Premium
Abundance Estimation of Diving Animals by the Double‐Platform Line Transect Method
Author(s) -
Okamura Hiroshi,
Kitakado Toshihide,
Hiramatsu Kazuhiko,
Mori Mitsuyo
Publication year - 2003
Publication title -
biometrics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.298
H-Index - 130
eISSN - 1541-0420
pISSN - 0006-341X
DOI - 10.1111/1541-0420.00061
Subject(s) - abundance estimation , estimator , covariate , transect , abundance (ecology) , distance sampling , statistics , sampling (signal processing) , line (geometry) , computer science , data set , set (abstract data type) , econometrics , algorithm , mathematics , ecology , biology , computer vision , geometry , filter (signal processing) , programming language
Summary . In conventional line transect theory, it is assumed that all animals on the line are detected. This article introduces an extended and generalized hazard probability model without the need for such an assumption. The proposed method needs a survey design with independent observers having the same visual region and assumes an explicit distinction of simultaneous and delayed duplicates. It can take account of random heterogeneity caused by surfacing behavior as well as systematic heterogeneity by covariate effects. Furthermore, it can be easily extended to cases in which data from incompletely independent observers are available. The abundance estimate is based on the Horvitz‐Thompson estimator in unequal detectability sampling scheme. Simulation studies suggest that the proposed method has good performance. The method is applied to a real data set on Antarctic minke whales in the illustration.