A new approach to recording plumage deterioration

1. Recording methods for the scoring of plumage wear are reviewed. 2. A new technique, distinguishing between feather tracts, the surface to which damage occurs and the degree of degradation to the feathers themselves is elaborated: a 5 step scale for degradation is applied to all appropriate fractions of 6 feather regions. After correcting for the normal feather weight in the respective areas, all 6 area values are summed to constitute an overall index of body plumage wear (IBPW).