The study was conducted in Dhati Welel National Park, Oromia National Regional State, Western Ethiopia. The area is located between 34° 36 0 to 35° 2 30 E longitude and between 9° 6 0 to 9° 30 0 N latitude. The area is located in six districts including Gawo Kebe, Jimma Horro, and Gidami which are found in Kellem Wollega, Zone, and Begi, Kondala, and Babbo Gambel are found in West Wollega Zone. The Park contains the most important wetland ecosystem in the western part of Ethiopia located in the upper basin of the Blue Nile, and approximately covers 1035km²area in size. Figure 1

The most common resources of the park are; the wetland biodiversity including; wetlands dependent and wetlands associated birds, the extraordinary richness of Mega-fauna such as the African Buffalo, and Hippopotamus (Hippopotamus amphibius), and ample fish fauna. Vegetation consists of various floral species including wetland-dependent and wetland-associated plants, and a vegetation type known Sudan-Guinea savanna biome. The study area classified into four habitat types: Wetland, woodland, riverine forest and Savanna grass land. The Park shares the northwestern portion of the southwestern tropical forest part of the country and receives over 1,350mm average annual rainfall. As indicated in Rabira (2019) the area is relatively hot with mean maximum and minimum temperature ranging between 29⁰C and 27⁰C and between 15⁰C and 17⁰C respectively.

The data used for the habitat suitability analysis includes satellite imagery of Landsat 8, Shuttle Radar Topography Mission (SRTM) with 20m resolution (elevation and slope), toposheet (rivers), and settlements. For data preparation, organization, data analysis, and output generation, hardware and software were used. Softwares used for data processing and preparation are ArcGIS 10.5, and ERDAS IMAGINE 2015. To analyze the habitat suitability of Buffaloes in Dhati Welel National Park, the Literature Review and Expert Opinion Habitat Suitability Model were applied. Besides the discussion with Dhati Welel National Park members, published and unpublished materials were reviewed for the convenience of the study. Generally, in the process of habitat suitability analysis for Buffaloes, five factors including LULC, elevation, slope, river, rainfall, and settlement were used.

The study employed LULC interpretation and classification of the study area as one factor. As a result, Landsat 8 OLI images of resolution 30m of the year 2019 were used by downloading from the United States Geological Survey websites. Then image geometric correction and stacking layer of each band were conducted subsequently by using ERDAS IMAGINE 2015 software. Following that, the mosaicking of two scenes was made in order to clip the images of the study area. Supervised classification was performed to classify the LULC of the Dhati Welel National Park. After that Accuracy assessment of the classified image was done by field observation and data was collected using handheld GPS apparatus from sample areas to match the classified image with ground features. Finally, the classified LULC image was crosschecked by overlaying it with Google Earth Image using ERDAS IMAGINE 2015 software. Settlement and river were digitized from the toposheets collected from the Ethiopian Mapping Agency and using ArcGIS 10.5 software proximity computation was performed and analyzed. The Elevation and Slope of the study area were generated from SRTM-30 meter resolution that was downloaded from the United States Geological Survey websites and analyzed using ArcGIS 10.5 software. Figure 2

After each variable converted from vector to raster (rasterization process) continuing through the performing of their analysis, reclassification was performed based on an attribute value that has been specified through ArcGIS software. A pairwise comparison method in the context of the Analytic Hierarchy process was used for the evaluation of the factors. Each assigned weight for the factors was based on a multi-criterion evaluation Analytical Hierarchy Process. The Analytic Hierarchy process uses a nine-point measurement scale i.e. 1 - Equal importance, 3 - Moderate importance, 5 - Strong importance, 7 - Very strong importance, and 9 - Extreme importance. The other values of 2, 4, 6, and 8 constitute intermediate values between two adjacent values.

The Weighted Overlay tool applies one of the most used approaches for overlay analysis to solve multicriteria problems such as suitability models. Each factor in the weighted overlay analysis may not be equal in importance. Weighted overlay analysis was computed using the Influence value assigned to each factor based on their significance in deciding habitat suitability for African Buffaloes.

All factors used in the study were geo-referenced, loaded into the Geodatabase, converted into raster format, and reclassified according to their suitability classes in the ArcGIS environment. After the reclassification process, the suitability classes were identified for each factor. The factor maps were reclassified based on suitability classification standards i.e. highly suitable, suitable, moderately suitable, and unsuitable. In this regard, highly suitable, suitable, and moderately suitable, are areas that in general called habitat-suitable ranges for African Buffaloes. Whereas unsuitable was an area that is not suitable for Buffaloes.

Based on literature reviews and information gathered through interviews on each factor, the following habitat suitability levels were identified for Buffaloes Table 1

LULC of the study area was one of the criteria used to select habitat sites for Buffaloes. The LULC was reclassified according to its suitability for Buffaloes habitats. Depending on the literature reviews and information gathered from the Park, the weight has been assigned for each LULC type. Wetlands are highly suitable and Water bodies are a life requirement for any species of wildlife including Buffaloes. Buffaloes live in swamps, floodplains, mopane grasslands, and the forests of the major mountains of Africa 17179. It prefers a habitat with dense covers such as reeds and thickets 12, and also be found in open woodland. Buffaloes require water daily so they depend on perennial sources of water.

According to Lamsal (2016), the Suitable habitats of Buffaloes are extended to in lower elevations. They are found in dense lowland forests, lowland rainforests, montane forests and grasslands, Acacia grasslands, plains, and semi-arid bushland 22. The highest Buffaloes population densities are found in the wetland part of the Park which is a lower elevation of the study area. Figure 3

According to Pokhrel et al. 27, the suitable habitat for Buffaloes on the slope point of view is along with flat or gently sloping areas. Therefore, Buffaloes prefer a gentle slope rather than a steep slope from the slope gradient perspective. As a result, Slope has been identified as an important factor for Buffaloes. Gentler slopes are more preferable and energy savers during grazing rather than the steepest slope.

Water is one of the life-supporting systems that allows all living things to survive on the surface of the earth (Sinha and Kaushik, 2010). It’s a crucial life requirement for every species and the suitable habitat for Buffaloes is near the rivers. Buffaloes show a preference for riverine habitats, especially in the dry season. They prefer close proximity of less than 1 km to water and are only found within 20 km of water 35. Therefore, suitable habitat for the Buffaloes species is recommended if water is available within a 20km radius. As result, the area found within a 1km distance to the river is termed as a suitable region for Buffalo’s habitat.

Human interference is one of the most problems that disturb the conditions of wildlife including Buffaloes 1034. In and around Dhati Welel National Park, settlements are increased in all areas of the park including the remote and inhospitable areas. As a result, the habitats are more profoundly modified by the human population. Buffaloes are not suitable for living with the closest human settlements. A Settlement with agriculture overwhelmed a large area of woodlands around the wetlands of the park which was the part of former ranges for Buffalo, and therefore, forced Buffaloes to a swampy plain.

The reclassified layers were combined in order to select suitable habitat sites for Buffaloes in the study area. All factors cannot have equal preferences as a result; weighting was used to express the importance or preference of each factor relative to another factor. Accordingly, five factors were standardized and computed by using IDRISI 17 software to produce their weights.

Consequently, the weighted overlay tool in the ArcGIS spatial analyst extension was used to combine all factors according to their rank and weight that has been computed from the pairwise comparison matrix to select the intended outcomes for the suitable habitat of Buffaloes in the study area. Table 2

As it is shown on the above map (Figure 4), the area indicated by dark blue and light blue colors are suitable and highly suitable for the habitats of Buffaloes. These areas are found around the central and wetland-dominated portion of the National Park. The remaining area shown on the map in red and black color represents the area moderately suitable and unsuitable for Buffaloes habitat respectively. From the total area of the park, 35.4% (362.7km²), and 44.1% (452.8km²) found as highly suitable and suitable for Buffaloes habitats respectively. These areas fulfill the optimal requirement for habitats based on the factors analyzed in the study. The remaining 20.4% (209.3km²), and 0.1% (1.1km²) of the study area were found as moderately suitable and unsuitable for the habitat of Buffaloes respectively. These were areas occupied by anthropogenic activities and known by habitat fragmentation in the park.