Population Ecology

, Volume 56, Issue 2, pp 341–348 | Cite as

Are habitat loss, predation risk and climate related to the drastic decline in a Siberian flying squirrel population? A 15-year study

  • Jane Koskimäki
  • Otso Huitu
  • Janne S. Kotiaho
  • Satu Lampila
  • Antero Mäkelä
  • Risto Sulkava
  • Mikko Mönkkönen
Original article


To devise effective conservation actions, it is important to know which factors are associated with the population parameters of a declining population. Using mark–recapture methods, we estimated the annual population size, growth rate and survival probability of an ear-tagged flying squirrel population over a 15-year period in a 4,500 ha study area in western Finland. The species is considered vulnerable, but detailed knowledge concerning population sizes or trends is lacking. The population parameters and changes therein were regressed against habitat availability, an indicator of predation pressure, and mean winter temperature (an indicator of climate change), to reveal potential reasons for trends in the population. The best-fit models suggested the annual growth rate to be below one, and on average it was 0.93 (±0.06; SE) across the 15-year period. The survival probability was about 0.22 (±0.03) for juveniles and 0.50 (±0.03) for adults. The population size of adult flying squirrels decreased from 65 (±11) individuals in 1995 to 29 (±6) individuals in 2009. The number of flying squirrels was associated with the amount of available habitat, but the decline in population size was more rapid than the loss of habitat area. If the current decreasing trend in habitat availability continues, the population might become extinct by the year 2020. To halt the population decline, it is necessary to refrain from clear-cutting mature spruce stands until new suitable habitats develop from the maturation of younger forests.


Alternative prey hypothesis Landscape change Mark–recapture analysis Population regulation 



This manuscript was reviewed at Peerage of Science. We are grateful to two anonymous peers at the Peerage of Science and three reviewers for their useful comments. The study was financially supported by the South Ostrobothnia Regional fund of the Finnish Cultural Foundation (to JK), the Academy of Finland (Grant No. 133495 to OH; Grant No. 7115560 to MM) and by Maj and the Tor Nessling Foundation (Project# 2012580 to MM).


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Copyright information

© The Society of Population Ecology and Springer Japan 2013

Authors and Affiliations

  • Jane Koskimäki
    • 1
  • Otso Huitu
    • 2
  • Janne S. Kotiaho
    • 1
  • Satu Lampila
    • 3
  • Antero Mäkelä
    • 4
  • Risto Sulkava
    • 5
  • Mikko Mönkkönen
    • 1
  1. 1.Department of Biological and Environmental SciencesUniversity of JyväskyläJyväskyläFinland
  2. 2.Suonenjoki UnitFinnish Forest Research InstituteSuonenjokiFinland
  3. 3.Department of BiologyUniversity of OuluOuluFinland
  4. 4.Linnantie 10SulkavankyläFinland
  5. 5.Finnish Association for Nature ConservationHelsinkiFinland

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