Variation in mammal diversity and habitat affect heterogeneity and processes of a granite catena

Beanelri B Janecke,Jeremy G Bolton

doi:10.4102/koedoe.v62i2.1592

Abstract

A higher variety of habitats normally result in higher diversity of species. The granite catenas near Skukuza, Kruger National Park (KNP), consist of different soil types along the hillslope, creating different habitats. Objectives were to determine the mammal species present on a catena and surrounding areas; to indicate their main period of activity; and to indicate human visibility in each catenal zone to explain landscape of fear principles. Camera trap surveys were conducted for short periods and repeated over three years. In total, 31 mammal species were observed on the catena, and its nearest waterholes. Small to mega-sized mammals were present, but some species were only observed during one survey period. Small changes were noticed in activity periods between survey periods, probably due to the drought. A severe drought changed vegetation structure and visibility, but the study area appeared to act as a drought forage refuge. The lowest visibility was found at the sodic patch upper-midslope ecotone, and shrub veld. This can possibly explain the lower number of mammal observations in these areas. Different habitats and habitat features were described which can affect the presence of mammals, i.e. the mud wallows that were created and maintained by the mammals. Future studies can focus on the impact of seasonal changes in mammal presence and on mammal diversity during a normal rainfall year. Conservation implications: To understand the mechanisms of herbivores as ecosystem drivers, aspects such as vegetation, soil and mammals should be combined. Better understanding of mammals, their habitats and associated processes can lead to better conservation actions.

Highlights

Acceptable habitat conditions are one of the most important requirements for successful maintenance of animal populations
A snapshot approach was followed to give an idea of the mammal species that frequent the study area – in other words, the cameras were only left in the veld for short periods during each survey period
There is nothing obvious that can prohibit movement of animals through the study area, and considering the park has a large surface area catering for various species, the possibility is high that some mammal species, especially the smaller mammals, were not listed

Summary

Introduction

Acceptable habitat conditions are one of the most important requirements for successful maintenance of animal populations. Resources in the habitat are exploited differently in order for animals to fulfil their requirements for survival, reproduction and growth (Owen-Smith 2002). Habitat implies more than vegetation or vegetation structure; it is the sum of the specific resources that are needed by organisms. Habitat is any area where an animal has the necessary resources that allow it to survive, including migration paths, dispersal corridors and areas occupied during breeding times (Hall et al 1997; Krausman & Morrison 2016). Habitat selection refers to a process where an animal selects a specific set of environmental factors that can provide all the essential resources it needs to survive and reproduce (Bonyongo 2005; Johnson 1980; Krausman & Morrison 2016). Other features that are included when an animal selects a habitat are the vegetation structure of the area, certain geomorphological features, topography, seasonal availability of resources, distance from

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Discussion

Conclusion