Zigzag survey designs in line transect sampling



Zigzag survey lines are frequently used in shipboard and aerial line transect surveys of animal populations. Analysis proceeds assuming that coverage probability through the survey region is uniform. We show that the two types of zigzag design that are in wide use do not generally have this property, and explore the degree of bias in abundance estimates that can be anticipated. We construct a zigzag design for convex survey regions that has even coverage probability with respect to distance along a design axis. We also provide Horvitz-Thompson estimators that allow coverage probability to vary by location through the survey region.

Key Words

Automated design algorithms Coverage probability Sighting surveys Survey design Systematic designs Zigzag designs 


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Copyright information

© International Biometric Society 2004

Authors and Affiliations

  1. 1.Living Landscapes Program, International Conservation ProgramsWildlife Conservation SocietyBronx
  2. 2.Centre for Research into Ecological and Environmental ModellingThe ObservatorySt. AndrewsScotland

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