensis, Piliostigma thoningii, Vitellaria paradoxa.
They usually drink every night or early morning, and they love to wallow in mud during the morning hours. They also frequent salt licks. Then they eat and then rest to hide from the heat, often under trees or in swampy places until late afternoon if they are not disturbed.
A second tissue sample was sent in July 1996 under the best circumstances to a laboratory in South Africa for DNA sequencing for systematic purposes. Although the analysis only had one individual to work with, the results clearly indicated a marked difference between longipes and the other black rhino subspecies. At the moment, two alleles exist in longipes which have not been found in any other black rhino subspecies (Harley, communications of 1988 and 1999).
Cameroon. A second tissue sample was sent in July 1996 under the best circumstances to a laboratory in South Africa for DNA sequencing for systematic purposes. Although the analysis only had one individual to work with, the results clearly indicated a marked difference between longipes and the other black rhino subspecies. At the moment, two alleles exist in longipes which have not been found in any other black rhino subspecies (Harley, communications of 1988 and 1999).
