A Comparison between Nocturnal Aural Counts of Passerines and Radar Reflectivity from a Canadian Weather Surveillance Radar

  title={A Comparison between Nocturnal Aural Counts of Passerines and Radar Reflectivity from a Canadian Weather Surveillance Radar},
  author={F. Gagnon and M. B{\'e}lisle and J. Ibarzabal and P. Vaillancourt and J. Savard},
ABSTRACT. Using a Canadian weather surveillance radar (CWSR), we assessed the relationship between aural passerine counts and radar reflectivity during autumn migration on 16 nights. Reflectivity was positively correlated on all but 1 night with the number of birds detected aurally, but the correlation strength varied between -0.58 and 0.93 among nights (mean ± SD = 0.69 ± 0.42). Using linear mixed-effects models with aural counts nested within nights, we found that the number of birds… Expand
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  • R. Larkin
  • Biology
  • Behavioral Ecology and Sociobiology
  • 2004
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