Human Pressure Threaten Swayne's Hartebeest to Point of Local
Total Page：16
File Type：pdf, Size：1020Kb
Research Article Volume 8:1,2020 Journal of Biodiversity and Endangered DOI: 10.24105/2332-2543.2020.8.239 Species ISSN: 2332-2543 Open Access Human Pressure Threaten Swayne’s Hartebeest to Point of Local Extinction from the Savannah Plains of Nech Sar National Park, South Rift Valley, Ethiopia Simon Shibru1*, Karen Vancampenhout2, Jozef Deckers2 and Herwig Leirs3 1Department of Biology, Arba Minch University, Arba Minch, Ethiopia 2Department of Earth and Environmental Sciences, Katholieke Universiteit Leuven, Celestijnenlaan 200E, B-3001 Leuven, Belgium 3Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium Abstract We investigated the population size of the endemic and endangered Swayne’s Hartebeest (Alcelaphus buselaphus swaynei) in Nech Sar National Park from 2012 to 2014 and document the major threats why the species is on the verge of local extinction. The park was once known for its abundant density of Swayne’s Hartebeest. We used direct total count methods for the census. We administered semi-structured interviews and open-ended questionnaires with senior scouts who are a member of the local communities. Historical records were obtained to evaluate the population trends of the animals since 1974. The density of the animal decreased from 65 in 1974 to 1 individual per 100 km2 in 2014 with a decline of 98.5% in the past 40 years. The respondents agreed that the conservation status of the park was in its worst condition ever now with only 2 Swayne’s Hartebeest left, with a rapid decline from 4 individuals in 2012 and 12 individuals in 2009. Mainly hunting and habitat loss, but also unsuitable season of reproduction and shortage of forage as minor factors were identified as threats for the local extinction of the Swayne’s Hartebeests. On the other hand, predation, fire, disease and ticks were not considered a cause for the declining trend. Hunting happens mostly out of some kind of revenge since the local community thought that they were pushed out from the land because of the presence of Swayne's Hartebeest in the area. Respondents agreed that the revenge action of the local communities was in response to their unwillingness to be displaced from the park in 1982/3. This conflict situation is resulting from the exclusionary wildlife management policy of the country. We conclude that the human interventions in general and illegal hunting, in particular, pushed the Swayne’s Hartebeest to a point of local extinction. Therefore, we recommend an inclusive wildlife management approach for the continuing existence of the park together with its natural resources so that sustainable use of the resources is in place. Keywords: Hunting • Habitat destruction • Local extinction • Nech Sar National Park • Swayne’s Hartebeest less than 800 [12] or 840 [8] but the recent decline especially in Nech Sar Introduction National Park (NSNP) has been very serious, being only 12 in 2009 [8]. In 1974 Ethiopian Wildlife Conservation Organization translocated Swayne’s Protected Areas (PAs) are designed to protect biodiversity from threats hartebeest from Senekel sanctuary to Awash NP (90) and NSNP (110) [20]. [1]. However, many PAs are only 'paper parks' which are not only highly However, Tischler reported that the translocated Swayne’s Hartebeest had degraded but also a target of continuing exploitation [2]. Conflicts occurring not joined the original population in NSNP and it is not even clear whether between the ethnic groups bordering or living within the parks [3,4] and the the currently surviving population is the original one or the reintroduced one exclusionary PAs policy are among the major causes of the problem [4]. [21]. Ethiopia designated 15% of its land to be PAs [5] whereas the global average is 12% [6]. However, PAs in Ethiopia do not receive adequate protection The NSNP Swayne’s population, since it displays lower genetic variation against human-induced pressures. As a result, serious degradation is and has remained relatively low in the past decades, is vulnerable to threatening much of the home range of wild animals. The distribution and inbreeding depression [16]. It was once suggested that while every effort to population of many mammals are declining [7-12] in response to establish a reserve in-situ should be made, a captive breeding group should anthropocentrically skewed pressures. The endemic and endangered be established in a Zoo in developed nations since the threat of extinction is Swayne’s hartebeest (Alcephalus buselaphus swaynei) is one of them. so great [19]. At the beginning of the 20th century, Swayne’s hartebeest was known to Swayne's hartebeest is an indicator and it was the target species for the be human-induced in Somalia and Ethiopia [13] but now they are restricted to establishment of NSNP [5,22,23]. Although there are studies conducted on the Ethiopian Rift Valley [7] only in Senkele Swayne’s Hartebeest Sanctuary, its population and conservation status few years ago [8,10-12,24] due to high Maze and Nech Sar National Parks [8,12,14-16]. In Awash NP and Yabelo level of human-induced pressures and the quick response of the population sanctuary, they are extinct [12,17] and the species is rated as endangered size of the animal to the pressure, updating the conservation status and [18]. A few years ago, their numbers were still reported to be 700 [18,19]; understanding the people’s knowledge on why this animal is on the verge of local extinction is deemed necessary. Therefore we conducted this research *Corresponding author: Shibru S, Department of Biology, Arba Minch, Arba Minch University, Ethiopia, Tel: +251911637784; E-mail: [email protected] Copyright: © 2020 Shibru S, et al. This is an open-access article distributed under the terms of the creative commons attribution license which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited. Received: 20 January, 2020; Accepted: 04 February, 2020; Published: 11 February, 2020 Shibru S J Biodivers Endanger Species, Volume 8: 1, 2020 to investigate the current population size of Swayne’s Hartebeest and to using one to three scales where one indicates strong reason and three identify the major threats contributing to its local extinction from the savannah indicates the weak reason. plains of NSNP and to recommend better management options for continuing existence of the park and its natural resources for sustainable use. Data analysis For data analysis, we used simple descriptive statistics in an excel Methods spreadsheet. We considered the population size of the animal as the number of individuals counted. Then we divided the population size of the animals by total area of the savannah plains to get the absolute density of the animals. Study area We used mean score values of the scale given by the respondents to We conducted this study in semi-arid savannah plains of NSNP. identify the most serious threat. Similarly, we took mean values (rounded to Established in 1974 and located at 500 km south of Addis Ababa (5° 5’ and the whole number) of the rates of the respondents to identify the most 6° 10’N and 37° 32’ and 37° 48’E), it is one of the oldest parks in Ethiopia. preferred species for illegal hunting. We reported a standard deviation Its altitude ranges from 1180 to 1350masl. The mean annual maximum and together with the averaged values. Identification of the reasons why people minimum temperatures are 30.10℃ and 170℃, respectively and the mean hunt the animals was also accomplished calculating the mean values of the annual temperature is 23.50℃. The mean monthly maximum and minimum respondents’ rate. temperatures are 33.40℃ and 13.60℃ in the months of March and June, respectively. A long rain season is from March to May and a short one is from September to November. The mean annual rainfall is 1041.2 mm. Results The peak means monthly rainfall is in April (180.7 mm) and the minimum in January (35.1 mm) (Arba Minch University Meteorology Station: The population size of Swayne’s Hartebeest 1987-2014). The plains of the park are dominated by soils with high clay content and vertic properties. Vertisols are the most dominant followed by The maximum and the minimum number of Swayne’s Hartebeest we Leptosols and Cambislos. The hills and steep slopes are occupied by counted was 4 in 2012 and 2 in 2014, respectively. Its population size has Leptosols whereas Vertisols dominated on the gentle slopes. The lowest part declined from 130 individuals in 1974 to 2 individuals in 2014, (Figure 1) or a of the plains is occupied by Cambisols [24]. The plains of the park are the density that has decreased from being 0.65 km-2 in 1974 to 0.01 km-2 in dominant feature of the park and the main source of food for grazing animals. 2014. It is the only suitable habitat for Swayne’s hartebeest with an area of about 200 km2 [25]. Threat analysis: Why the population of Swayne’s The park is home for 84 species of wild mammals [22] and is also Hartebeest is declining to the extent of local extinction? inhabited by agro-pastoral and agrarian communities. Its vegetation lies We identified four threats, i.e. two major and two minor, to the decline of within one of the major floristic regions in Africa, the Somali-Masai Regional the population size of the Swayne’s Hartebeest. center of endemism [26] and within one of the IUCN’s global biodiversity hotspots: ‘Horn of Africa’, which is regarded as one of the most degraded Hunting: Hunting was identified by all the respondents as the main threat hotspots in the world, with only about 5% of its original habitat remaining [27].