Ecological Research

, Volume 24, Issue 2, pp 355–370 | Cite as

Identification methods and deterministic factors of owl roadkill hotspot locations in Mediterranean landscapes

  • Luís GomesEmail author
  • Clara Grilo
  • Clara Silva
  • António Mira
Original Article


Road fatalities are among the major causes of mortality for Strigiformes species and may affect the population’s survival. The use of mitigation strategies must be considered to overcome this problem. However, because mitigation along the total length of all roads is not financially feasible, the locations where Strigiformes roadkills are more frequent (i.e., road fatality hotspots) must be identified. In addition to hotspot identification, factors that influence the occurrence of such fatalities should be recognized to allow mitigation measures to be delineated. We used road fatality data collected from 311 km of southern Portugal roads over a 2-year period to compare the performance of five hotspot identification methods: binary logistic regression (BLR), ecological niche factor analysis (ENFA), Kernel density estimation, nearest neighbor hierarchical clustering (NNHC), and Malo’s method. BLR and ENFA modelling were also used for recognizing roadkill deterministic factors. Our results suggest that Malo’s method should be preferred for hotspot identification. The main factors driving owl roadkillings are those associated with good habitat conditions for species occurrence and specific conditions that promote hunting behavior near roads. Based on these factors, several mitigation measures are recommended.


Owls Roadkill Hotspot identification Deterministic factors Kernel Binary logistic regression ENFA 



We thank Rui Lourenço and Frederico Mestre for help solving some issues in this study. This work was supported through a master scholarship from Fundação Eugénio de Almeida to Luis Gomes.


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Copyright information

© The Ecological Society of Japan 2008

Authors and Affiliations

  • Luís Gomes
    • 1
    Email author
  • Clara Grilo
    • 2
  • Clara Silva
    • 1
  • António Mira
    • 1
  1. 1.Conservation Biology Unit, Department of BiologyUniversity of ÉvoraEvoraPortugal
  2. 2.Department of Animal Biology, Faculty of SciencesUniversity of LisboaLisbonPortugal

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