Behavioral Ecology and Sociobiology

, Volume 29, Issue 3, pp 221–224 | Cite as

Flight speeds observed with radar, a correction: slow “birds” are insects

  • Ronald P. Larkin


Based upon new data and re-analysis of previous data, some results concerning migration of “birds” at night are now attributed to insects. In particular, slowly flying radar targets over land (Larkin and Thompson 1980) and, by analogy, over the ocean (Larkin et al. 1979) are shown to lack wing beat patterns of birds and the appearance of birds when viewed with a radar-controlled high-power telescope and spotlamp. The insect targets overlap with birds in the amount of radar echo returned, are abundant in warmer months, and fly even in March and November in temperate North America. Other previous results are largely substantiated; however, a previous report (Larkin 1980) that migrating birds can detect the wind direction over the ocean is not substantiated.


Wind Direction Migrate Bird Flight Speed Radar Target Wing Beat 
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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • Ronald P. Larkin
    • 1
  1. 1.Illinois Natural History SurveyChampaignUSA

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