Coral Reefs

, Volume 2, Issue 1, pp 37–42 | Cite as

Correction for bias in visual transect censuses of coral reef fishes

  • P. F. Sale
  • B. J. Sharp


Transect techniques for censusing reef fishes, and the sources of bias inherent in them are considered. A technique, derived from aeraly survey methods, is demonstrated to correct a bias in density estimates due to the width of the transect being censused. This bias is sufficient on a transect 1 m wide to underestimate density by 11.1–26.7% for five species or species groups examined. The bias is still greater on wider transects. Because this bias varies in degree among species, comparisons among species should not be made using uncorrected transect data. Comments are made on other probable sources of bias in transect data, and on ways of minimising bias when making visual transect censuses.


Coral Reef Density Estimate Species Group Sedimentology Reef Fish 
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Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • P. F. Sale
    • 1
  • B. J. Sharp
    • 1
  1. 1.School of Biological SciencesUniversity of SydneySydneyAustralia

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