Biodiversity and Conservation

, Volume 27, Issue 6, pp 1387–1402 | Cite as

Impact of habitat fragmentation on the spatial structure of the Eastern Arc forests in East Africa: implications for biodiversity conservation

  • William D. NewmarkEmail author
  • Phoebe B. McNeally
Original Paper
Part of the following topical collections:
  1. Forest and plantation biodiversity


The Eastern Arc Mountains in Tanzania and Kenya are one of 35 global biodiversity hotspots. The Eastern Arc forests are, as are many other tropical biodiversity hotspots, highly fragmented. Understanding the impact of habitat fragmentation (i.e., habitat loss and subdivision) on the spatial structure of the Eastern Arc forests is important because forest spatial structure highly influences species richness, persistence, and extinction debt. Here we examine the impact of habitat fragmentation on the spatial structure of the Eastern Arc forests at a patch scale using very high resolution aerial imagery having a spatial resolution of 0.5–1.5 m. Forest area across the 13 Eastern Arc Mountains is 405,852 ha and is distributed into 311 fragments ≥ 10 ha in size with a median fragment size of 84 ha. The 18 largest forest fragments in the Eastern Arc Mountains contain greater than three-quarters of total forest area. Average fragment isolation, as assessed by median distance to nearest fragment and median distance to the nearest larger fragment, is 867 and 1533 m, respectively. Of total forest area, 14% is < 100 m from the forest edge and 33% is < 300 m from the forest edge. Establishing forested linkages among the largest and closest forest fragments through forest regeneration and protection of secondary regenerating forest as well as providing protected area status to the remaining non-protected forest including unprotected smaller forest fragments are important to enhancing the long-term persistence of many plant and animal species here.


Fragment size and number Fragment isolation Edge area Forest cover Kenya Tanzania 



We thank the Danish International Development Agency, Field Museum of Natural History, Chicago Zoological Society, Sophie Danforth Conservation Fund, National Geographic Society (#524-94, #977815), Earthwatch Institute, John D. and Catherine T. MacArthur Foundation, Critical Ecosystem Partnership Fund, World Wide Fund for Nature, and Earth Point Corporation for support, and the Tanzania Wildlife Research Institute and Tanzania Commission for Science and Technology for permission to conduct this study.


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© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Natural History Museum of UtahUniversity of UtahSalt Lake CityUSA
  2. 2.Department of GeographyUniversity of UtahSalt Lake CityUSA

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