TRAFFIC RELATED MORTALITY AND THE EFFECTS ON LOCAL POPULATIONS OF BARN OWLS (TYTO ALBA)

This paper presents results of data collected from weekly surveys of traffic induced mortality of barn owls at three sites along two California highways in rural areas from May 25, 1995 to November 26, 1995. For each owl, spot of collection, adjacent habitat and current weather conditions were recorded. Age and sex of the collected owls were determined by differences in molt patterns, plumage and body size. There was a significant difference in the number of collected owls between the three sites. Differences in the adjacent habitat appear to be responsible for the distribution of fatalities among the three sites. Of the 227 owls collected, 61% were juveniles and 39% were adults. There was a significantly skewed sex-ratio: 74% of the collected owls were females. Differences in local population demography and/or vulnerability may result in a greater number of both female and hatching year owls collected. A life history model was constructed in order to assess the impact of traffic related mortality on the growth rate of these populations. Results from the model predict that when about 48% of adult mortality is due to traffic or 27% of the hatching year mortality is due to traffic, the population growth rate drops below one and the population is in decline.

  • Supplemental Notes:
    • Also published by Florida DOT as a paper in FL-ER-58-96, "Trends in Addressing Transportation Related Wildlife Mortality: Proceedings of the Transportation Related Wildlife Mortality Seminar (June 1996).
  • Corporate Authors:

    Florida Department of Transportation

    Haydon Burns Building, 605 Suwanee Street
    Tallahassee, FL  USA  32301

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Authors:
    • Moore, T G
    • Mangel, M
  • Conference:
    • Transportation and Wildlife: Reducing Wildlife Mortality and Improving Wildlife Passageways Across Transportation Corridors
  • Publication Date: 1996-8

Language

  • English

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: p. 125-140

Subject/Index Terms

Filing Info

  • Accession Number: 00745661
  • Record Type: Publication
  • Report/Paper Numbers: FHWA-PD-96-041
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Jan 30 1998 12:00AM