Unveiling a mechanism for species decline in fragmented habitats: Fragmentation induced reduction in encounter rates

M. E. Wosniack, M. C. Santos, M. R. Pie, M. C.M. Marques, E. P. Raposo, G. M. Viswanathan, M. G.E. Da Luz*

*Corresponding author for this work

Research output: Contribution to journalArticle (journal)peer-review

16 Citations (Scopus)


Several studies have reported that fragmentation (e.g. of anthropogenic origin) of habitats often leads to a decrease in the number of species in the region. An important mechanism causing this adverse ecological impact is the change in the encounter rates (i.e. the rates at which individuals meet other organisms of the same or different species). Yet, how fragmentation can change encounter rates is poorly understood. To gain insight into the problem, here we ask how landscape fragmentation affects encounter rates when all other relevant variables remain fixed. We present strong numerical evidence that fragmentation decreases search efficiencies thus encounter rates. What is surprising is that it falls even when the global average densities of interacting organisms are held constant. In other words, fragmentation per se can reduce encounter rates. As encounter rates are fundamental for biological interactions, it can explain part of the observed diminishing in animal biodiversity. Neglecting this effect may underestimate the negative outcomes of fragmentation. Partial deforestation and roads that cut through forests, for instance, might be responsible for far greater damage than thought. Preservation policies should take into account this previously overlooked scientific fact.

Original languageEnglish
Article number20130887
JournalJournal of the Royal Society Interface
Issue number91
Publication statusPublished - 6 Feb 2014


  • Encounter rates
  • Foraging
  • Forest fragmentation
  • Lévy processes
  • Population decreasing


Dive into the research topics of 'Unveiling a mechanism for species decline in fragmented habitats: Fragmentation induced reduction in encounter rates'. Together they form a unique fingerprint.

Cite this