Vanishing Wildlife Corridors and Options for Restoration: A Case Study from Tanzania

Abstract

Conserving wildlife corridors is increasingly important for maintaining ecological and genetic connectivity in times of unprecedented habitat fragmentation. Documenting connectivity loss, assessing root causes, and exploring restoration options are therefore priority conservation goals. A 2009 nationwide assessment in Tanzania documented 31 major remaining corridors, the majority of which were described as threatened. The corridor between the Udzungwa Mountains and the Selous Game Reserve in south-central Tanzania, a major link between western and southern wildlife communities, especially for the African elephant Loxodonta africana, provides an illuminating case study. A preliminary assessment in 2005 found that connectivity was barely persisting via two remaining routes. Here we present assessments of these two corridors conducted from 2007-2010, using a combination of dung surveys, habitat mapping and questionnaires. We found that both corridor routes have become closed over the last five years. Increased farming and livestock keeping, associated with both local immigration and population growth, were the main reasons for corridor blockage. However, continued attempts by elephants to cross by both routes suggest that connectivity can be restored. This entails a process of harmonizing differing land owners and uses towards a common goal. We provide recommendations for restoring lost connectivity and discuss the prospects for preventing further loss of corridors across the country.

Assessing Habitat Quality of Forest-Corridors through NDVI Analysis in Dry Tropical Forests of South India: Implications for Conservation

“…Apart from that, large-scale farming and infrastructure development also increased over the years. These factors might have reduced the extent and the quality of wildlife habitat [62,63]. Similar results were found in the "composite threat index" map ( Figure 7b) developed by Barve et al (2005) for BRT [11].…”

Indicators for Assessing Habitat Values and Pressures for Protected Areas—An Integrated Habitat and Land Cover Change Approach for the Udzungwa Mountains National Park in Tanzania

“…In total around 1091 km 2 of natural vegetation was converted to agriculture and other anthropogenic land uses in the 20 km buffer zone over the analyzed 20 year time frame, removing a large proportion of the natural vegetation in the above mentioned corridors. In fact, previous studies demonstrate that the Udzungwa-Selous corridors are currently closed-in particular for elephants [57]. The HFT 3 map presented in Figure 7 confirms this, clearly showing a similar habitat towards the Selous Game Reserve which however is not connected anymore to the UMNP due to the above illustrated land cover changes.…”

“…The HFT 3 map presented in Figure 7 confirms this, clearly showing a similar habitat towards the Selous Game Reserve which however is not connected anymore to the UMNP due to the above illustrated land cover changes. Jones, et al (2012) noted that increased farming and livestock keeping, associated with both local immigration and population growth, were the main reasons for these corridor blockage and closure. However, the authors highlight also the fact that continued attempts by elephants to cross the blocked routes suggest that connectivity can be restored.…”

Sustainability in the Food-Water-Ecosystem Nexus: The Role of Land Use and Land Cover Change for Water Resources and Ecosystems in the Kilombero Wetland, Tanzania

“…Hence, fire prone areas can be seen from the satellite images even though they are not classified here. Jones et al (2012) [87] reported the recent loss of functionality of two wildlife corridors; Nyanganje and Ruipa. They connected the Selous Game Reserve to the South-East with the Udzungwa Mountains National Park to the North-West.…”