A NEW MULTI-CATEGORY CLASSIFICATION OF SUBCUTANEOUS FAT DEPOSITS OF SONGBIRDS

A new fat scoring technique for small birds is introduced using 31 classes (nine main classes with up to four subclasses each; Fig. 1). In contrast to many other methods, fat score and respective fat load (as determined by the Soxhlet method) correlate very well. Furthermore, variability in the calculated regression lines for nine different species is low. This effective new method can easily be learned by handling approximately 100 individual birds and substantially improves precision of studies on fat-deposition in migratory birds.