Novel genes continue to enhance population growth in adders (Vipera berus)

Research output: Contribution to journalArticle


In 1999, we published a report on how an introduction of 20 males into a severely inbred and isolated population of adders (Vipera berus) halted its decline towards extinction, induced a profound change in population genetic variability, resulted in a dramatic increase in offspring viability and thus in a rapid increase in numbers. Since the publication of our paper we have received numerous inquiries as to whether we have continued to monitor this population, as this is the case we herein present population demographic data gathered between 1981 and 2003. The population has continued to increase in numbers and in 2003, we collected 39 adult male adders, more than at any time over the 23-year study. Our continued work, hence, lends strong support to the importance of novel genes in enhancing the viability of inbred populations and supports the importance of preserving genetic variability in order to maintain viable wild populations.


  • Thomas Madsen
  • Beata Ujvari
  • M Olsson
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ecology
Original languageEnglish
Pages (from-to)145-147
JournalBiological Conservation
Issue number1
Publication statusPublished - 2004
Publication categoryResearch