D2 Plumage Analysis

Title

D2 describes methods for quantifying plumage condition as a physical variable that affects wing aerodynamics. The central difficulty of this diagnosis is that the damage to the plumage is heterogeneousit can affect the microstructure of the barbules without the wing appearing visually deterioratedand that its aerodynamic effects (increase in C_D, loss of C_L_max) are not linear or uniform. D2 defines a quantification protocol using multispectral photography and digital image analysis that produces the I_deg index, usable directly in the equations of A2. The method also includes the measurement of slots between primary rémiges (whose loss increases the induced drag) and the estimation of surface roughness by optical profilometry. UV reflectance is included as an indicator of general plumage health in species with tetrachromatic vision, correlated with parasitism and nutritional stress.

ID:4222