The ecology and management of elephants (loxodonta africana matschie) in the bia – goaso forest enclave of western ghana

Elephants are important mega fauna whose role in an ecosystem could ensure the health and survival of diverse species. However, drastic declines in their numbers since the 19th Century in Africa in general and West Africa in particular has necessitated the need to understand their ecology in the local context to help improve their survival. This study was therefore conducted in the Bia-Goaso forest enclave in Ghana to contribute to the achievement of the objectives of the Elephant Conservation Strategy of Ghana (2000) and the “Action plan for the Management of the Transfrontier Elephant Conservation Corridor of Bia-Goaso-Djambarakrou,” which contain activities geared towards ensuring the survival of forest elephants in Ghana and West Africa respectively. In February 2004, a dry season survey on elephants and an investigation into the different levels of human and ecological variables that affect their abundance and distribution was conducted in an extensive network of eleven forest reserves and two wildlife reserves in the Bia–Goaso enclave of western Ghana. These activities were repeated twice, first in the rainy season of 2007 and the following dry season which started in 2007 and ended in 2008 mainly to understand seasonal effects in distribution of elephants in the area. During this period, the most up-to-date method for surveying forest elephants, the retrospective method was employed. A desk-top exercise was then undertaken not only to prove the importance or otherwise of the elephant populations in the study area in comparison with other elephant populations in West Africa but also to determine factors that govern their abundance. A preliminary investigation into the feasibility of creating corridors between reserves in the study area and neighbouring Ivory Coast was initiated in May 2004. As part of this, the movements of elephants from Ghana into Ivory Coast along the Bia river was monitored every quarter between August 2005 and December 2006, as well as an investigation into the rate of forest degradation. The nature and extent of human – elephant conflicts in the Bia Conservation Area was also studied through administration of questionnaires using interviews and field measurements. One hundred and thirty (130) transects were systematically distributed in three strata (high, medium and low density) based on dung pile density estimates in an initial reconnaissance. Two models (rainfall and steady state assumption models) were used to estimate elephant dung pile density and numbers in the study area. However, the rainfall model is preferred since it iii makes no assumption about the state of the forest. Two major elephant populations were observed to be residing in the study area, with the possibility of a tiny third population of less than 10 elephants (in the Bia North FR). In the 2004 survey, a mean population estimate of 115 (CL: 90 - 148) elephants was obtained for the Bia Resource Reserve. The eastern portion of the Mpameso Forest Reserve (medium density stratum) had an estimate of 57 (CL: 33 - 100) elephants. Elephant numbers could not be estimated for the rest of the reserves (low-density stratum) because of inadequate number of dung piles on transects. In the 2007/8 survey, estimates of 133 (CL: 104 - 162) elephants and 137 elephants (CL: 98 - 170) elephants were obtained for Bia CA during the dry and wet season surveys respectively. While for the Mpameso elephant range, estimates of 83 (CL: 41 - 125) elephants and 90 (CL: 49 - 131) elephants were obtained in the dry and wet seasons respectively. Merged estimates for both seasons were 135 (CL: 114 - 156) elephants for Bia and 87 (CL: 58 - 116) elephants for Mpameso. Altogether, a total population of 172 (CL: 123-264) elephants were estimated to be occurring in the entire study area. Elephants were found to be clumped more to the southeast of BRR, the eastern part of Mpameso and the Bia Shelterbelt FR. Elephants were found to be more widely spread out in the wet season than in the dry season within BCA. Analysis of dung pile distribution in relation with human and ecological variables in both the 2004 and 2007/8 studies showed that within the reserves, water availability explained a high proportion (ca. 90%) of the variance in elephant density, with elephants being clumped around watering points created as a result of logging. Additionally, in 2004, distance to the Bia River was inversely correlated to the number of dung piles seen per km in the Mpameso Forest Reserve. Illegal activities (such as snaring and snail picking), however, did not affect elephant abundance but rather had a negative correlation with watering points, that is, they were undertaken away from these watering points. This suggests that poachers were avoiding areas of high water availability, possibly because of high elephant activity around those areas. Outside reserves, the distance to major towns and roads accounted largely for variances in elephant density in 2004. In 2007/8 on the other hand, logging roads and availability of raphia also entered the model as significant variables, though they did not add much power to the models. By all standards, the Bia population on its own is a very important one in the sub-region. The Goaso population is smaller. However, the security of its range, and the possibility of linking it with others makes it also even iv more important for the overall conservation of forest elephants in West Africa. It was established during the study that elephant abundance in West Africa depends on the size of a population‟s range, to whether the range is protected, its geology and the quality of governance in the country where it occurs. Elephant crop damage is a serious problem in the area, especially to cluster of farms that border the southern portions of the Bia Resource Reserve, resulting in conflicts between farmers and nature conservation. Food crops such as plantain, cassava, cocoa and maize suffered severest damage. These are most preferred by the elephants when in the matured state and the quality is excellent. For each community, that suffered crop-raiding, the extent of crop-raiding depended not only on the area of land under cultivation but also the mean distance of farms from the reserve boundary, as well as the number of different crops planted on the farm. Interviews conducted in 2004 indicated that most migrant farmers do not see any advantage in preserving elephants and would do little to conserve them. While they were not willing to sacrifice part of their already overburdened farmlands for establishing elephant corridors, they also feared a possible increase in human-elephant conflicts in the future. However, most villages adjacent to streams/rivers showed a strong interest in restoring the riparian forest since they faced water and fish shortages in the dry season. More lately, there have been several forest restorative activities going on in the study area in the hope of returning wildlife into communal lands. Hence, there has been a generally increasing level of awareness concerning the conservation and protection of lands to serve as corridors. Of six potential corridors considered, one along the Bia river linking the Goaso population to those in Ivory Coast and from Bia Resource Reserve to Krokosue Hills Forest Reserve have the greatest potential in the short to medium term, and it is also likely that with a high level of interventions, two others could be achieved over the long term. A more detailed spatial analysis in combination with ground truthing is required before a conclusive decision on viable corridors can be made. Also a more participatory information gathering strategy (such as Timelines, H-Diagram) for soliciting community opinions on corridors have been suggested to complement the use of questionnaires. Recommendations also include a detailed study of elephant movements in the Ivorian side of the corridor.

Source: KNUST