• European house sparrow;
  • human impact on species;
  • passenger pigeon;
  • pest control;
  • superabundance;
  • eighteenth century


The historical superabundance of passenger pigeons in North America and of house sparrows in Central Europe is anthropogenic; that is, the result of human actions, in these cases with unintended consequences. In this article we concentrate on the superabundance of sparrows in the eighteenth and nineteenth centuries and outline the reasons for it. Both the passenger pigeon and the sparrow examples serve as ideal types for misplaced understanding of historical numbers of individuals as indicators of assumed pristine natural situations. Both examples reflect severe human impacts on the metapopulations of the bird species. Historical data on abundance can be misleading when they are used as guides in current conservation efforts. Selections of “right” numbers are arbitrary, because no points of reference exist in natural systems.