Habitat Choices of Nubian Ibex (Capra Nubiana) Evaluated with A habitat Suitability Modeling and Isodar Analysis

Abstract

The value of a habitat for a forager may be affected by habitat characteristics related to food availability, energetic costs of foraging, predation costs, and the foraging opportunities available in other habitats. Nubian ibex (Capra nubiana) are stout, sure-footed social wild goats that inhabit arid landscapes with steep terrain. We investigated their habitat selection behavior using indicators to (1) develop a habitat suitability index (HSI) model that would account for the variation in the activity densities of Nubian ibex across habitat types and seasons, (2) apply the isodar technique to look for density-dependent habitat selection behavior in Nubian ibex, and (3) investigate the proximate environmental factors that correlate to relative activity densities of Nubian ibex. We determined relative densities of the ibex by recording sightings of animals along standard walking transects. We incorporated the habitat variables that had greatest influence on the densities of Nubian ibex into habitat suitability index models for both spring and summer seasons.The HSI models revealed that Nubian ibex most preferred open cliff face habitat offering safety during the spring season, but their habitat preference shifted towards an area with watered gardens ("grave area habitat") during the summer season. Significant isodars were only obtained for the summer season comparisons between grave area versus cliff face, and between grave area versus plateau habitats. The slopes of the isodars suggest that the grave area habitat is 10.5 and 7.6 times more productive than the plateau and the cliff face habitats, respectively. Our results suggest that the relative abundances and habitat preferences of Nubian ibex varied with the seasonal availability of habitat resources, extent of predation risks, and human nuisance disturbances across the landscape. We recommend that wildlife managers dealing with the conservation and protection of the endangered Nubian ibex should focus on the various ecological and anthropogenic factors governing the habitat selection and preferences.

A GIS‒based habitat suitability model for the mountain nyala tragelaphus buxtoni in the southeastern highlands of Ethiopia and its implication for conservation

“…the mountain nyala) with the influential habitat variables, one could develop a statistical habitat suitability model at a small spatial scale that can complement the GIS-based habitat suitability model. 9,13,17,32 Factors, such as livestock grazing, deforestation, and illegal hunting pressures could not be included into the present model. This is because they are dispersed throughout the whole ranges of the mountain nyala in Ethiopia.…”

“…3,10,13,25 However, by using the behavioral approach based on activity densities; those factors could be successfully included into the statistical habitat suitability model at small spatial scale. 13,17,32 This is because the suitable habitats can be directly inferred from the behavioral responses (i.e. activity densities, time budgets, foraging behaviors, etc.)…”

Contribution of the Guassa Community Eco-Lodge to the Conservation of Wild Mammals, Birds and Woody Plants in Menz-Gera Midir District, North Shewa Administrative Zone, Ethiopia

“…Accordingly, a total of six transects were aligned, i.e, three transects within the EHH and other three transects within the FGH. Along each transect, the viewable area of each habitat patch was quantified by walking perpendicularly from a given line transect until the unevenness of the topography or the thickness of the vegetation cover no longer allowed viewing that transect [9,10]. The GPS locations on both sides of all the viewable parts of each habitat type were then taken.…”

“…Unlike wild mammals and woody species richness, the species richness of birds was higher in the EHH than in the FGH. Some of the possible reasons for unequal distribution of the bird species in the two adjacent habitats could be attributed by the difference in habitat resource gradient and densities [9,10,20] and the presence of human-and livestock-induced disturbances [3,4,21,22]. In addition, the behavior of some bird species (e.g.…”

Patch use and site selection by a rock hyrax (Procavia capensis) in a human-dominated landscape in the West Bank of Palestine

“…Examples of behavioral indictors include Habitat Suitability Index (HSI) models based on activity densities and relevant environmental and habitat variables (e.g. Tadesse and Kotler 2010), isodars from density-dependent habitat selection theory (e.g. Morris 1987), and giving-up densities from optimal patch use theory (Brown 1988(Brown , 1992.…”