Читать книгу Migration of Birds (1979) - Frederick Charles Lincoln - Страница 6
TECHNIQUES FOR STUDYING MIGRATION
ОглавлениеBefore we discuss the many intricacies of how, when, and where birds migrate, one should have a general idea of how migration data are collected and what methods are currently being used to increase our knowledge. Since this publication first appeared in 1935, many new procedures have been used in the study of bird migration. One of these, radar, has been an invaluable adaptation of a technique developed for a quite different, but related, purpose.