African Journal of Environmental Science and Technology Vol. 4(6), pp. 401-411, June, 2010 Available online at http://www.academicjournals.org/AJEST DOI: 10.5897/AJEST09.158 ISSN 1991-637X ©2010 Academic Journals Full Length Research Paper Aerial survey of Elephants (Loxodonta africana africana), other large mammals and human activities in Waza National Park, Cameroon Désiré Foguekem¹ ²*, Martin Ngankam Tchamba¹, Patrick Omondi³ 1WWF Cameroon Program Office, P.O. Box 6776, Yaoundé, Cameroon. 2Department of Animal Biology Faculty of science, University of Yaounde 1, P.O. Box 812 Yaoundé, Cameroon. 3Kenya wildlife Service, P.O. Box 40241, Nairobi, Kenya. Accepted 18 March, 2010 Total aerial count of elephants, other large mammals and human activities in Waza National Park was conducted between 21st and 23rd February 2007. Total counts of elephants and other wildlife species were done and livestock numbers were estimated. A Cessna 206 Stationair six-seater aircraft fitted with GPS was used in navigation, recording survey paths and waypoints. A total of three different herds of 180 and 66 in the park along with a further 250 migrating elephant population towards Kalamaloue National Park were counted. The herds in the park were aggregated around central part of the park along watering point. The consideration of the number of the migrating herd then put the total Waza ecosystem elephant population at 496 individuals. The total number of carcasses recorded was 7 giving a carcass ratio of 2.85%. About 21,002 heads of livestock and over 50 farmlands and human settlement were estimated in the zone abutting the park. This signifies a high level of human pressures at the periphery and thus a high potential for loss of range for the elephants and illegal killing. Key words: Aerial count, elephant, large mammals, human activity, Waza National Park. INTRODUCTION Elephants in Cameroon occur in three distinct bio-geo- the deforestation of the Mandelia Faunal Reserve (Fry, graphical regions, with the Savannah elephants occurring 1970). Yet, there are little accurate estimates of elephant in the Northern Savannah ranges in the Sahelian and populations in the Waza National Park. The lack of Sudanian regions and forest elephants in the Southern accurate information on elephant population is cause for forested area (Tchamba et al., 1997). In 1936, the concern for conservation and management of this northern savanna population was estimated at no more species as in most cases elephants leave protected than 200 individuals, while the Southern forested zone areas where they are relatively protected and roam into was thought to hold between 9,000 and 10, 000 farmland, hunting zones or logging concessions where elephants (Jeannin, 1936). Between the 1940s and the they become very vulnerable to poaching. Elephants 1960s, populations in the Northern savanna reportedly could be used as a flagship species in developing doubled and by 1971, increasing elephant numbers were management decision in and outside protected areas if already cause of concern as elephants were destroying numbers and distribution are well determined. This can Acacia tree woodland in Waza National Park (Corfield only be done through population estimates over time as a and Hamilton, 1971). Most of the increase was asso- means of detecting changes in population number (Craig, ciated to the immigration into Northern Cameroon from 2002). In order that this be done as effectively as possi- Chad, probably resulting from disturbances there such as ble, it is necessary to use method, which is efficient in producing accurate and precise results, which remain comparable over time. Many attempts to estimate elephant population size in *Corresponding author. E-mail: [email protected]. Tel: (237) the Waza National Park had been done. Esser and Van 74179235 or (237) 99852878. Fax: (237) 22214240. Laveieren (1979) estimated 478 elephants; Eijs and 402 Afr. J. Environ. Sci. Technol. Ekobo (1987); Steehouwer and Kouahoue (1989) esti- with Sclerocarya birrea tree savanna, Combretum and Terminalia mated 750 elephants within the Park. An aerial sample shrubs and stands of Hyphaena thebaica; Anogeissus leiocarpus woodland on sandy soil. Lannea humilis open grass savanna with count conducted in the Waza – Logone ecosystem in short annual grasses, sparse trees and stands of Mitragymna 1991 gave an estimate of 1,100 elephants (Tchamba and innermis forming small islands around temporary waterholes. The Elkan, 1995). No aerial total count has previously been Acacia seyal tree savanna on black clay soils which are saturated conducted in the area and, given the disparities in with water in the rainy season. The latter vegetation type is slowly counting methods and the growing length of time since spreading as the area gradually dries out. The Yaéré floodplains is populated with perennial grasses such as Vetiveria nigitana, Oriza the last systematic survey in 1991, it was important to get longistaminata, Echinocloa pyramidalis, E. stagnina and some her- an up to date population estimate. Waza National Park is baceous legumes including Sesbania pachycarpa. Water continues one of the Cameroon’s MIKE (monitoring of illegal killing to be one of the most serious problems for Waza. Recently, impor- of elephant) sites and is believed to hold the largest tant dry season waterholes have been created and managed in the elephant population in Northern Cameroon with high con- floodplain zone. centration of other large mammals, which makes Waza the focus of considerable conservation interest in METHODS Cameroon. Information on elephant numbers and range is important for effective conservation and management Choice of the study design of Africa’s elephants. Since the 1991 survey, information on elephant population size comes from ground counts of Several survey methods are used to census animals in Africa. Foot large mammals that, staff and students of the college of count for small and accessible area, which shows little bias when carefully designed and carried out (Burnham et al., 1980). Vehicle wildlife management of Garoua and the Park manager counts are practicable and give excellent and consistent results in occasionally carried out. Moreover, only small areas of small to medium sized areas. Its use is only limited with the the park surface can be sampled from the ground, con- available road system and may be of poor accuracy for species with sequently, most of the population estimate of elephants a clumped distribution (Jachmann, 1991). The dropping count has been inaccurate. We hypothesized that the elephant method is widely used to estimate elephant densities (Barnes and Jensen, 1987; Fay, 1991). It provides relatively good results for its population in the Waza National Park may be declining cost (Jachmann, 1991), but there are several potential sources of as a result of poaching and illegal activities in the park. error related to deriving the index of abundance and turning this Therefore, the 2007 total aerial count of Waza National index into an estimate of elephant numbers (Barnes, 1993; Park was undertaken with the aim to determine the cur- Tchamba, 1992). rent baseline status of Waza’s elephant population and In the savannah ecosystem, direct aerial count is the recom- map out the threats to this Northern population and their mended method, which has proven its effectiveness for quite long- time ago. It is widely used in South, East and West Africa (Bouché distribution. et al. 2003; Douglas-Hamilton, 1996). Reliable and consistent The following specific questions were addressed: (1) results can be obtained so long as some straightforward precau- What is the current elephant population size and distribu- tions are taken. It covers large area quickly and economically and is tion? (2) What is the number and distribution of elephant the only method for censuring in areas where access on the ground carcasses? (3) What is the distribution and numbers of is difficult or impossible. Its use becomes limited when the other species such as Giraffes, roan antelopes and live- vegetation is so thick that the animals cannot be seen from the air, or the animals concerned are too small (Craig, 1993). stock? And (4) what is the incidences of human activities There are several aerial survey methods, each appropriate to a that may be threatening elephants through protected area different situation. The methods are described well elsewhere encroachment? (Norton-Griffiths, 1978; Gasaway et al. 1986; Craig, 1993; Mbungwa, 1996; Douglas-Hamilton, 1996; Jachmann, 2001). According to Craig (2002) the choice of methods affect accuracy, MATERIALS AND METHOD precision and efficiency, although differing circumstances may demand different choices and one survey may even be made up of Study area areas surveyed by different methods. There are four different approaches: (1) Aerial distance counts require more equipment, Waza national park (Figure 1) is located near Lake Chad in the preparation and analysis than, (2) transect sample count, but may department of Logone and Chari, Northern Province of Cameroon add both precision and accuracy. However, the degree of improve- and lies between 11º00’-11º30’N and 14º30’-14º75’E. It covers an ment is not known and may be slight for elephants, which does not area of approximately 170 000 ha with an average altitude of 300 – justify the investment of using it (Craig, 2002). (3) Total counts are 320 m, rising to 500 m on the rocky outcrops around Waza village. the most precise and accurate, as long as search-rate standard are The park lies in the Chad depression in an area of low relief with no adhered to. However, there are seldom the resources to carry them permanent rivers. Soils are mainly ferruginous tropical with various out and they should only be considered when the survey area is catenas, hydromorphic soils and vertisols. The climate of the region less than 100 km². Transect sample counts are recommended is semi-arid, with a dry season extending from October to May.