Population Ecology

, Volume 59, Issue 2, pp 157–168 | Cite as

Movements and source–sink dynamics of a Masai giraffe metapopulation

  • Derek E. LeeEmail author
  • Douglas T. Bolger
Original article


Spatial variation in habitat quality and anthropogenic factors, as well as social structure, can lead to spatially structured populations of animals. Demographic approaches can be used to improve our understanding of the dynamics of spatially structured populations and help identify subpopulations critical for the long-term persistence of regional metapopulations. We provide a regional metapopulation analysis to inform conservation management for Masai giraffes (Giraffa camelopardalis tippelskirchi) in five subpopulations defined by land management designations. We used data from an individual-based mark–recapture study to estimate subpopulation sizes, subpopulation growth rates, and movement probabilities among subpopulations. We assessed the source–sink structure of the study population by calculating source–sink statistics, and we created a female-based matrix metapopulation model composed of all subpopulations to examine how variation in demographic components of survival, reproduction, and movement affected metapopulation growth rate. Movement data indicated no subpopulation was completely isolated, but movement probabilities varied among subpopulations. Source–sink statistics and net flow of individuals indicated three subpopulations were sources, while two subpopulations were sinks. We found areas with higher wildlife protection efforts and fewer anthropogenic impacts were sources, and less-protected areas were identified as sinks. Our results highlight the importance of identifying source–sink dynamics among subpopulations for effective conservation planning and emphasize how protected areas can play an important role in sustaining metapopulations.


Matrix population model Metapopulation Population dynamics Rescue effect Source–sink 



This research was carried out with permission from the Tanzania Commission for Science and Technology (COSTECH), Tanzania National Parks (TANAPA), the Tanzania Wildlife Research Institute (TAWIRI), African Wildlife Foundation, Manyara Ranch Conservancy, and the villages of Selela, Lolkisale, and Emboret, under COSTECH permits 2011-106-NA-90-172, 2012-175-ER-90-172, and 2013-103-ER-90-172. I am extremely grateful to these organizations for the opportunity to conduct this research, especially J. Keyyu, V. Kakenge, A. Mwakatobe, and K. Oola at TAWIRI; F. Olekashe at Manyara Ranch Conservancy, J. Salehe at African Wildlife Foundation, and I.A. Lejora, D. Njau, S. Quolli from TANAPA. M. Bond assisted with data collection and processing. Financial support for this work was provided by Dartmouth College Graduate Studies, Fulbright U.S. Scholar Program, Sacramento Zoo, Safari West, Columbus Zoo, Cincinnati Zoo, Dartmouth College Cramer Fund, and the Explorer’s Club.

Supplementary material

10144_2017_580_MOESM1_ESM.pdf (635 kb)
Supplementary material 1 (PDF 635 KB)


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Copyright information

© The Society of Population Ecology and Springer Japan 2017

Authors and Affiliations

  1. 1.Department of Biological SciencesDartmouth CollegeHanoverUSA
  2. 2.Department of Environmental StudiesDartmouth CollegeHanoverUSA
  3. 3.Wild Nature InstituteConcordUSA

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